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TABLE OF CONTENTS

Section 1 2 3 4 5 6 7 8 9 Page The Company ......................................................................... 1 Snapshot of APTECH .............................................................. 3 Project Experience .................................................................. 11 Staff Qualifications.................................................................. 17 References .............................................................................. 25 Client List ............................................................................... 31 Case Summaries -- General ................................................... 35 Case Summaries -- Fires & Explosions .................................. 45 Case Summaries -- Construction............................................ 59

ON THE COVER:

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1. Construction Support Services 2. Analysis of Chemical Plant Explosion 3. Microscopic View of Corrosion in Cast Iron Valve 4. Steam Piping Life Assessment 5. Nondestructive Examination

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6. Oil Pipeline/Bridge Collapse 7. Turbine Blade Failure 8. Refinery Operations Risk Assessment 9. Bridge Cracking Evaluation 10. Cavitation Corrosion in Molding Machine

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Section 1

THE COMPANY

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PTECH Engineering Services, Inc., is an internationally recognized engineering consulting firm dedicated to the support of industrial systems, and to the prediction, prevention, investigation, and analysis of failures. A significant portion of our consulting work is in the insurance and legal areas, providing engineering analysis of major losses. We rely on expertise in the following technical disciplines: Mechanical, chemical, civil, and electrical engineering Metallurgical and materials engineering Thermosciences and fire and explosion origin/cause analysis Engineering mechanics and welding technology Petrochemical, power, process, production, and marine engineering Risk and economic analysis

Since our founding in 1979, we have performed more than 4,000 engineering projects throughout the United States and abroad, primarily in the following industries: Fossil and nuclear power generation Process, chemical, and petrochemical Oil and gas pipelines Construction and environment Commercial and residential Legal and insurance Transportation and marine Aerospace and aviation The engineering services we provide to industry are focused on assuring the continued efficiency and cost-effective performance of process systems. We begin by obtaining a clear understanding of the client's needs. After appropriate analyses, we are then able to provide reliable engineering recommendations upon which informed management decisions involving maintenance, component replacement, and projected life can be based. But, what happens when things go wrong? Failures of systems and components often result in costly downtime and cause pollution, damage, or injury. At such critical times, APTECH's skillful accident investigation and reconstruction will uncover the circumstances leading to the calamity. Failure analysis techniques are used to identify the immediate and root cause of failure. Investigations

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typically focus on operating parameters, system and component design, and the equipment's condition and maintenance history. In addition, we can analyze the consequences of system failure, helping to evaluate the cost and effectiveness of alternative solutions. Accidents and failures usually result in insurance claims and often lead to litigation. Our diverse engineering expertise, as well as our familiarity with the claims and litigation process, enable us to clarify the complex technical issues involved. Our professional services are characterized by relevant expertise, timely response, and open communication. APTECH is ideally positioned to be a part of your claims/litigation team. Our highly trained engineering staff, project experience, and technology base provide the capabilities and credentials to support insurance/legal activities in the industries we serve. Operating from our headquarters in Sunnyvale, California (San Francisco Bay Area), and with strategically located offices in the eastern and central United States, we can be responsive to the needs of our clients. If APTECH may be of assistance, please contact our nearest office.

Corporate Headquarters

1253 Reamwood Avenue Sunnyvale, California 94089 Toll Free: 800.477.2228 Phone: 408.745.7000 Fax: 408.734.0445 Contact: Dr. Kimble J. Clark (x3032) or Dr. Geoffrey R. Egan (x3024) Website: www.aptecheng.com E-Mail: [email protected]

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Section 2

SNAPSHOT OF APTECH

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his section presents a quick overview of APTECH Engineering Services, Inc. The following topics are covered: What is APTECH? Services Offered Industries Engineering Specialties Resources U.S. Offices and Projects International Representatives and Projects How Our Services Are Applied The APTECH Approach What APTECH Can Do For You Characteristics of an APTECH Expert Root Causes of Accidents and Failures

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What is APTECH?

Engineering services firm Focused on industrial equipment and systems 50 full-time employees Headquarters in California Offices in Connecticut, Florida, Maryland, Missouri, North Carolina, Ohio, and Texas

Services Offered

Prior to Accident, Loss, or Failure:

Condition Assessment Life Cycle Management Reliability Forecasting and Improvement

After Accident, Loss, or Failure:

Failure Analysis Field Inspection and Accident Reconstruction Run/Repair/Replace Cost Estimation Claims and Litigation Support

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Industries

Power Generation

Chemical and Petrochemical

Construction and Environment

Marine and Transportation

Aerospace and Aviation

Insurance and Legal

Engineering Specialties

Metallurgical and Corrosion

Chemical Mechanical Civil and Environmental

Electrical

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Resources

Professional Staff

Lab and Test Facilities

Engineering Analysis Tools

Field Services Personnel

Information and Research Library

State-of-the-Art Presentations

Failure Databases

Consultants Network

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U.S. Offices and Projects

Offices Projects

International Representatives and Projects

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How Our Services are Applied

25%

Claims & Litigation Support

Commercial Engineering Services

75%

The APTECH Approach

Clear communication Team approach · Knowledge of materials, process, and design · Specific equipment experience and in-depth technology expertise Fast response · Gather all relevant data · Inspect site ASAP · Preserve evidence Follow-up analyses and tests State-of-the-art presentations · Graphics and storyboards · Laserdisc and barcode reader · Computer animation

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What APTECH Can Do For You

Inspect and document site Identify and preserve evidence Determine root cause of failure Estimate repair cost Get the equipment back on line Assist subrogation efforts Support litigation

Characteristics of an APTECH Expert

Relevant expertise and credentials Practicing engineer -- not "professional expert" Knowledge of legal/insurance business Good listener and communicator Responsive to client requests Focused and practical Networking within their field

Root Cause of Accidents and Failure

Design Defect

Human Error

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Material or Manufacturing Defects

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Section 3

PROJECT EXPERIENCE

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PTECH stands ready to provide engineering analysis in property, casualty, and marine and aviation losses, as well as risk assessment and prevention. The breadth of experience we bring to the client's service is illustrated by this partial list of projects we have completed in diverse industries. Additional details, including reports and project summaries, are available upon request.

Boilers and Machinery

Catastrophic failure of high energy steam piping seam welds Header and steam drum cracking Plant performance and design disputes Boiler explosions and implosions Fuel burning and handling equipment failures, fires, and explosions Effects of cycling and re-rating on component lifetimes Power plant economic analysis Steam and combustion turbine blade, rotor, disc, and shell failures Generator retaining ring stress corrosion cracking Diesel engine cam shaft and valve wear Cogeneration gas turbine blade failures Valve malfunction and failures Off-normal water chemistry effects Superheater steam flow redistribution Remaining useful life (RUL®) analysis Pulverizer, fan, pump, air heater, and heat exchanger investigations Combustion tuning NOx compliance evaluation Stack emissions reduction

Process, Petrochemical & Refining Industries

Pressure vessel and piping failures Rocket fuel oxidizer (ammonium perchlorate) plant explosion Urea autoclave explosion Dust explosions and fires Oil production fires (pump tank; drill rig) Hydrogen gas valve fire Refinery piping elbow erosion, failure, and fire Offshore platform damage and collapse Pressure vessel analysis for hydrogen damage Turbine failure and fire 11

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Smelting furnace failure Laser cutting machine malfunction Molding equipment failure Poultry chilling equipment wear and tear Poultry feed mill malfunction Compressed natural gas (CNG) storage, transport, and delivery Steel mill coke oven gas explosion Gas furnace explosion Annealing tank (molten salt) explosion Food processing equipment failures Industrial refrigeration system performance assessment Life extension of an LNG/LPG plant Compliance with OSHA 1910

Patent Litigation

Electromechanical device design Semiconductor fluid pump design Engine design

Geothermal

Turbine failures Construction injuries Large diameter piping failure Downhole casing corrosion/erosion Well head equipment ruptures Corrosion assessment of piping

Construction

Root cause and dispute resolution Design and fabrication review Construction oversight Flaw acceptance/fitness-for-service review Weld procedure specification review Inspection reviews/audits Structural collapses Crane collapses and failures Prestressing equipment failures Concrete placing equipment failures Water supply discoloration Highway bridge failure

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Delay and damage assessments Power tool hand injuries

Environment

Ground motion damage Adhesive flammability Plumbing and re-bar corrosion Copper pipe corrosion Underground structure collapse Pollution/toxics control Alternate energy source evaluation Waste analysis Water treatment analyses Chemical risk assessment and prevention Chemical handling, recycling, and disposal Detection, identification, and treatment of chemical intrusions in sensitive water environments Corrosion analysis, testing, and monitoring State/Federal right-to-know law program development EPA/Resource Conservation Recovery Act program development Modeling of chemical systems

Commercial & Residential

Sprinkler system failures and consequences Sodium hydrosulfite container fire Natural gas diffusion and explosive mixture formation Natural gas explosion in building Propane migration through soil and building explosion Roof collapse Water damage from corroded, leaking pipes Air conditioning system design failures Underground electrical cable failures Electrical switchgear arcing and explosion Natural gas engine valve wear and cracking Water tank float valve failure Water tank support structure damage evaluation

Appliances

Warm air furnace design defects and fire Water heater CO poisoning Warm air furnace and water heater in building explosion Oven door burn injury 13

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Restaurant grill and ventilation duct fire Floor furnace house fire Deep fat fryer control failure and fire Line voltage thermostat evaluation Wall furnace evaluation Swimming pool heater fouling and fire Electric coffee maker failures and fires Range/oven CO poisoning

Personal Injury

Sports equipment failures Medical equipment failures Prosthetic implant failures Escalator-related injuries Ski lift failures Electric shock Cement mixing truck hand injury Machinery guarding issues Machinery pinch point injuries Ladder and chair collapse LPG cylinder fire Glass container and window failures Ammonia cylinder explosion Propane cylinder fire Gas appliance asphyxiation and CO poisoning

Transportation

Brake and suspension failures Operation-related accidents Engine fires Tractor failures Train collisions and accident reconstructions Bicycle component failures Power boat accident Spot weld failure and consequence analyses Drive component failures Liftgate accident Dock leveler accident Railroad tank car derailment and toxic release Gas and hydrocarbon liquids pipeline failure analysis

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Marine & Ocean Engineering

Ship construction and repair Ship stability analysis Damaged vessel analysis Machinery operation and maintenance Power plant design and operation Ship life extension programs and economic analyses Safety equipment evaluation Life extension for liquid natural gas/ liquid petroleum gas (LNG/LPG) carriers

Nuclear Power Generation

Steam generator tubing failures Turbine blade and casing failures Diesel generator failures and generator problems Pipe cracking (IGSCC) Water chemistry analysis; hydrogen water chemistry Analysis of boiling water reactor containment Off-normal primary and secondary water chemistry effects Weld quality surveillance, assessment, and assurance Reactor pressure vessel consequence evaluations Contract warranty assessments and equipment performance evaluations Pipe support failures Risk analyses; probabilistic risk analysis reviews Leak-before-break analysis Seamed stainless steel piping weld analysis Material selection for corrosion resistance Service water system degradation analysis

Aircraft & Aerospace

Gas turbine disc failures Engine failures Flight control problem Space station battery fitness-for-purpose Landing gear failure Corrosion problems Fastener failure Wing-skin failure Mid-air collision Helicopter gears and rotor failures Auxiliary power unit failures

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Section 4 STAFF QUALIFICATIONS

PTECH's strength is our staff--our engineers average over 20 years of experience in their technical specialties. Our professional staff members are listed below, with biographical abstracts. This list ranges from our senior staff members who can serve as expert witnesses in depositions and trials, to our junior personnel who provide technical support for claims and litigation projects. Complete resumes of all APTECH staff members are available on request.

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Kimble J. Clark B.S., M.S., Ph.D. -- Vice President Expertise: Mechanical engineering; heat transfer; fluid mechanics and thermalhydraulics;

combustion and chemistry; fluid transport and thermophysical properties; fires and explosions; accident investigation and reconstruction; failure root cause determination; chemical process analysis and optimization; run/repair/replace decision making; engineering analysis, laboratory testing, and full-scale field testing in the above areas.

furnace explosion; heat-treating salt bath explosion; chemical warehouse fire; elevator fire; vehicle fires; water heater fires; boiler waterwall tube corrosion failure; boiler superheater tube creep failure; diesel engine failure; steam turbine failure; heat exchanger failure; boiler performance testing; industrial refrigerator performance testing; patent infringement on semiconductor fluid pump design.

Projects: Chemical (ammonium perchlorate) plant explosion; refinery hydrogen explosion; glass

Geoffrey R. Egan B.E., D.I.C., Ph.D. -- President Expertise: Applied mechanics; fatigue, fracture, and stress analysis of welded structures involving

piping and pressure vessels, offshore platforms, bridges, and steel framed buildings.

elements; railroad tank car derailment and toxic spill; provided expert testimony for disputes involving airport, hospital, and refinery construction; pumped storage project penstock failure; nuclear power plant piping replacement; failure analysis of coal-fired power plant equipment; nuclear power plant pressurized component failure analysis; nuclear power plant "safe end" analysis; refinery component failure analysis; chemical plant fire and explosion.

