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PRECISION BEARINGS

For Machine Tool Applications

A Quick Reference Guide From NSK Corporation

NSK offers a wide variety of machine tool bearings to satisfy various needs. Typical bearings and applications include: ANGULAR CONTACT BALL BEARING BALL SCREW SUPPORT BEARING (TAC) DOUBLE ROW CYLINDRICAL ROLLER BEARING (NN)

Typical Applications Include: Main Spindles of: · Boring Machines · Machining Centers · Grinding Machines · NC Lathes · · · ·

Typical Applications Include: Machining Centers NC Lathes Linear Positioners NC Milling Machines

Typical Applications Include: Main Spindles of: · Boring Machines · Machining Centers · NC Lathes · Precision Spindle Dies

ENGINEERING DATA FOR NSK MACHINE TOOL BEARINGS: FITTING OF BEARINGS

FITS ON SHAFTS

Bearing Type Shaft O.D. over incl. 10 18 50 80 120 180 18 50 80 120 180 250 Shaft O.D. minimum -0.003 -0.004 -0.005 -0.003 -0.004 -0.005

2

1

Tolerance (mm) maximum 0 0 0 0.003 0.004 0.005

Target Interference (mm) minimum maximum 0 0 0 0 0 0 0.002 T 0.0025 T 0.003 T 0.004 T 0.004 T 0.005 T

2,5

Main Spindle Bearings

3

Angular Contact Thrust Ball Bearing for Ball Screw Support

10 18 30 50 80

18 30 50 80 120

-0.008 -0.009 -0.011 -0.013 -0.015

1

0 0 0 0 0

­ ­ ­ ­ ­

­ ­ ­ ­ ­

PRECISION CLASS BEARING COMPARISONS

The AFBMA tolerance classes correspond in every respect to the classes of precisions adopted by the International Organization for Standardization (ISO 492). These classes and the NSK accuracy codes correspond in the following fashion:

AFBMA ABEC 1 ABEC 3 ABEC 5 ABEC 7 ABEC 9 ISO Normal Class Class 6 Class 5 Class 4 Class 2 NSK (ISO) P0 P6 P5 P4 P2 NSK (ABEC) PA1 PA3 PA5 PA7 PA9

FITS ON HOUSING

Housing Bore over incl. Angular Contact Ball Bearing (Fixed side) Angular Contact Ball Bearing (Free side) Cylindrical Roller Bearing

4

Housing Bore minimum -0.002 -0.0025 -0.003 -0.004 -0.005 0 0 0 0 0 -0.006 -0.007 -0.008 -0.009 -0.011 ­ ­ 0 0 0

2

Tolerance (mm) maximum -0.002 -0.0025 -0.003 -0.004 -0.005 -0.004 -0.005 -0.006 -0.008 -0.010 0 0 0 0 0 ­ ­ 0.016 0.019 0.022

Target Interference (mm) minimum maximum 0.002 0.002 0.003 0.003 0.005 0.006 0.006 0.009 0.009 0.015 0.002 0.002 0.002 0.002 0.002 ­ ­ ­ ­ ­ L L L L L L L L L L L L L L L 0.006 L 0.006 L 0.008 L 0.008 L 0.010 L 0.011 L 0.011 L 0.015 L 0.015 L 0.022 L 0.002 T 0.002 T 0.002 T 0.002 T 0.002 T ­ ­ ­ ­ ­

2,5

Angular Contact Thrust Ball Bearing for Ball Screw Support

18 50 80 120 180 18 50 80 120 180 18 50 80 120 180 10 18 30 50 80

50 80 120 180 250 50 80 120 180 250 50 80 120 180 250 18 30 50 80 120

It should be emphasized that the above equivalency chart is provided for reference only. Specific details regarding accuracy requirements for special applications should be addressed by NSK engineering on an individual basis.

1. The "fits" data above are general recommendations for machine tool spindles operating under normal conditions (inner ring rotation), and for dmn values less than 500,000. Where dmn={[ (Bearing ID + OD)/2]*RPM} For high-speeds, high loads, or outer ring rotation, consult NSK for fit recommendations. 2. Use "Target" Interference when the bearings can be matched to the shaft or housing. Otherwise use Shaft OD and Housing Bore min. & max. for random matching. 3. Applies to Angular contact ball bearings: 70xx, 79xx, 72xx, xxBNC10, xxBNC19; Angular contact thrust bearings: BA, BT, TAC; Cylindrical roller bearings: N10xx, NN30xx, NN39