Projects: Crane failure analyses; oil and gas pipeline fractures; cracking in bridge structural

Richard J. Schreiber B.S., M.S., P.E., C.F.E.I. Expertise: Mechanical engineering; analysis of failures of mechanical devices that lead to accidents,

losses, fires, and explosions; combustion; energy systems engineering; fuel switching; applied heat transfer; fire and explosion accident investigation; thermal systems instrumentation and testing.

Projects: Utility boiler explosion; gas turbine combustor flashback; propane gas migration and explosion; mechanical seal failure and vessel explosion; chemical (ammonium perchlorate) factory

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explosion; chemical warehouse fire; home furnace, range/oven, and pool heater fires; elevator fire; truck tire/rim injury; package boiler explosion; paper mill injury; machine tool injuries; electrical shock injury; industrial refrigerator performance evaluation; vehicle fires; power plant cycling performance and damage evaluation; patent infringement of semiconductor fluid pump design; oil well fire and explosion; railroad tank car derailment and toxic spill; deep fryer fire; gas main piping explosion; gas pressure regulator failure; tank float valve failure.

Eric V. Sullivan B.S., P.E. Expertise: Metallurgical engineering; welding engineering; failure analysis; nondestructive

examination; field testing and instrumentation; nuclear power plant materials engineering; mechanical testing; OSHA 1910.120 hazardous materials management and emergency response training.

Projects: Power plant component cracking; hydroelectric plant vessel failure and explosion; mining equipment failures; diesel and natural gas engine operation and metallurgy; chemical factory explosion; light aircraft crash; train derailment; gas turbine blade failures; natural gas filter vessel failure and fire; underground gas main piping explosion; vehicle fire. Philip M. Besuner B.S., M.S. Expertise: Mechanical engineering; statistics and probability; applied mechanics related to fatigue,

dynamics, reliability, and stress analysis. Principal developer of the BIGIF computer program for advanced fracture mechanics analysis. Development of statistical estimation techniques to forecast and improve failure rates and costs of mechanical components.

Projects: Aircraft engine disk and blade failures; electric utility component failure prediction; offshore structure fracture control projects; aircraft structure fatigue; railroad defect probability analysis; reliability analysis of a wide variety of other components, including power plant pressure parts and auxiliaries, automobiles, and biomedical equipment. Thomas D. Burnett B.S. Expertise: Fossil utility boiler, steam turbine operation and maintenance; marine engineering.

procedures; coal ball mill failure; pulverized coal piping fire; power plant structural collapse; lime kiln drive chain failure.

Projects: Equipment and component failures; critique of plant operating and maintenance

Russell C. Cipolla B.S., M.S., P.E. Expertise: Mechanical engineering; advanced applications of fracture mechanics; remaining life

prediction methods; ductile fracture of metals; integrity of structures containing flaws; and fitness-forpurpose analysis. Finite element and singular integral equations analysis techniques; elastic-plastic and fully plastic analysis methods; transient heat transfer and thermal stress analysis; member of American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code Section III and Section XI.

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Projects: Fatigue and fracture evaluation of gas turbine disk failure; fatigue prediction of diesel engine connecting rod failure; nuclear plant piping replacement prudence; propeller shaft failure; missile launcher fracture control plan; ladder failures; forklift accident; bolting failures; gear failures; automobile suspension components; helicopter blades. Marvin J. Cohn B.S., M.S., P.E. Expertise: Civil and metallurgical engineering; stress analysis; seismic qualification of equipment;

member of ASME code committees; QA auditor (ANSI N45.2.23).

Projects: Earthquake buckling of storage tank; heat exchanger brazing failure; high energy piping

and headers stress analysis; stress analysis of buried piping systems; catastrophic pipe failure accident reconstruction.

Michael T. Cronin B.S., B.S., P.E., C.W.I. Expertise: Mechanical engineering; analysis of steady-state and transient stress, strain, and

temperature fields using finite element and finite difference methods; fatigue and fracture analysis; risk analysis procedures for making run/repair/retire decisions; nondestructive examination using ultrasonic, magnetic particle, and radiographic methods; non-linear stress and heat transfer analysis. AWS CWI Certificate 97120771.

Projects: Fitness-for-service analysis of steel framing; stationary diesel engine failure; vessel

explosion by autorefrigeration; steam turbine and generator failure; bridge collapse; grain silo collapse; aircraft engine fan disk failure; hotel walkover collapse; fabric dryer explosion; natural gas pipeline rupture; drilling rig collapse; chemical process vessel fracture control plans; railroad collision; space station and satellite battery fracture control plans; helicopter rotor shaft failure.

Rodney L. Dail B.S. Expertise: Metallurgical engineering; welding engineering; failure analysis; mechanical testing;

nondestructive examination; corrosion engineering; technical training.

nylon processing vessel explosion; pickling solution heater explosion; process plant equipment failures and explosions; power plant piping; equipment and boiler component failures.

Projects: Failure analysis of 50,000 ton forging press; nuclear plant piping replacement prudence;

Kenneth A. Ecoffey B.S. Expertise: Mechanical engineering; thermodynamics and heat transfer.

traction injury; noise assessment; life assessment of high temperature/pressure components.

Projects: Coal pulverizer failure; boiler tube failure analysis; tractor tire explosion injury; floor

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Yogendra S. Garud B.S., M.S., Ph.D. Expertise: Mechanical engineering; machine design; material science; elastic plastic analysis. Projects: Stress corrosion cracking and corrosion fatigue damage to heat exchangers, piping, and pressure vessels; materials assessment for high temperature service. Darby A. Gray B.S., M.S., P.E., C.F.E.I. Expertise: Mechanical and electrical engineering; root cause failure analysis of process control

systems and equipment; fires and explosions. (Consulting Associate.)

Projects: Chemical process plants; asphalt mix and blending plants; petrochemical refineries; bulk

petrochemical storage, transportation, and marketing facilities; flammable dust-producing industrial and agricultural processes; heat and flammable gas-producing organic decomposition processes; vehicle tire compounding facilities; explosives manufacturing or utilization processes; automotive service and repair installations.

Russell B. Green B.S. Expertise: Chemical and plastics engineering; thermoplastic and thermosetting resins, polymeric

coatings and adhesives. Thirty-four years with Monsanto Corporation. (Consulting Associate.)

Projects: Plastic products failure analysis for industries including medical, computer, business

machine, automotive, packaging, pipe, and construction; plastics product development.

G. Paul Grimsrud B.S., M.S. Expertise: Engineering economics; utility system planning and operation; system simulation,

optimization, regulation, and rates.

Projects: Damage calculation for power plant unavailability case including delays in unit start-ups, extensive forced outages, and consequential damages; development of cost-of-cycling methods; benefit/cost calculations of numerous electric utility technology options; development and use of utility system planning models. Jeffrey L. Grover B.S., P.E., C.W.I. Expertise: Civil and mechanical engineering. AWS CWI Certificate 97120831. Projects: Airport and refinery construction dispute resolution; flaw evaluations for bridges,

penstocks, ships, steel framing, cryogenic valves, power plant components, and wind tunnel piping; offshore structures corrosion fatigue evaluation; piping failures; codes and acceptance criteria.

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Kevin G. Hara B.S. Expertise: Mechanical engineering; fossil utility boiler design, operation, and economics. Projects: Utility boiler explosion; life assessment of high temperature/pressure components; economic trade-off studies; plant betterment; coal pulverizer failure; impact of cycling and deration on plant life and reliability; heat recovery steam generator failure. Robert J. Impey B.S. Expertise: Mechanical engineering; power plant operation. Projects: Coal pulverizer failure; package boiler explosion; frost damage in paper mill; chemical

plant explosion; food processing plant fire; diesel engine explosion; industrial and utility boiler explosions; stationary and marine boiler troubleshooting.

Stephen M. Kohan B.S., M.S., Ph.D. Expertise: Chemical engineering; risk analyses; chemical process modeling. Projects: Catalytic cracker accident; petroleum refinery testing; refinery methods improvement program; gas drying to satisfy DOT regulations; geothermal, wind, biomass, and solar power plants; catalytic conversion of natural gas to liquid; cogeneration case studies; economic model critique and development. Todd A. Kuntz B.S., M.S., P.E., C.W.I. Expertise: Metallurgical/materials engineering. AWS CWI Certificate 97120891. Projects: Airport and refinery construction dispute resolution; power plant instrumentation for damage monitoring; bicycle suspension failure; piping failures; structural welding certification; trailer hitch failure. Clayton Q. Lee B.S., M.S., P.E. Expertise: Mechanical engineering; thermodynamics and heat transfer. Projects: Glass furnace explosion; power plant remaining life; industrial refrigeration performance testing; power plant component failures; loading dock injury; impact of cycling and deration on plant reliability; nuclear check valve failure; elevator fire; coal pulverizer failure; risk analysis of lead contamination from submersible pumps. Steven A. Lefton B.S. -- Vice President Expertise: Chemical and mechanical engineering; management and operational expertise in fossil

and nuclear utility power plants, including the construction, start-up, and on-line operational

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procedure writing and check-out of power plant equipment; fuel handling and fuel burning equipment; calibration and design of utility boiler-turbine control systems. Expertise in water treatment and boiler water control measures used to prevent deposition and corrosion damage to power plant equipment.

Projects: Evaluation of boiler manufacturer design processes; boiler water chemistry practices; Public Utilities Commission testimony on utility boiler ratings; impact of cycling and deration on plant life and reliability; fossil utility boiler explosion investigation; failure analyses of turbines, diesel engines, ball mill bull gear, and tubes; analysis of air preheater failure and proposed redesign. Philip B. Lindsay B.S., M.S., P.E. Expertise: Metallurgical and corrosion engineering; materials selection; development of corrosion

test laboratory technology; corrosion failure analyses; field corrosion testing; applied research in ferrous alloy development; corrosion engineering group supervision; powder metallurgy fabrication; transmission and scanning electron microscopy analyses; computer analysis of engineering data and metallurgical instruction.

Projects: Residential water pipe contamination ("blue water"); soil corrosion; home foundation

failure; corrosion of reinforced concrete; heat exchanger failures -- feedwater heaters, condensers, service water heaters; ammonium nitrate plant explosion.

Richard S. Moser B.S. Expertise: Metallurgical engineering; nondestructive testing; remaining life assessment;

development of mechanical field testing techniques.

Projects: Pressure vessel corrosion and failure; power plant tubing failure analysis; railroad tank car rupture; welded structure failures; oil well fire and explosion; natural gas engine valve wear and cracking. Steve R. Paterson B.S., M.S., C.W.I. Expertise: Metallurgical engineering; welding engineering; mechanical testing; failure analysis;

nondestructive examination; fractography; theoretical and experimental fracture mechanics; analysis of material degradation; and forensic engineering. AWS CWI Certificate 97120921.

evaluation of structural steel framing weldments for hospitals, airports, and bridges; ASME B31.1, B31.3, and B31.4 piping weld quality v. NDE; railroad safety appurtenances and structural members; hydroelectric penstock failures; steam piping failures; construction claim evaluations.

Projects: Boiler tubing failure analysis; author of guide for boiler tube metallurgical failure analysis;

Terry W. Rettig B.S., P.E. -- Vice President Expertise: Metallurgical engineering; failure analysis of power plant, automotive, and aircraft

components; materials selection and methods of fabrication and processing; corrosion and metallurgical failure of alloys; nondestructive inspection by acoustic emission.

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Projects: Railroad tank car explosion; helicopter crash; power plant pressure parts failures; aircraft

component failure analysis; scaffolding accident; coal pulverizer failure; chain failures; automobile and truck accidents.

T. Steven I. Torbov B.S., M.S. Expertise: Mechanical engineering; power plant design, operation, and materials selection. Projects: Diesel engine failure; evaluation of industrial burner systems; boiler explosions; low NOx

burner malfunctions; boiler performance testing; boiler water circulation model; boiler tube and header failure analysis; steel mill coke oven gas explosion; boiler fire.

Phillip L. Wheeler B.S., M.S., P.E. Expertise: Electrical engineering; electrical power systems. (Consulting Associate.) Projects: Failure analyses of power electrical equipment in substations, transmission lines, interconnections, switchgear, cables and power plants; residential appliances and commercial equipment failures and fires. James J. Yavelak B.S., M.S. Expertise: Metallurgical engineering; power plant high pressure and temperature components. Projects: Utility boiler pressure vessel rupture; railroad metallurgy and accident reconstruction; nuclear steam generator evaluation; in-the-field condition assessment of power plant components; boiler metallurgy troubleshooting; failure of dye filter vessel.

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Section 5

REFERENCES

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he references listed below represent a cross-section of APTECH clients. These clients are familiar with the capabilities and credentials of APTECH. Additional references can be provided upon request. Cal Erectors, Bay Area, Inc.

Mr. Dave McEuen 4500 California Court Benecia, California 94510 Telephone: (707) 746-1990 Root cause analysis/dispute resolution

Carroll, Burdick & McDonough LLP

James W. Henderson, Esq. 400 Capitol Mall, Suite 1400 Sacramento, California 95814 Telephone: (916) 446-2222 Railroad car retention pedestal analysis

Chubb Group of Insurance Companies

Mr. Earl Carroll Specialist Claims Examiner Chubb Group of Insurance Companies 5098 Foothill Boulevard, 3-130 Roseville, CA 95747 Telephone: (916) 772-9263 Gas turbine blade failures Underground electrical cable failure Poultry chiller equipment wear and tear Laser cutting machine reliability/repair Poultry feed mill malfunction Hydroelectric plant explosion Forging equipment cracking

Clapp, Maroney, Bellagamba, Davis & Vucinich

Mr. Robert Bellagamba, Esq. 4400 Bohannon Drive, Suite 100 Menlo Park, California 94025 Telephone: (415) 327-1300 Residential copper piping corrosion ("Blue Water")

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Clausen, Miller

Mr. Thomas McDonald, Esq. Mr. Kevin Caraher, Esq. Mr. George Zelcs, Esq. 10 South LaSalle Street Chicago, Illinois 60603 Telephone: (312) 855-1010 Ethylene plant heat exchanger failure Fertilizer plant explosion

Crawford-THG

Mr. Bill Hemmelsbach 1255 Market Street, Suite 1220 San Francisco, California 94015 Telephone: (415) 977-1863 Gold mine air heater failure

Cullom, Burland, Bacon & Overpeck

Mr. Jacob Burland, Esq. 635 Sacramento Street, Suite 720 San Francisco, California 94111 Telephone: (415) 781-7999 Elevator fire accident reconstruction Condominium fire

Desimone, Chaplin & Dobryn

Mr. Frank Marino, Esq. 901 Battery Street San Francisco, California 94111 Telephone: (415) 398-5740 Flaw acceptance/fitness-for-service review; construction oversight; design for seismic upgrade

Diepenbrock, Wulff, Plant & Hannegan, LLP

Mr. D. Michael Schoenfeld, Esq. 300 Capitol Mall, Suite 1700 Sacramento, California 95812-3034 Telephone: (916) 444-3910 Weld quality audit; fitness-for-service review; dispute resolution

Ernest Brown & Company

Mr. Ernest Brown Mr. William Marquis AT&T Building 8001 Irvine Center Road, Suite 970 Irvine, California 92718 Telephone: (714) 727-0559 Power plant steam line rupture

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Fabian & Clendenin

Mr. Stanford Owen, Esq. 215 South State Street, 12th Floor Salt Lake City, Utah 84151 Telephone: (801) 531-8900 Utility boiler performance dispute

Factory Mutual

Mr. Dwight Hinton 5445 Seventy-Seven Center Drive, Suite 60 Charlotte, North Carolina 28217 Telephone: (704) 525-9000 Sulfuric acid plant failure

Global Claims Services Corporation

Jerry R. Simmons 6480 Rockside Woods Blvd., South Cleveland, Ohio 44131-2206 Telephone: (216) 447-1600 Ethylene plant pressure vessel failure

Hughes & Luce

Mr. Douglas A. Cawley, Esq. 1717 Main Street, Suite 2800 Dallas, Texas 75201 Telephone: (214) 939-5500 Patent infringement: semiconductor manufacturing fluid pump

Industrial Risk Insurers

Mr. Seale Tuttle 85 Woodland Street Hartford, Connecticut 06105 Telephone: (203) 520-7383 Ethylene plant pressure vessel failure

Jenkins & Gilchrist

Mr. Jeffrey Bacon, Esq. 1445 Ross Avenue, Suite 3200 Dallas, Texas 75202-2799 Telephone: (214) 855-4757 Patent infringement: semiconductor manufacturing fluid pump

Maxson Young Associates, Inc.

Mr. Edwin Baker, V.P. One Sansome Street, Suite 950 San Francisco, California 94104 Telephone: (415) 392-6034 Gas-fired utility boiler explosion Gas turbine flashback

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McClintock, Weston, Benshoof, Rochefort, Rubalcava & MacCuish, LLP

Mr. Mark Rochefort, Esq. 5385 Hollister Avenue Goleta, California 93111 Telephone: (805) 962-1688 Evaluation of welding and quality issues; dispute resolution

McLarens Toplis North America, Inc.

Mr. Ken Cruikshank 600 Jefferson, Suite 1000 Houston, Texas 77002-7335 Telephone: (713) 752-0714 Pharmaceutical plant pressure vessel failure

Millenium/WDG

Mr. Mark Farrar 100 First Street, Suite 2350 San Francisco, California 94105 Telephone: (415) 896-2300 Flaw acceptance; fitness-for-service review; construction oversight; design for seismic upgrade

Murphy and Beers

Mr. Tim Murphy, Esq. 1939 Harrison Street Oakland, California 94612 Telephone: (510) 597-3303 Building explosion Gas pipeline fracture

Parsons Infrastructure & Technology Group, Inc.

Mr. Jeff Palmquist 3225 North Harbor Drive San Diego, California 92101 Telephone: (619) 297-9988 Weld quality audit; fitness-for-service review; dispute resolution

PDM Strocal

Mr. Fred Long 2324 Navy Drive Stockton, California 95206 Telephone: (209) 948-4600 Weld procedure specification dispute

Pearson Christensen

Mr. Richard Clapp, Esq. 24 North 4th Street Grand Forks, North Dakota 58206 Telephone: (701) 775-0521 Agricultural chemical warehouse fire caused by vehicle fire Mobile home fire Aircraft refueling fire

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Public Service Company of Colorado

Mr. William M. Dudley Assistant General Counsel Post Office Box 840 Denver, Colorado 80201-0840 Telephone: (303) 294-2500 Testimony before Public Utilities Commission on power plant operation costs

Robins, Kaplan, Miller & Ciresi

Mr. David Bocan, Esq. 444 Market Street San Francisco, California 94111 Telephone: (415) 391-9799 Turbine failures Ski lift equipment failure

Schuff Steel

Mr. Don Engler 420 South 19th Avenue Phoenix, Arizona 85009 Telephone: (602) 251-0314 Root cause analysis; design and fabrication review

Sedgwick, Detert, Moran & Arnold

Mr. Anthony Anscomb, Esq. Mr. Steven Burke, Esq. One Embarcadero Center Sixteenth Floor San Francisco, California 94111 Telephone: (415) 983-5600 Power plant valve failure and asbestos release (Moss Landing Power Plant) Natural gas pressure regulator evaluation

Thorndal, Backus, Maupin & Armstrong

Mr. Eugene Backus, Esq. Post Office Drawer 2070 1100 East Bridger Avenue Las Vegas, Nevada 89125-2070 Telephone: (702) 366-0622 Natural gas pipeline rupture and oxidizer (ammonium perchlorate) plant explosion (PEPCON)

Zelle & Larson

Mr. Lawrence Zelle, Esq. Mr. Thomas Darden, Esq. 33 South Sixth Street Minneapolis, Minnesota 55402 Telephone: (612) 339-2020 Turbine failure Ethylene plant pressure vessel failure Fertilizer plant explosion

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Section 6

CLIENT LIST

Legal & Insurance Clients

Aero Adjustors Aetna Life and Casualty Company Air Products & Chemicals, Inc. Allstate Insurance Company American Sentinel Insurance Agency Archer, McComas & Lageson Arkwright Insurance Company Audley & Pandullo Babin, Seeger & Byrne Badal, Wetteroth & Gordenev Baker & Botts Baker & Daniels Baker & MacKenzie Bishop, Barry, Howe, Haney & Ryder Blackwell, Sanders, et al. Brobeck, Phleger & Harrison Buchman, Kass & Miller Burke, Ashford, Sakai, et al. Butey, Locas, Dunn & Enright Cal Comp Insurance Company Carey & Carey Carniato & Dodge Carroll, Burdick & McDonough Chase, Rotchford, Drukker, Bogust Chubb Group of Insurance Companies Cigna Insurance Clapp, Maroney, Bellagamba, et al. Clausen, Miller CNA Insurance Companies Cole & Cole Condon & Forsyth Continental Insurance Cooper, White & Cooper Cozen & O'Connor Crawford-THG Cresswell, Davis, Cake & McNeely Cullom, Burland, Bacon & Overpeck Davis, Polk & Wardwell Denenberg, Tuffley & Bocan Dinkelspiel, Donovan & Reder

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D.L. Glaze Company, Inc. Donovan, Leisure, Newton & Irvine Dorr, Cooper & Hayes Downey, Brand, Seymour & Rohwer Ericksen, Mackenroth, Arbuthnot, et al. Ernest Brown & Company Fabian & Clendenin Factory Mutual Farbstein Law Corporation Field & Field Fireman's Fund Insurance Company Fisher, Gallagher, Perrin & Lewis GAB Insurance Company Girardi & Keese Global Claims Service Corp. Gordon, Edelstein, et al. Hall, Farley, Oberrecht, and Blanton Harris & Riggs Hassard Bonington LLP Herzfeld & Rubin Holbrook, Lankes & Groff Industrial Risk Insurers (IRI) Insurance Company of North America Johnson & Wortley Kaufman & Broad Kemper Insurance Company Kincaid, Gianunzio, Caudle & Hubert Kinnard & Smith Kirkpatrick & Lockhart LLP Knipmeyer, McCann, Smith, et al. Lamorte, Burns and Company, Inc. Lane, Powell, Spears & Lubersky Liberty Mutual Insurance Company Lord, Bissell & Brook Maloney & Associates Maxson Young Associates, Inc. McClintock, Weston McLaren Toplis North America Miller, Canfield, Paddock & Stone Murphy & Beers 31

Nixon, Hargrave, Devans & Doyle Northbrook Property & Casualty Insurance Company Owens-Illinois Legal Department Ramirez & Ramirez Reliance National Insurance Company Rice, Fowler, Kingsmill, Vance Richard White, Law Offices Ridenour, Swenson, et al. Robins, Kaplan, Miller & Ciresi Roeca, Louie & Hiraoka Ropers, Majeski Royston, Razor, Vickery & Williams Sedgwick, Detert, Moran & Arnold Schiff, Hardin & Waite Sidley & Austin Thoits, Lehman & Love

Thomas Howell Group United Airlines Legal Department Vargas & Bartlett Walkup, Downing, Shelby, et al. Walther, Key, Maupin, Oats, Cox, et al. Ware, Fletcher, Friedenrich Washington Public Power Supply System Western Pioneer Insurance Company Wilson, Elser, Moskowitz, et al. Winingham, Roberts, Fama, et al. Winston & Strawn Winthrop, Stimson, Putnam & Roberts Wray, Robinson & Kracht Zelle & Larson Zenith National Insurance Company

Petroleum, Chemical, & Industrial Clients

Acuson Computed Sonography Adams, Smith & Graff Aerospace Corporation ALCOA Allied Signal, Inc. Alzeta Corporation American Oilfield Divers, Inc. Amoco Oil Company Amoco Research Center Apple Computer Applied Materials ARB, Inc. ARCO Chemical Company Badger Engineers, Inc. BP Exploration, Inc. Celeron Pipeline Champion International Corporation Chevron U.S.A., Incorporated CITGO Petroleum Corporation Collagen Biomedical Company Commercial Machine Works Composite Microwave Coors Brewing Company Dow Chemical Dresser-Rand ENPRO Systems, Inc. Envirogenics Equatorial Communications Company Exxon Company, U.S.A.

FMC Corporation Ford Aerospace and Communications Genentech Glenrock Coal Company Graphics Microsystems, Inc. Gulf Chemical & Metallurgical Corporation Hewlett Packard Hoechst-Celanese Corporation Inhale Therapeutics Systems Intel Corporation International Communications Agency International Paper Company KLA Instruments Corporation Marathon Oil Company Masonite Corporation MCR Geothermal Corporation Microalloying International Microscience International Corp. Millenium Partners Moorfeed Corporation National Semiconductor Occidental Chemical Corporation Oman Oil Company OxyChem PetroCanada Plantronics Sandoz Pharmaceuticals Shell Oil Company

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Shell Western E&P, Inc. SOHIO Construction Space Systems/Loral Standard Alaska Production Suncor, Inc. Syncrude Canada Todd Shipyards

Total Petroleum Transamerica Delaval Tren-Fuels, Inc. Union Oil Company United States Steel Corporation VICO Services, Inc.

Electric Utility Clients

Alabama Power Company American Electric Power Company Arizona Electric Power Cooperative Arizona Public Service Company Associated Electric Cooperative Atlantic City Electric Company Basin Electric Power Cooperative Bechtel Power Corporation Boston Edison Company Brazos Electric Power Corporation Brown Boveri Power Equipment Brown & Root Burns & McDonnell Cajun Electric Power Cooperative Carolina Power & Light Company Centerior Service Company Central Illinois Lighting Company Central Illinois Public Service Central Louisiana Electric Company Chugach Electric Association Cincinnati Gas & Electric Company City of Austin, Texas City of Bryan, Texas City of Burbank, California City of Garland, Texas Colorado Ute Electric Association Consolidated Edison Company Consumers Power Company Container Corporation of America Combustion Engineering C.T. Main, Inc. Dayton Power & Light Delmarva Power Company Deseret Generation & Transmission Cooperative Detroit Edison Company Duke Power Company Duquesne Light Company Ebasco 33

Electric Energy, Inc. Electricite de France Eskom (South Africa) Florida Crushed Stone Company Florida Power Corporation Florida Power & Light Company General Electric Company Georgia Power Company Gilbert Associates Gilbert Commonwealth, Inc. GPU Nuclear Corporation Gulf States Utilities Company Hawaiian Electric Company Hawaii Electric Light Company High Mountain Inspection Service Houston Lighting & Power Company Illinois Power Company Indianapolis Power & Light Iowa-Illinois Gas & Electric Iowa Public Service Company Israel Electric Corporation Jacksonville Electric Authority Japan Technical Services Corp. Kansas City Power & Light Kansas Gas & Electric Company Laidlaw Gas Recovery Los Angeles Dept. of Water & Power Louisville Gas & Electric Company Medina Electric Cooperative Mississippi Power & Light MQS Inspection, Inc. Muscatine Power & Water Nevada Power Company New England Electric Power New York Power Authority New York State Electric & Gas Niagara Mohawk Power Corp. Northeast Utilities Service Company Northern Indiana Public Service

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Ohio Edison Company Oklahoma Gas & Electric Company Omaha Public Power District Orange & Rockland Utilities, Inc. Outokumpu EcoEnergy, Inc. Pacific Gas & Electric Company Pacific Power & Light Company Pennsylvania Electric Company Pennsylvania Power Company Philadelphia Electric Company Plains Electric Generation & Transmission Cooperative Portland General Electric Company Potomac Electric Power Company Power Plant Specialists, Inc. Public Service Company of Colorado Public Service Company of Indiana Public Service Company of New Mexico Public Service Company of Oklahoma Public Service Electric & Gas Puerto Rico Electric Power Authority Pyropower Corporation Queensland Electricity Commission (Australia) Riley Stoker Corporation Rochester Gas & Electric Company

Salt River Project San Diego Gas & Electric Company Sargent & Lundy Sierra Pacific Power Company South Carolina Electric & Gas Southern California Edison Southwestern Public Service Tennessee Valley Authority Texas Power & Light Company Texas Utilities Electric Company TU Mining Company Turbine Consultants, Inc. Ultrasystems Engineers & Constructors Union Electric Company US Generating Company Utah Power & Light Company Vermont Yankee Nuclear Power Virginia Electric & Power Company Washington Public Power Supply System Western Farmers Electric Cooperative Westinghouse Hanford Company Westinghouse Savannah River Wolf Creek Nuclear Operating Corporation, Inc. Wolverine Power Supply Cooperative

Government/Institute Clients

Argonne National Laboratory Edison Welding Institute Electric Power Research Institute Gas Research Institute Gates Energy Products, Inc. General Dynamics Space Systems Division Lawrence Livermore Laboratories Materials Technology Institute NASA/AMES Research Center Occidental Research Corporation

Stanford University United States Department of Air Force United States Department of Defense United States Department of Energy United States Department of Navy United States Department of Transportation United States Nuclear Regulatory Commission University of California at Los Angeles Welding Research Council

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Section 7

CASE SUMMARIES -- GENERAL

Boilers and Power Plants

Suitability-for-Service Evaluation of Seam Welded Heating Boilers

In this project, APTECH provided ASME Boiler and Pressure Vessel code interpretation on the acceptance of lap joints for Section IV heating boilers. Although a butt weld design is specified by ASME Section IV, a lap joint was approved by the authorized inspector assigned to review the vendor design. As a result, a technical dispute had developed between the manufacturer and the National Board of Inspectors over the code certification of approximately 8000 boilers currently installed. APTECH assisted the manufacturer in resolving the technical issues by verifying that the structural integrity of the lap joint design was adequate and by obtaining code approval for a code case regarding alternate rules for lap joint fabrication. Passage of the code case effectively allowed the existing 8000 heating boilers to maintain code certification.

Intergranular Stress Corrosion Cracking in Nuclear Power Plant Reactor Components

In this project, APTECH performed a detailed evaluation of the propensity for intergranular stress corrosion cracking (IGSCC) of Inconel 600 components in nuclear power plants (BWRs). These particular components, the thermal sleeve and safe end, had shown significant cracking at other plants prior to start-up. Plant management decided to remove and replace the components prior to start-up. APTECH performed an historical document review to establish the necessity for such action, and evaluated the likelihood of IGSCC in existing and alternate materials. APTECH also provided deposition and trial testimony for this project.

Hydroelectric Penstock Failure

A 30-foot diameter penstock failed catastrophically during "water-up" of a large pumped storage hydroelectric plant in California. APTECH was hired by the supplier of the penstock to find the cause of the failure. The issues that APTECH investigated related to weld quality and workmanship, structural significance of welding defects, and the reliability of inspection techniques to locate critical flaws. Issues of material properties and fracture toughness, in particular, were evaluated. A structure integrity reconstruction of the accident was performed. This reconstruction of the existing conditions at the time of the accident led to the conclusion that significant additional stresses were imposed on the system by the foundation settlement. APTECH provided expert testimony to this effect in the subsequent trial.

Power Plant Generator Failure

APTECH was employed by an insurance company to provide a third-party opinion regarding generator rotor tooth top cracks and retaining ring indications. Field metallography, engineering report review, and interviews of plant personnel formed the basis of APTECH's conclusions. We presented expert opinion regarding the cause and structural significance of the NDE indications and cracking.

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Power Plant Cycling and Derating Analysis

APTECH engineers have performed a number of projects to quantify the effect of cyclical operation and derating on the lifetime and reliability of electric power plants. A typical project begins with a detailed review of the plant's operating and outage records, followed by an on-site engineering examination of the plant to establish its current condition. This information is factored into a proprietary statistical analysis process which determines the economic impact of cycling operation and derating. Our results are used by the client to judge whether cycling or derating are feasible or if other power generation alternatives should be considered.

Pipeline Fracture Control

Recently, several gas pipeline projects have been proposed that would require the pipe to have wall thickness much greater than 1 inch and operate at pressures in excess of 5000 psi. APTECH participated in the development of a fracture control plan for one of those pipeline projects. The design constraints were: a maximum operating pressure of about 6000 psi, wall thickness ranges between 1 and 2 inches, and a deep water depth of over 11,000 feet. These design conditions imposed constraints on the fracture requirements that are not addressed in standard pipeline fracture control procedures. APTECH's approach to the problem was to review the basis for the existing design procedures for gas pipeline fracture control; determine, on a theoretical basis, whether or not they could be extrapolated beyond the range of empirical validation; and identify weaknesses in the approach and make recommendations for improvements or changes in the guidelines. The program results identified the weaknesses in the current design guidelines, but showed that the current guidelines could still be applied provided certain safety factors were included. We also recommended alternative approaches that could be applied as easily as the standard design guidelines. Failure predictions, such as fracture during buckle, were confirmed with full- scale testing. Furthermore, due to the large size of the project (over 1100 kilometers of pipe), the results were incorporated into a risk evaluation of the overall project.

Steam Turbine Failure

At the request of an insurance company, APTECH was retained by a midwestern law firm to investigate the catastrophic failure of a power plant's steam turbine. APTECH performed on-site failure investigations, failure analysis, and attended meetings at the turbine manufacturer's factory. We determined that all components in the intermediate-pressure turbine, including the blades, nozzles, and stationary diaphragms, had been damaged or destroyed. APTECH obtained proposals for replacement components. With APTECH's assistance, this failure was successfully adjusted to the client's satisfaction.

Diesel Engine Failure

APTECH was retained by an insurance company whose client owned a large Navy submarine-type Diesel engine. The diesel engine had suffered mechanical breakdown that consisted of piston and bearing damage. APTECH established the failure mechanism and the cause of failure.

Repetitive Failures of a Roller Bearing in a Radial Hydroturbine

A paper mill in the eastern United States had been experiencing repetitive failures of a 2.5-foot diameter roller bearing in their radial Kaplan hydroturbine. On a recent occasion, the turbine's performance indicated that the bearing had again failed. In response, the plant dismantled the turbine and prepared to repair the bearing. APTECH was retained by the plant's insurance carrier to find the cause of the repetitive failures and to determine if the latest proposed repairs were justified. From our site inspection, records review, and follow-up engineering analyses, we concluded that the 36

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bearing housing was improperly anchored to the foundation. This created a magnitude of axial stress that the roller bearing was not designed to withstand, which eventually led to the numerous failures. Our visual examination and metallurgical analysis of the bearing revealed that it had not yet failed on this particular occasion. Recommendations were made to preclude further failures.

Land Subsidence at Power Plant

A major renovation of the pollution control equipment at a coal-fired power plant was midway through completion. Numerous pieces of heavy construction equipment were on-site, including piledrivers. A massive land cave-in suddenly occurred at the plant site, involving a several thousand square-foot area to a depth of up to 15 feet. Substantial damage occurred to existing and new plant structures and equipment. The cave-in was caused by the collapse of two 22-foot diameter underground cooling water pipes running from the plant to a nearby lake. APTECH conducted a detailed investigation of the power plant design and operation to determine their role in the accident. All plant operating logs just prior to the accident were reviewed in detail to determine if a coolingwater system upset occurred and caused the pipe collapse.

Tube Failures in a Paper Mill Boiler

A major paper and pulp mill experienced degradation of steam tubes in a black liquor recovery boiler. APTECH was retained by the paper mill's insurance carrier to determine if the cause of the tube degradation was due to inadequate boiler design or to plant operations. Our investigation included a site visit, during which time we reviewed plant operations and the recovery boiler design. We also investigated current boiler operating practices and compared these to the design conditions. Recommendations were made to mitigate the degradation.

Process Industries

Environmental Litigation Involving a Major Oil and Chemical Company

A major oil and chemical company sued its insurance companies to recover the cost of environmental compliance in the dozens of states in which it operated. APTECH was retained as part of a team tasked with investigating the validity of the company's claims, totaling over $1 billion. APTECH prepared time lines of critical events at the initial sites to demonstrate the progression of knowledge concerning oil and chemical leaks and spills; and provided litigation support and topical reports as requested.

Environmental Release of Refinery Chemical

As part of a dispute concerning insurance coverage, APTECH was retained to provide expert knowledge concerning refinery hydrocracker design, operating, and maintenance practices. A refiner continued to operate a pressurized refinery column after a leak in the column was discovered by its personnel. APTECH was asked to address the question of whether or not local refinery personnel expected or intended that the leak would migrate or progress offsite. APTECH reviewed the case documentation, conducted a site visit, wrote reports, and provided litigation support.

Chemical Poisoning Inside a Gas Separator Vessel

While manually cleaning out a high pressure sour gas field separator vessel, a worker was injured by inhaling noxious gases. The problem arose when an unexpectedly thick deposit of sediment was encountered on the vessel bottom. During cleanout, noxious gases adsorbed deep within the sediment layer were released when the sediment became disturbed. These gases had been deposited within or upon particles of earth and sediment at high pressures during normal vessel 37

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operation. Unfortunately, the release occurred in the immediate vicinity of workers inside of the vessel. APTECH reviewed the incident documentation and prepared an opinion concerning the origin of the noxious gases and whether or not they could be considered to be pollutants. A manufacturer used conventional high-temperature thermal incineration to destroy volatile hydrocarbon emissions and then recovered thermal energy in a waste heat boiler. To save fuel, he installed a new catalytic oxidation unit (between the incinerator and boiler) that would combust volatile hydrocarbons at lower temperatures. The catalyst never functioned properly because there was no temperature rise across the bed and the operation failed source emissions tests. APTECH was asked to investigate the claims. The results of catalyst testing showed that the catalyst was severely poisoned (surface area of about 0.1 m2/gm) and had a negligible pore volume. APTECH used ESCA (Electron Spectroscopy for Chemical Analysis) to determine the surface composition of the catalyst; the results clearly showed the presence of silicon dioxide. It is well known that noble metal oxidation catalysts are poisoned by heavy metals (e.g., phosphorous, silicon) because they tend to adhere to active catalyst sites. APTECH prepared a report of its findings.

Catalyst Poisoning in Catalytic Oxidation Unit

Deactivation of Steam Methane Reformer Catalyst

An ammonia manufacturer asked APTECH's help in investigating the deactivation of their steam methane reformer catalyst. APTECH reviewed records, catalyst activity data, process flow diagrams, and strip chart recorder data rolls. Also APTECH walked the unit down and held discussions with knowledgeable personnel in management, operations, maintenance, and engineering. APTECH prepared a report recommending the installation of additional equipment items and control interlocks to prevent recurrence of the incident. The manufacturer accepted the recommendations.

Mercury in Natural Gas from Offshore Gas Field

APTECH was asked to develop and prepare the technical case for the owner of an onshore gas conditioning plant that received natural gas containing high levels of mercury from an adjacent offshore gas platform. Mercury is detrimental to the aluminum heat exchangers used in cryogenic separations in the plant. At issue was the performance of a column used to dry natural gas, using triethylene glycol (or TEG), as the dehydrating agent. APTECH measured the mercury content of streams entering and leaving the TEG column. APTECH designed a series of bench-scale experiments at full line pressure to develop a database. Several analytical instruments were used to simultaneously measure the concentration of mercury in vapor streams. Additional experiments were conducted to measure the equilibrium concentration of mercury in common light hydrocarbon gases. APTECH prepared several reports of its findings.

Failure of Oil Well Drill Casing

During a routine hydrotest of a section of high strength steel drill casing, the hydrotest plug separated from the casing causing a personal injury. APTECH performed an in-depth failure analysis of the casing pipe. This involved making detailed dimensional measurements of the thread region, strength measurements, chemical analyses, and metallurgical evaluations (of a crack in the threaded region of the pipe). APTECH provided expert opinion regarding the relative contribution of the features which caused the failure.

Paper Mill Equipment Damage and Production Loss

APTECH was hired by an insurance company to investigate a claim by a paper mill for equipment damage and loss of production. The investigation included records review (operation, production, and shift logs), personnel interviews, and equipment inspection. We found that the damage occurred

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during a five-day period of unusually cold weather. Water inside a support for a critical chemical piping system had frozen, and its resulting expansion had bent and broken the piping above. The absence of this chemical forced the paper machine to slow or shut down, which led to the freeze-up of other components. Our findings were summarized in a time-line format showing the sequence of events that caused the damage and loss of production.

Damage to a Steam Turbine in a Paper Mill

An electric power-generating steam turbine in a southern United States paper mill suffered damage during an unusual period of freezing weather. APTECH was retained to determine the cause of the damage. From our site inspection, records review, and personnel interviews, we determined that the sub-freezing temperature caused a boiler water level-control system to malfunction, which led to overfilling of the boiler. Water from the boiler eventually entered the turbine and damaged the rotor blades. After identifying this failure mode, we then reviewed the turbine manufacturer's repair proposal.

Overheating and Failure of Ore Drying Equipment

A fired heater used to generate hot gas for drying ore in a mining operation overheated and was destroyed. APTECH was retained by the insurance company to find the root cause of the failure. We performed an inspection and engineering analysis of the heater. We then obtained metal and refractory samples and analyzed them in our laboratory. Finally, we reviewed the operation log books and interviewed plant personnel. During this incident, the refractory failed completely and the metal shell buckled and melted.

Failure of a Cyclone Separator in a Mining Operation

A hot-gas cyclone separator used in a mining operation overheated and failed. The separator, installed downstream of a fluidized bed furnace, was operating in a 1300°F environment. APTECH was retained by the mine's insurance company to find the root cause of the failure. A site inspection revealed that the outlet (four-foot diameter) of the separator had deformed so much that it was almost completely closed. We found that this outlet had been fabricated with carbon steel, which was unable to withstand the system's operating temperature.

Glass Furnace Failure

During batch operation, the sidewall of a glass furnace ruptured, releasing 400 tons of hot molten glass. The molten glass flowed into the basement of the plant where it came into contact with an electrical transformer. The heat of the surrounding glass caused the transformer to rupture and release PCB-containing oil over a wide area. The plant was down for several months while repairs and PCB cleanup were accomplished. APTECH performed a complete reconstruction of the accident, tracing the sequence of events from the original furnace rupture to the moment the transformer ruptured. A detailed subscale model of the glass furnace facility was constructed to aid in visually depicting the accident scenario.

Analysis of the Performance of Industrial Refrigeration Equipment

The owners of a large cold storage warehouse alleged that the system's ammonia-based evaporation units were not performing up to the manufacturer's original engineering specifications. The manufacturer's insurance company retained APTECH to evaluate the performance of this equipment. APTECH prepared a test plan, and then installed thermal measurement instrumentation on one of the ceiling-mounted evaporator units. All test activities, which took place in a -10°F environment, were closely monitored by consultants hired by the plant. The test data indicated inadequacies in the system design and plant operating procedures.

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Insulation Panel Failure

The thin aluminum facing on polystyrene insulation panels in a mushroom-growing plant partially delaminated. The delaminization voids filled with water which condensed on the surfaces of the insulation panels due to the high humidity environment maintained in the plant. It was alleged that the water trapped in the delaminization voids became a source of nematodes which would subsequently leak out of the panels, contaminate the compost, and cause a drastic reduction in mushroom yield. APTECH inspected the panels and performed a heat transfer analysis of the compost tunnel and a modification of the original design of this tunnel.

Asbestos Exposure Litigation

APTECH was hired by defense attorneys for a building products company to act as consultants and expert witnesses for an asbestos exposure litigation. This case concerned an individual who claimed health damage due to alleged exposure to the manufacturer's asbestos- containing products. For our first task, we created a computer database of all of the defense's documents and evidence. This allowed us to easily search for key information as the case proceeded. Next, we wrote a protocol for scientifically sampling and analyzing both the company's products and the specific material to which the plaintiff was known to be exposed. Using this protocol, we obtained the samples and analyzed their chemical and physical characteristics. These tests revealed that the company's product had unique chemical constituents that were not found in the plaintiff's material. The analyses also showed that the company's manufacturing process had the side-effect of reducing the toxicity of the asbestos fibers. Our findings were presented during depositions and a subsequent trial in Superior Court. We made extensive use of visual aids and graphics to make the data understandable.

Property Loss

Failure of Water Piping in an Apartment

A 250-unit apartment complex experienced widespread leaks in the hot and cold water piping systems. The reports written by previous experts hired by the builder were inconclusive as to the cause of the failures in this galvanized steel piping. APTECH was hired to take over the investigation. We found extensive internal corrosion during a field examination, and that the failures occurred predominantly in the hot water piping. The root cause of the problem was identified as poor quality of welds and galvanized coatings. We also reviewed the other experts' reports and outlined the needs for additional data to supplement this previous work.

Failure of Water Piping in a Tract Development

The galvanized steel piping systems in over 500 homes had to be replaced by the builder after they developed extensive leaks. APTECH was hired to find the root cause of the piping failures. A field examination revealed internal corrosive attack only on the cold water piping. The pattern of the corrosion was randomly distributed throughout the development. Water chemistry tests were performed and the quality of the pipe was evaluated. We obtained lengths of the corroded piping and found that it had been supplied by numerous different manufacturers. Recommendations were made to the client for a systematic materials test program to pinpoint the source of the problem and identify the responsible parties.

Contamination of Water in a Condominium

APTECH was hired by an insurance company to investigate reports of contamination in the tap water in one unit of a condominium complex. The manifestation of the problem was black stains on clothes that had been sent through the washing machine. Since this condominium unit was the only 40

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one affected in the complex, our investigation focused on the water supply line and internal plumbing. The investigation included a field examination, contaminant sampling, and chemical analysis.

Contamination of Hospital Oxygen Piping

A city hospital noted the presence of contaminants in the filters in the oxygen piping leading to the incubators in the maternity ward. The hospital quickly switched over to their back-up oxygen system. APTECH was hired by an insurance company to find the source of the contamination. A field examination revealed the source to be due to a through-wall penetration caused by external corrosion in an underground copper pipe. This piping was replaced.

Steel Tendon Corrosion

APTECH was hired by a major home builder to investigate the corrosion of steel cables used in a post-tension-reinforced concrete slab design. Our investigation included the use of groundpenetrating radar and electromagnetic techniques for location of suspect tendons. Soil and concrete corrosiveness were established by laboratory analysis. Our investigation concluded the there was no major corrosion problem. Recommendations were made to the builder regarding corrective actions.

Water Tank Corrosion

A domestic water distributor experienced premature corrosion damage on several carbon steel water storage tanks. APTECH was hired by the company to conduct an independent review of the tank corrosion protection system. Our review consisted of examining the design specification and tank inspection results. We concluded that the original coating material which was specified by the designer was inadequate. We recommended alternative coating methods and materials.

Recirculating Hot Water Piping System

A major hospital experienced accelerated corrosion damage in the carbon steel piping of a recirculating hot water heating system. APTECH was retained to determine if the cause of failure was due to pipe manufacturing defects. Our analysis consisted of nondestructive inspection, metallurgical examination of corroded piping, and water chemistry analysis. We suggested that the existing water treatment/corrosion control methods be modified to include on-line corrosion rate monitoring.

Degradation of Condominium Plumbing System

The galvanized piping throughout a condominium plumbing system had experienced premature failure. APTECH was hired by the condominium association to perform a failure analysis for the purpose of establishing the root cause. Our analysis revealed that the failures were due to pipe manufacturing practices.

Solar Water Heater System Failure

APTECH was hired by a solar water heater manufacturer to investigate a corrosion failure problem that was allegedly due to a system design fault. Our work included metallurgical and corrosion engineering analysis, as well as a materials review of the entire heating system. Our conclusion was that the corrosion failure was due to incompatible materials in one of the components supplied by another company and was not associated with the overall system design.

Flood Damage to Steel Supplier

A steel supplier storage yard adjacent to an estuary was subject to frequent flooding. The supplier sued the agency responsible for flood control for damages resulting from corrosion of steel materials. 41

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APTECH was hired by the agency to establish the validity of the damage claim. Our investigation included metallurgical analysis of the corrosion damage, as well as a financial analysis pertaining to the value of damaged material. Our findings, that the corrosion damage greatly exceeded that associated with a worse case flooding, indicated that the material had been subjected to other damage mechanisms such as stagnant water corrosion due to storage conditions.

Condominium Copper Plumbing Failures

A condominium complex suffered extensive failures in a copper pipe plumbing system. The installer of the water distribution system was among a number of parties that were implicated in the copper piping failures. APTECH was retained by the installer to determine the cause of the failures. Our analysis indicated that the corrosion damage was not related to the distribution piping and was associated with water chemistry and/or the copper piping materials.

Leakage in Stainless Steel Solar Collectors

A solar heating system equipment manufacturer was experiencing leakage in an expanded stainless steel collector. They hired APTECH to investigate the corrosion damage. Our investigation determined that the corrosion damage was associated with oxidation contamination resulting from the welding fabrication process in combination with specific domestic water supplies that contain relatively high concentrations of chlorides. We advised the client that the stainless steel alloy should be adequate for all domestic waters, provided that the fabrication oxidation was removed prior to use.

Propeller Shaft Failure

A shaft coupling on a large oceangoing freighter failed in mid-ocean. APTECH was retained to make an unbiased determination of the root cause of the failure. APTECH engineers performed a computerized stress analysis and fracture mechanics analysis of the bolting and coupling arrangement. We concluded that the failure was due to normal wear-and-tear.

Personal Injury

Welding Injury from a Decomposing Rubber Gasket

An experienced welder was injured in a non-witnessed accident by inhaling fumes from a decomposing rubber gasket that was used as a seal. APTECH was asked to reconstruct the incident. From the compounding recipe for the gasket, APTECH identified the likely chemical composition of the various raw materials, activators, antioxidants, pigments, accelerators and vulcanization agents used. APTECH engaged a laboratory to thermally decompose pieces of the gasket under nonoxidizing conditions and to analyze the gases evolved. Gasket heating rates were obtained from a series of transient heat transfer analyses. Using GC/MS analyses, numerous chemical species were identified, such as alkenes, alkynes, cyclic dienes, phenols, thiazoles, aromatics, ketones, alcohols, aldehydes, substituted naphthalenes, amids and amines. Several species were selected for more complex quantitative analyses. APTECH prepared a report of its findings.

Loading Dock Accident

APTECH performed a metallurgical evaluation, stress analysis and on-site exemplar testing (including dynamic testing) to determine the cause of the sudden release of a loading dock dockboard. The design, maintenance, and repair procedures of the dockboard were evaluated.

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Mountain Bicycle Accident

A popular model mountain bicycle was involved in an off-road accident. APTECH determined the cause and sequence of events leading to the fracture of front fork of the subject bicycle. The contributions to the failure of corrosion, prior deformation, and riding loads were evaluated.

Electrical Shock Accident in a Modular Electric Power System

An electrical contractor was injured while he was installing electrical cables for a modular office system. He was subjected to a high-voltage shock while making what turned out to be an incorrect connection. The workers' compensation insurance company asked APTECH to investigate the accident. We found that the connection being made should not have been energized, and that the equipment design, installation procedures, and lack of warning signs all contributed.

Truck Tire Mounting Accident

A service station employee was injured when the truck tire he had just mounted on a wheel exploded during inflation. APTECH's investigation of this accident included nondestructive testing of the tire to look for pre-existing flaws, confirming that the wheel and its lock ring were matched correctly, and reconstructing the sequence of events leading to the injury.

Paper Mill Accident

While operating a machine that manufactures paper, a plant employee's arm was injured when it was caught by an in-running nip point between two large, counter-rotating drums. APTECH was called in by the workers' compensation insurance company to find the root cause of the accident. The investigation focused on the procedures followed by the injured party, and recommendations were made to the plant to modify either the machine or the procedure.

Electric Switchgear Accident

An electrician was knocked down and badly burned when the 2000-amp electrical chassis he was modifying short-circuited. The workers' compensation insurance company hired APTECH to investigate the accident. APTECH's findings indicated that the three-phase bus bars had been bridged by a loose metal component, and that the panel had not been de-energized before the work commenced.

Concrete Mixer Truck Accident

A construction worker was injured while loading bags of dry mix into a truck-mounted concrete mixer. His arm was caught between the charging hopper and the barrel's internal mixing blades. The workers' compensation insurance company asked APTECH to investigate the accident. APTECH's investigation included an assessment of effectiveness of mechanical guards, warning signs, and operator safety training programs.

Racing Boat Accident

During a dragboat racing event, one of the contestant boats lost control as it crossed the finish line at 190 mph. This boat then veered off course, ran ashore, and killed a spectator. APTECH performed a complete root-cause investigation of this event, including metallurgical and stress analyses of the failed steering gear and an analysis of the hydrodynamic forces on the boat hull and supercavitating rudder and propeller. APTECH also performed an extensive risk analysis of the course layout. The failure of the Woodruff key in the steering gear was explained in terms of the extreme forces that existed on the boat's rudder during deceleration after crossing the finish line.

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Aircraft Collision

A light aircraft was destroyed in a mid-air collision with a jet trainer. APTECH was retained by the insurance carrier of the light airplane to reconstruct the accident. We obtained the remnants of the airplane and reassembled them in our laboratory. Measurements of the metal deformation, followed by stress and fracture mechanics analyses, enabled us to identify an impact point on the fuselage of the light plane.

Portable Oxygen System Fire

The gas flow from a portable therapeutic oxygen system suddenly ceased, and an acrid odor was noticed by the patient. APTECH was retained by the product manufacturer to determine the cause of the failure. The components of the system, including a valve, regulator and pressurized oxygen cylinder, were dismantled, examined, and photographed. Carbon steel and brass surfaces showed evidence of exposure to high-temperature, corrosive gases. Also, several rubber seals were missing or damaged. These findings led to the conclusion that a brief, but intense, fire had occurred inside the valve, involving the rubber seal (the fuel) and the pure, high pressure oxygen. Possible sources of the ignition energy included a spark (frictional or static electrical) or adiabatic compression.

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Section 8

CASE SUMMARIES -- FIRES & EXPLOSIONS

Boilers and Power Machinery

Gas-Fired Utility Boiler Explosion

During shutdown, explosions occurred in the furnace and backpass of a 170 MW gas-fired utility boiler. The utility company's insurance carrier retained APTECH to do a third-party investigation of the origin and cause of the incident. The boiler was a 1950s-vintage, Combustion Engineering unit with front-wall mounted burners. The burners did not have flame scanners, so the boiler was operated under the NFPA's manual operation guidelines. APTECH experts examined the operational data and found that alarms for carbon monoxide and combustibles had occurred prior to the explosions. We walked down the entire boiler and documented the damage pattern. The furnace buckstays and the walls of the backpass were bowed outward. The outward deflection of the walls caused the economizer to fall into the hopper below. The superheater screen tubes were severed at the roof. Most of the severed screen tubes were found deflected into the superheater, but one of them fell to the furnace floor. The evidence indicated that there were at least two separate, but temporally closely spaced, explosions ­ one originating in the furnace above the burners and the other in between the superheater and reheater. Metallurgical examinations of the screen tubes showed that they had preexisting hydrogen damage. The examination also showed that the tubes had been severed when the furnace explosion lifted the roof. The reaction forces from the steam jets accounted for their final positions. APTECH determined that the fuel that exploded was raw natural gas from unignited burners. The bottom row of burners had been extinguished when they became too fuel-rich as the fuel, but not the air, was shut off to the upper burners. The unignited burners were not detected due to the absence of flame scanners. APTECH provided an origin and cause report to the client.

Explosion at Solar Energy Plant

APTECH was asked to determine the root cause of an explosion at a solar trough steam-electric power plant. Tanks holding the circulating heat transfer fluid had unexpectedly exploded. APTECH conducted an onsite investigation including interviews with witnesses; and a metallurgical and engineering investigation and analysis using samples and data acquired at the plant. APTECH prepared a report of its findings.

Coal-Fired Utility Boiler Explosion

A 760-megawatt utility boiler (cyclone-fired) in the midwest suffered a severe explosion in the upper furnace. APTECH was retained by in-house counsel of the utility to investigate the cause and origin of the explosion and to quantify the extent of damage to the boiler. The explosion occurred while test-firing western coal; the boiler was designed for midwestern or eastern coal. APTECH made recommendations for the improvement of the boiler control system and identified deficiencies in the boiler furnace enclosure design. The operator evaluated our recommendations and made the necessary upgrades and improvements.

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Pulverized Coal Pipe Fire

A fire broke out in a coal pulverizer in a 110 MW coal-fired power plant. An APTECH power plant engineer was hired by the insurance adjuster to evaluate the cause and origin of the fire. The equipment was thoroughly inspected and photographed. The plant's operation and maintenance personnel were interviewed, and work orders, drawings and other documentation were reviewed on site. We found that a modification to the coal/air piping had been done improperly, which caused the failure of an expansion joint. The resulting jet of pulverized coal caught fire, and this flame ignited common combustibles. Damage to the plant was considerable, and subrogation potential was assessed.

Gas Turbine Fire

A gas turbine was exposed to a fire that was fed by a leak in the lubricating oil supply line. APTECH was retained to evaluate the condition of the turbine rotor with respect to the possible loss of strength and material embrittlement. Our evaluation of the material indicated that the time/temperature fire exposure history would not result in degradation of the rotor's material properties. We concluded that the rotor was not adversely affected by the fire, and recommended that dimensional checks of the rotor be performed.

Steam Turbine Failure and Explosion

A steam turbine in an oil refinery was undergoing a routine trip test following maintenance work. During this test, the turbine broke apart into several pieces causing personnel injury and death. APTECH was retained by the refinery to determine the root cause of the accident. To reconstruct the accident, we examined the layout and components, interviewed plant personnel, inspected operating records and logs, and reviewed safety procedures. APTECH performed metallurgical failure analysis, turbine reconstruction, roto-dynamic and energy calculations to determine the root cause.

Package Firetube Boiler Explosion

An explosion occurred in a package boiler in a downtown office building. There were no injuries and damage was confined to the boiler and plant from the explosion. APTECH was hired to find the cause and origin and to make sure that it did not recur. First, we interviewed witnesses and examined and documented the condition of the as-found boiler. Next, we prepared a "punch list" of recommended repairs and modifications. Finally, we gathered test data when the boiler was brought back on-line. Based on our findings, we presented four possible failure scenarios to the client, including gas supply over-pressure, a fault in the flame detector system, a build-up of unburned fuel, and an overly-rich fuel/air mixture. Modifications to the boiler and its operating procedures were made to prevent a recurrence of this explosion.

Catastrophic Failure of High Energy Power Plant Piping (Mohave Plant)

A 30-inch diameter hot reheat steam pipe, operating at 1000°F and 600 psig, ruptured without warning in a fossil power plant. This accident caused numerous fatalities and major property loss. APTECH was hired by one of the defendants to investigate the failure of the pipe. APTECH performed a detailed stress analysis of the as-built line configuration and evaluated the material properties and the likelihood of creep damage under stresses sustained during normal operation. APTECH also investigated maintenance practices over an extended period at the plant prior to the failure. We concluded that the failure was caused by creep damage in local regions adjacent to the heat affected zone of the long seam weld.

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Downcomer Pipe Exposed to an Oil-Fed Fire

A downcomer pipe in a large electric generating plant was exposed to an oil-fed fire. APTECH evaluated the pipe using wet fluorescent magnetic particle, ultrasonic shear wave, field metallographic, and hardness testing techniques. These tests indicated that the downcomer pipe and connecting welds were satisfactory for continued service.

Transformer Fire in a Utility Power Plant

A fire occurred at the Haynes Station of the Los Angeles Department of Water and Power. The fire started in an output transformer for Unit 1 (230 MW). APTECH was retained to evaluate the effects of the fire on structural components, including a gantry crane that was situated immediately above the fire. Mechanical property characterization tests (hardness, tensile, and Charpy V-notch tests) and temperature estimates (from response of paint and tempering of high strength fasteners) indicated that these components were not adversely affected by the fire. However, our examinations revealed unexpected degradation of the gantry crane from corrosion of its internal structure.

Process Plants

Explosion in a Chemical Blending Vessel Due To Unrecognized Explosion Hazard of Blended Materials

APTECH was retained to investigate the cause of an explosion in a blending vessel in a chemical processing facility. The explosion destroyed the plant and caused fatalities and injuries among the plant workers and first responders. At the time, the vessel was mixing together powdered sodium hydrosulfite, aluminum powder, and potassium carbonate. Several hours before the explosion, the mixture began bubbling and producing heat and hydrogen sulfite fumes. Sodium hydrosulfite is known to react exothermically with water at room temperature. APTECH analyzed the unique explosion chemistry of the mixture of water, sodium hydrosulfite, aluminum, and potassium carbonate. We determined that the aluminum powder acted as a high energy fuel which magnified the explosion energy release by several hundred percent. APTECH provided expert testimony during depositions.

Explosion in a Blending Vessel due to Mechanical Seal Failure

APTECH was retained to investigate the cause of an explosion in a chemical blending vessel in a processing facility in New Jersey. The explosion, which was completely unexpected, destroyed the plant and caused fatalities and injuries among the plant workers. The toxic plume from the ensuing fire injured several firefighters. APTECH's investigation focused on identifying how water might have been introduced into the blender. We determined that the water would have to have been injected into the interior of the powder bulk, and that the built-in agitator bar would have been the water conduit. The agitator's drive shaft had an outboard mechanical seal, which was water-cooled. The carbon-graphite sealing face was examined and found to be worn out. This wear would have allowed the cooling water to leak between the faces. Such a leak would have flowed along the agitator, through the felt packing, and into the middle of the bulk solids. The carbon sealing face had been damaged by particles in the water. APTECH determined that the vessel manufacturer, who advertised that their product could blend a wide variety of chemicals, had incorrectly used a water-cooled seal instead of a dry-running seal. The elimination of the risk of a water leak would have prevented the explosion. APTECH provided expert testimony during depositions.

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Explosion in Ammonium Nitrate Fertilizer Manufacturing Plant

In 1994, a massive explosion occurred in a fertilizer manufacturing plant in Iowa. APTECH was retained by outside counsel for the plant's insurance carriers to determine the origin and cause of an explosion event. We were called in early to inspect and analyze the thousands of metal fragments collected at the site that originally came from explosion-damaged vessels, piping, pumps, and valves. We determined that the explosion was a detonation and that it originated in a large vessel called the nitric acid­ammonium nitrate neutralizer. We worked extensively with consultants from several other organizations to reconstruct the conditions leading up to the explosion. We performed simulation tests of various process flow streams during the neutralizer shutdown and stand by conditions. Through laboratory and field tests, we quantified the thermal decomposition and explosion characteristics of the combination of ammonium nitrate, nitric acid, and reactive metals (i.e., titanium and aluminum). From this work, we determined that the explosion resulted from a thermal cook-off process that occurred in the neutralizer vessel while it was off-line. We performed a detailed evaluation of the neutralizer design and concluded that design defects, both in mechanical configuration and in materials of construction, were the root causes of the accident. APTECH provided expert reports and deposition testimony.

Fire and Explosions at an Ammonium Perchlorate Plant (PEPCON)

A fire of unknown origin broke out at a large ammonium perchlorate manufacturing plant. The fire quickly got out of control, and eventually led to the detonation of thousands of pounds of the chemical stored at the site. The detonation demolished the plant and its shock wave caused significant property damage. APTECH was hired to investigate the accident. Our work included examining and documenting the accident site, testing subscale chemical containers, reconstructing and locating the explosion sequence, and analyzing the metallurgical condition of an underground natural gas pipeline.

Heat Exchanger Failure in an Olefin Plant

During start-up of a olefin plant, a large heat exchanger shell ruptured catastrophically causing extensive fire damage to the plant and injury to plant personnel. APTECH performed a detailed root cause analysis of the shell failure scenario, including modeling of the two-phase working fluid thermodynamic transients, convection, and conduction heat transfer in the shell, and stress and fracture mechanics analyses of the shell/tubesheet weld where the brittle fracture originated. An insurance coverage dispute developed, and our root cause analysis was vigorously challenged by an opposing team of experts. This dispute was resolved in arbitration proceedings, during which our engineers testified for 40 days. The arbitration panel voted unanimously in favor of APTECH's determination of the root cause of the accident.

Hydrogen Explosion in Steel Plant Coker Area

Four workers were performing routine maintenance and cleaning inside an off-line ammonia scrubber vessel. Suddenly, an explosion occurred and all four workers were killed instantly. APTECH was brought in to perform a detailed review of all process variables preceding the explosion, in order to determine the root cause of the explosion. It had been determined that a coke oven gas valve was leaking, but blanking of valves and purging of the vessel had been performed so the explosive gas accumulation was a mystery. APTECH performed detailed analyses to determine the patterns and magnitudes of the gas and air flows in the vessel and the eventual stratification of explosive gas at the vessel top. APTECH also performed detailed stress analysis of several deformed valve blanks to determine the blast over-pressure resulting from the explosion.

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Explosion in an Aluminum Annealing Molten Salt Tank

A molten salt tank exploded while being brought on-line from cold conditions. Three people were killed and extensive structural damage to the facility resulted. APTECH was asked to assess alternate theories for the root cause of the explosion, including both local and global overheating of the salt bath. Our investigation included an analysis of the radiation and convection heat transfer in the furnace and salt bath and an analysis of various chemical reactions in the salt bath proposed as the root cause of the final detonation.

Sodium Hydrosulfite Container Fire

A steel drum containing sodium hydrosulfite ignited and generated a sulfur dioxide plume which extended over many blocks of an industrial/residential area of Berkeley (California). Sodium hydrosulfite is a solid granular material used in the dry cleaning industry and is highly reactive with water and air. APTECH was hired to evaluate this event from a technical point of view, to determine whether a "fire" had occurred in the usual sense of the word. This was relevant to the question of insurance coverage. We performed a detailed investigation of the chemistry of sodium hydrosulfite decomposition and ignition, including combustion, heat transfer, and plume analyses.

Urea Autoclave Vessel Explosion

A high-pressure urea reactor vessel in a fertilizer plant exploded with tremendous energy release, causing extensive damage to the plant and hurling pieces of the vessel up to a quarter-mile away. APTECH was part of a team of investigators retained to determine the root cause of this accident. The vessel was 30 years old and had a laminated wall design with a stainless steel liner. We reviewed and analyzed this vessel's lengthy and complicated maintenance and alteration history. The origin of the vessel fragmentation was found to be a local area where extensive corrosion had occurred through several of the wall lamina, thus substantially wakening the vessel in this area.

Natural Gas Compressor Station Fire

A fire broke out in a gas turbine-driven natural gas compressor, causing damage to the unit and to adjacent equipment. APTECH was hired to determine the root cause of the fire and to itemize the extent of damage produced by this fire. Our evaluation involved site inspections, interviews with site personnel, field metallurgical testing (e.g., metallurgical replication, hardness measurements, etc.), reviewing the lubrication system designs and fire suppression, and a nondestructive laboratory failure investigation of a fractured lube oil line. We determined that an unnoticed oil line vibration caused fatigue at a fitting and the oil line ruptured. The oil impinging on the hot section of the gas turbine ignited and caused the fire. APTECH provided expert opinions regarding the cause of the fire, the extent of subsequent damage, and the repair cost estimates.

Natural Gas Filter-Separator Vessel Failure and Explosion

The closure of a 40-inch diameter filter separator (a pressure vessel used for filtering natural gas) failed and resulted in an estimated $25 million in damages. The 5000 pound steel head of the vessel was shot approximately 1/4 mile and the vessel was launched 30 feet in the opposite direction. Much of the surrounding equipment in the plant was destroyed by a fireball that was created when the escaping gas was ignited. No one was present when the failure occurred. If it had occurred on the previous night, up to 20 people may have been killed. APTECH was contracted by the manufacturer's representative to determine the cause of the failure. Our on site activities included visual surveying and analysis, photo documentation, video documentation, and dimensional analysis of the wreckage. During the site investigation, it was 49

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determined that the operator of the vessel had used oversized o-rings during an overhaul of the vessel just hours prior to the accident. Analysis in our laboratory included metallurgical evaluations, finite element stress analysis, scanning electron microscopy of components involved in the accident, and load testing of exemplar components of the closure. The exemplars were fitted with strain gages. Data was collected by means of a computerized data acquisition system. Subsequently, pressure testing was performed on a near-full-scale mockup of the entire vessel. The mock-up also was fitted with strain gages at strategic locations. After performing the tests with both standard-sized and oversized o-rings, it was determined that the stress at critical locations was up to five times higher with the oversized o-rings.

Gas Explosion and Fire in an Industrial Building

An investigation and analysis of an explosion which occurred in the attic space of a newly constructed industrial building was performed. The physical evidence indicated that the accident resulted from ignition of an accumulation of natural gas. The gas was being purged through a new gas line being attached to a gas heating furnace. Visual examination, interviews with plant personnel, review of accident reports, leak testing of the gas piping, and evaluation of ventilation requirements were included in APTECH's evaluation of this accident.

Petrochemical Refineries

Refinery Delayed Coker Accident

A refinery contracted with skilled concrete workers for the repair of concrete structures supporting delayed coking vessels. The refinery staff believed that repairs could be safely made while the unit was operating. If the coker had to be shut down to make these repairs, the refinery would have to reduce production to accommodate the unavailability of the unit. While the crews were working on the unit, a freak accident caused superheated steam to be released, severely scalding several workers. APTECH was retained by a law firm representing these workers. We were asked to investigate the prudency of assigning repair crews to work on an operating unit of this type, to survey the experience of other refineries regarding safe work practices, to develop accident statistics, and to determine if any mechanical failures were involved.

Refinery Asphalt Pump Failure and Fire

A small refinery that produced asphalt and ink oil experienced a serious fire under the atmospheric and vacuum bottoms tower. No injuries were suffered, but the fire caused extensive damage to the plant and resulted in one year of business interruption. An investigation by the refinery pointed toward the accidental ignition of light oil that was spraying out from a leaking pump shaft sealing device. A series of unexplained pump seizures was also included in the accident scenario. Working for the refinery, APTECH analyzed the design and materials of the pump shaft sealing system (metal bellows, dynamic type), and evaluated the fitness-for-purpose of the type of asphalt pump that was supplied by the manufacturer.

Refinery Coker Unit Fire Caused by Ruptured Piping

A fire broke out under a coker unit in a large oil shale processing plant. Liquid hydrocarbons feeding the fire eventually caused the formation of a pool fire that spread over 20,000 ft2 of the premises. The plant's pressure vessels and piping were extensively damaged due to overheating. APTECH was hired to find the cause and origin of the fire. The field inspection revealed that a slurry recycle pipe had been the first to rupture and spill its combustible contents. Metallurgical testing of the ruptured 50

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pipe showed that the wall thickness of the pipe had been greatly reduced by corrosive attack from the slurry. The rupture occurred at the thinnest part of the pipe wall.

Coking and Fire in a Refinery Hydroprocessing Vessel

A pipe rupture in an operating hydroprocessing unit in a refinery caused a fire and extensive coking within several vessels (reactors, columns, etc.). The refinery carried separate fire and boiler/machinery coverages. As part of the ensuing arbitration, the insurers were interested in the extent of coking (and time to clean out the coke from the vessels) if there had been no fire. This information would permit proper allocation of a portion of the business interruption claim. APTECH was retained by one group of insurers to independently estimate the downtime due to coking assuming no fire had ensued. We delivered several time-lines of event sequences, contacted operating and industrial maintenance companies for relevant experience, and developed independent estimates of worker productivity when mining coke inside of confined spaces.

Refinery Maintenance Accident and Hydrogen Fire

A refinery piping assembly that was being dismantled by a contractor suddenly released flammable gases. The gases subsequently ignited and the contractor suffered burn injuries. APTECH was retained by the refinery's law firm to determine the cause and origin of the fire. To reconstruct the accident, we examined the site of the fire, interviewed plant personnel, inspected the plant's operating logs and safety procedures, and reviewed witnesses' statements and deposition transcripts. Key components of the piping system were examined, photographed, and pressure-tested (hydrostatistically) to document their current condition.

Refinery Piping Erosion Failure and Fire

In this project, APTECH evaluated the root cause of a pipe failure and ensuing fire at a refinery in Southern California. The oil/catalyst slurry at high temperature that is used for heat recovery boilers is an erosive mixture for normal carbon steel piping in refinery plants. In-plant systems are developed to monitor erosion as it occurs using various nondestructive testing techniques. In this particular incident, the FCC main column Bottoms slurry piping eroded to such an extent that the flange connecting the piping to the vessel bottom failed catastrophically. The ensuing fire caused significant plant damage and personnel injuries. APTECH investigated the inspection procedures, the materials involved, and the process parameters that led to the accident.

Refinery Process Heater Fire

A rupture of a fired heater piping connection containing a thermally stabilized silicone polymer fluid led to a fire and extensive secondary damage to other furnace components. APTECH performed a detailed root cause evaluation of the ruptured tube and a suitability-for-service evaluation of the remaining furnace components. This evaluation involved interviews with plant personnel, field evaluation of the critical components in the furnace, review of operation and maintenance manuals and records, detailed metallurgical evaluations of select components, and engineering life assessments. A technical report and expert opinions were presented to all concerned parties.

Oil Production

Oil Well Drill Rig Fire

An oil well drilling operation was conducting a routine fracture stimulation process when a truckmounted oil pump/storage tank caught fire. The fire spread and injured a worker, destroyed valuable drilling equipment, and eventually ignited the oil well itself. APTECH was retained by one of the 51

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defendants to determine the original ignition source. Our investigation and analysis revealed many alternative sources of ignition, including a spark from an electrical short-circuit, a frictional spark, a static electrical discharge, and flames from a Diesel engine exhaust pipe.

Oil Well Abandonment Accident and Fire

While a field crew was "killing" an old oil well, a massive volume of natural gas was suddenly and unexpectedly released from the well head piping. Shortly thereafter, the subsequent gas/air mixture was ignited, resulting in a brief, but extremely intense, fireball. One person was killed, several more were severely burned and the nearby equipment was totaled. The oil company hired APTECH to assist its staff engineers with a cause and origin evaluation. We photographed and diagrammed the accident site and piping, provided immediate advice on site preservation (to avoid future claims of evidence spoilation) and performed a detailed examination of the pipe fittings and potential gas release points. Our reconstruction of the events leading up to this accident was aided by an engineering mechanics analysis of the forces applied to the piping by the crew and their hand tools.

Commercial and Residential

Underground Migration and Explosion of Propane Gas

On a November morning in 1996, a massive explosion occurred in a commercial building in a busy shopping district in San Juan, Puerto Rico. The explosion caused 33 fatalities and numerous injuries. The building was destroyed and adjacent structures and vehicles were also damaged. APTECH was retained by the Plaintiffs' Steering Committee to conduct an independent engineering investigation of origin and cause of the explosion. Explosion and structural analyses by APTECH established that the origin of the explosion was in the basement of the building. This is consistent with the fuel that exploded being heavier-than-air propane, which would have settled into the basement. Soil testing revealed the presence of residual propane gas in the soil and groundwater in and around the explosion site over 1 year after the explosion. Also, the soil at the site was found to be sufficiently porous to allow gas to migrate through it. Finally, during a field test at the site, we established that Argon gas introduced into the soil near the leak site readily migrated through the soil toward the building. We concluded that the origin of the explosion was in the building basement, the fuel for the explosion was propane, the source of the propane was leaking underground pipes, and that the propane migrated through the soil from the leaks to the basement.

Agricultural Chemical Warehouse Fire

A fire in an agricultural chemicals warehouse destroyed the building and its contents. APTECH was retained by the building owner's law firm to find the cause and origin of the fire. Previous investigators, including the fire department, had narrowed down the source of the fire to a pickup truck that was parked inside the warehouse. We reviewed the witnesses' deposition transcripts, inspected the exemplars of the pickup truck (because the original truck had been destroyed), and examined the truck manufacturer's drawings and specifications. Our investigation indicated that an electrical wiring harness had short-circuited and ignited a nearby plastic fuel line.

Abandoned Gas Main Piping Explosion

A large explosion occurred under a busy city street, creating a 25-foot crater. The explosion originated in a large-diameter, natural gas main pipe buried under the street. Fortunately, there were no injuries or significant property damage. The gas utility company hired APTECH to find the cause of the explosion and to suggest ways of preventing future incidents. We discovered that, some months earlier, the pipe had been plugged and abandoned by the utility. Our investigation focused 52

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on identifying the explosive gas mixture, the gas source, and the ignition source. On-site engineering activities included site photo documentation, crew interviews, residual gas sampling, and soil and metallurgical sampling. Subsequent analysis led to an explanation of the explosion event. We also recommended that changes be made in piping configuration management, abandonment procedures and crew safety guidelines.

Ammonia Cylinder Failure

A pressurized cylinder containing anhydrous ammonia ruptured and exploded inside a blueprint plant. The cylinder broke free from its wall anchors and launched itself into an occupied room. Injuries and property damage were caused by the ricocheting cylinder and by the release of ammonia gas. APTECH was hired by one of the defendants to determine the root cause of the failure of the cylinder. Metallurgical examinations led to the conclusion that the rupture initiated at a small fatigue crack on the inside surface. The fatigue crack had formed slowly over the years due to pressure cycling. The cylinder was judged to have been in service beyond its safe operating lifetime.

Ammonia Tank Car Explosion

A transportable road tank car came uncoupled from its tractor, crashed onto a lower level freeway, and exploded. It caused significant personal injury and local damage. APTECH performed metallurgical and fracture analyses to establish the root cause of the tank car's structure failure that led to the crash and explosion.

Bakery Explosion

An explosion and fire occurred in the basement of a bakery in Fresno (California), causing extensive damage to the contents in storage. Leaks were discovered at several locations in a four-inch gas main under the streets adjacent to the bakery. APTECH was hired to perform a gas migration and explosion analysis. Through our analysis, we were able to conclude which gas pipe leak was the cause for the amount of gas which accumulated in the basement and exploded causing the observed damage.

Shopping Center Fire

A fire broke out in a small shopping center in a commercial district of a large city. The fire began in the ceiling of a fast-food restaurant and spread to the adjacent shops. Considerable damage was done, and faulty electrical wiring was blamed. APTECH was retained by the electrical subcontractor to investigate this possibility. To reconstruct this accident, we examined architectural drawings and electrical diagrams, reviewed a large quantity of documents and deposition transcripts, and evaluated the design of the electrical system. Also, other potential causes and original of the fire were investigated.

Restaurant Grill and Ventilation System Fire

Early in the morning in a large restaurant, a fire started inside the kitchen's ventilation ducting system. The automatic fire extinguishers were overwhelmed, and severe damage was done to the roof before the fire was knocked down. APTECH was retained to evaluate the origin of the fire. The circumstances of the incident included a grease fire flare-up on the grill during adjustment of the gas burner, excessive room ventilation rates, and improperly cleaned ducting and grease traps.

Gasoline Tank Farm Explosion and Fire

Gasoline was being delivered by a tanker truck to one of many above-ground storage vessels in a commercial tank farm. During the delivery, an explosion of a cloud of gasoline vapors occurred near 53

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the storage vessel. Besides destroying several buildings, the explosion breached the piping system. This led to an extensive release of gasoline, which caught fire and contaminated the soil. APTECH was hired by the plant's owner to determine how the explosion caused the failure of the piping system. Our metallurgical examination and fluid mechanics calculations indicated that the gasoline vapor explosion had severely distorted a swing check valve. This event blew off a threaded plug in the body of the valve. The absence of the plug allowed the free flow of gasoline. The gasoline continued to feed the fire and contaminate the soil until the pump was shut down.

Restaurant Fire

An after-hours fire occurred in a fast-food restaurant. The fire department traced the fire's origin to a store room in the rear of the building. An independent fire investigator theorized that arcing from a faulty electric light switch ignited common combustibles. APTECH was hired by the electrical subcontractor to perform an engineering evaluation of the electric switch. Our examinations led to the conclusion that the switch could have been damaged as the result of the fire rather than having been the fire cause.

Evaluation of Floor Furnace in Fire Damaged House

APTECH was retained to evaluate a gravity-type, gas-fired floor furnace in a fire-damaged house. We photographed the condition of the furnace and its piping and wiring as they were found in the crawlspace under the living room floor. The furnace then was removed and taken to our lab. Upon further examination, the furnace did not appear to have malfunctioned. Subsequently, the source of the fire was determined to have been a pile of newspapers and a couch that had been placed on the floor over the furnace's warm air register.

Residential Explosion and Fire

In the middle of the night, a multi-story residence in South San Francisco exploded and burned to the ground. APTECH was hired by the local gas utility to come to the site and conduct a root-cause investigation. An immediate site inspection was required because the local fire department authorities required that the smoldering debris be removed immediately. In this way, the fire could be completely extinguished and any threat to adjacent structures eliminated. APTECH was on site immediately and, working with other investigators, quickly determined that the gas pipeline into the building had been hack-sawed completely through at a location upstream of the regulator. Deliberate arson was the obvious cause and was eventually traced to the building's owner.

Apartment Gas Explosion

An apartment unit in downtown San Francisco exploded and burned, resulting in fatalities and significant property damage. Natural gas was suspected as having been involved. Working with the local gas utility's claims people, APTECH investigated the possible sources and migration paths of the gas. The evidence and our evaluations indicated that the room had filled with gas from an unignited range/oven burner that had been deliberately opened by one of the occupants. A combustible mixture of gas and air eventually developed. Subsequently, when the front door was opened by the other resident, the mixture flowed over to an ignition source and exploded.

Swimming Pool Water Heater Fire

A fire originated in the equipment room of a 24-unit apartment building causing extensive fire and smoke damage to the structure and the tenants' possessions. APTECH traced the origin of the fire to a malfunctioning swimming pool water heater. The heater was disassembled in APTECH's laboratory, and a detailed inspection was performed on the burners, burner controls, and heat 54

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exchanger fire side and water side. The root cause of the heater malfunction was identified, and an article explaining how to avoid the situation was prepared for the equipment owner's group.

Explosion in Three-Story Brick Building

A late-night explosion in a three-story brick building in San Francisco (California) totally destroyed the building and killed three nearby pedestrians. Within hours, APTECH was brought in by the local gas utility company to survey the scene and collect crucial evidence. The gas company wanted to determine if gas was involved and, if so, the location of the leak. The building was suspected of housing a drug-manufacturing laboratory, so the Federal Bureau of Alcohol, Tobacco, and Firearms was also involved, as well as the San Francisco Fire Department. We surveyed the effects of the blast wave on neighboring structures. We also examined gas piping, appliances and the gas meter inside the building, and the gas service piping outside the building. Finally, we performed a preliminary analysis of the ignition and explosion event.

Natural Gas Migration and Explosion in an Apartment Building

In this project, APTECH was hired by the local natural gas utility company to evaluate the origin and cause of a gas explosion in a downtown apartment building. APTECH visited the accident scene shortly after it had occurred and performed analyses to investigate the following: (1) the likelihood of a gas leak from nearby regulators; (2) the likelihood of gas migration across the road to the location of the apartment building; and (3) the significance of mechanical tool marks on gas piping and gas fittings. APTECH's analysis eliminated all of the component failure events that could reasonably be responsible for the gas explosion. It was later concluded that the root cause of this explosion was due to human intervention.

Residential Gas Range Fire

The kitchen in an apartment unit suffered heavy damage from a fire that originated at the gas-fired range. The resident blamed a gas leak from one of the burner control valves. APTECH was retained by the insurance carrier's fire investigator to evaluate the condition and operability of the range. We examined and photographed the fire-damaged range in our lab, and reviewed the manufacturer's specifications. Pressure-testing of the gas valves and tubing revealed no leaks, and the valves operated normally. These conclusions pointed toward a simple grease fire as being the cause of the kitchen fire.

Automobile Fires

APTECH has investigated several automobile accidents that have involved fires and explosions, including single- and multi-car collisions and component failures. Our activities have included accident site documentation, evidence preservation, witness interviews, component failure analysis, and accident reconstruction.

Mobile Home Fire

A mobile home in an isolated location caught fire during the night and one occupant was fatally injured. APTECH was brought in by the insurance company for one of the potential defendants to determine the cause and origin of the fire. The investigation included a review of fire department accident reports and photographs, interviews of knowledgeable parties, and an examination of the accident site. Potential fire causes included non-code gas piping, a malfunctioning appliance, and an improperly discarded cigarette.

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Elevator Fire

A three-alarm fire broke out in a 14-story, senior citizen apartment building. The fire caused several fatalities and significant property damage. The source of the fire was traced to one of the passenger elevators. APTECH was hired by the attorney for one of the defendants, the elevator maintenance company, to find the cause and origin of the fire. The plaintiff's expert witness had developed a seemingly logical theory that involved the lubricant tubing (installed by the defendant) having acted like a fuse to spread the fire from the machine room, through the walls, and into the elevator shaft (hoistway). Experiments designed and conducted by APTECH cast doubt on this theory. We demonstrated that a flame attached to the tubing would have been extinguished by the wall's insulation batting before it passed through to the hoistway.

Evaluation of Postulated Propane Explosion

An evaluation was performed to determine the effects of an explosion resulting from the postulated rupture of a propane line. Four types of analyses were performed: Thermal-hydraulic Diffusion Structural Probabilistic The thermal-hydraulic analyses determined the rate and amount of propane gas that would evolve from a postulated line rupture. The analysis considered line design, operating conditions, controls, and operator actions. A transient blowdown analysis was performed to determine a mass release time history. The diffusion analysis determined the size and combustible content of the vapor cloud as a function of distance from the break for various atmospheric conditions. The structural analysis determined the conditions required to cause unacceptable structural damage to the facility of concern. The analysis determined the energy from various size vapor clouds and their effects on the structure based on detonations occurring at varying distances from the structure. The probabilistic analyses considered the following probabilities in determining whether an unacceptable explosion could occur: Pipe rupture occurrence Explosion of vapor cloud Wind direction Wind velocity - The vapor cloud would only be stable enough to remain as an explosive moisture far enough away from the break for limited wind velocities. Atmospheric stability Delay in ignition - The ignition had to be delayed until the vapor cloud was in close proximity to the target structure. This analysis considered available ignition sources, as well as historic data on proximity of ignitions to gas releases.

Risk Management and Prevention Program

For a major supplier of magnetic media, APTECH performed a formal Risk Management and Prevention Program (RMPP) for two inorganic acids as requested by the County government. The public disclosure report documented the site location; equipment and operations history; safety, audit, and inspection procedures; emergency response plans; and actions recommended as a result

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of a HAZOPS study. As a part of the RMPP, APTECH also prepared process flow diagrams, conducted a seismic walkdown, prepared a HAZOP study, and prepared an off-site consequence analysis for several worst-case chemical release scenarios.

Life Assessment for Canadian Refinery

For a major Canadian refiner, APTECH conducted a life assessment study for major classes of equipment, such as columns, pressure vessels, heat exchangers, fired heaters, compressors, tanks, and piping. Over 200 pieces of equipment were evaluated. The majority of this equipment had been in continuous operation for about one design lifetime. Major degradation modes evaluated included creep rupture, stress rupture, corrosion, stress corrosion cracking, high temperature hydrogen attack, wet H2S cracking, and fires and explosions. APTECH identified those pieces of equipment with limited remaining life and for which the client's current maintenance program did not make adequate provisions. Further, utilizing the results of prior risk assessments conducted for the facility, APTECH identified a list of unusually critical equipment which, upon failure, would result in a loss of production of six months or more.

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Section 9

CASE SUMMARIES -- CONSTRUCTION

Evaluation and Remediation of Weld Cracking in Wide Flange Column Connections

A fabricator/erector initially contracted APTECH to determine the disposition and remediation of cracked wide flange column webs. Following a few site visits and meetings, a remediation plan was implemented which comprised of hole drilling at the continuity plate web weld terminations (for currently fabricated columns) and use of a larger cope for new column fabrication. Subsequently, APTECH was contracted by the fabricator's legal counsel to determine the root cause(s) of the column web cracking. Using finite element modeling and mechanical property testing, APTECH's investigation showed that the most significant causes of cracking were related to: 1) a detail design that resulted in excessive restraint and constraint; 2) a detail design that required a complete penetration weld to join the continuity plate-to-column web tee joint; and 3) column steel with highly variable and location-dependent notch toughness. APTECH's technical support and expert witness testimony lead to resolution of this issue via mediation.

Structural Steel/Weld Quality Audit

As the result of concerns expressed by the building's owner, APTECH performed a weld quality audit on the structural steel work. This project addressed two concerns: 1) the quality of the structural steel work; and 2) whether or not the quality concerns had impacted the structural integrity of the steel work. AWS-certified weld inspectors performed a sampling inspection which found, not unexpectedly, numerous deviations and nonconformances (e.g.; cracks, linear indications, lack of fusion, cracked tack welds) from AWS D1.1. APTECH then developed a generic fitness-for-service evaluation to disposition nonconformances which may be present in the structure but not part of the inspection program. These evaluations were based on analyses methods to determine the likelihood of failure under the design loading conditions. While minimizing construction delays and unnecessary repairs, this inspection program and evaluation showed with a high degree of confidence that the structure had sufficient safety margins to tolerate the nonconformances during severe design basis seismic events. APTECH was also retained by counsel for the building owner to facilitate the resolution of construction dispute issues. APTECH's technical support, in collaboration with experts in construction management, lead to the resolution of several key issues via arbitration. APTECH is also providing technical support and expert testimony for additional disputes.

Fitness-For Service of Long Span Girders

A multi-story building was to be constructed on top of an existing subterranean ballroom. Building construction was delayed due to differing opinions among various parties concerning remediation of the ballroom's very large, built-up, long-span steel girders. These girders came under scrutiny for they contained splice joints welded with flux cored electrodes. APTECH used a fitness-for-service approach to confirm the fracture resistance of the existing steel work. The fracture resistance was evaluated using inspection records, design load conditions, and material properties. APTECH's evaluation showed that the existing structure had sufficient fracture resistance to support the new

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structure. This rigorous approach, employing sound, well-established engineering principles, lead to all parties agreeing to proceed with construction of the new building.

Assessment of Earthquake Damage

A hospital in Los Angeles was welded using a high deposition rate flux-cored electrode. The Northridge earthquake occurred during the final months of erection of the structural steel frame. Following the earthquake, some of the welds at the moment resisting connections exhibited cracks. A dispute ensued which centered around the confidence in the existing, uncracked welds. APTECH was contracted by the erector to address the inspection, welding workmanship, and design issues. APTECH proposed a fitness-for service analysis as a cost effective approach in regaining the confidence in these welds which had existed prior to the earthquake. This case is pending trial.

Weld Procedure Review & Fitness-For-Service Analysis of Brine Pipeline

A cement-lined, brine carrying piping system was proving difficult to weld, especially the weld root pass. APTECH worked with this government client to develop a welding procedure specification (WPS) that would minimize weld root discontinuities and, in parallel performed fracture mechanics calculations to provide the client a flaw acceptance criteria which removed unneeded conservatism in the existing workmanship standards.

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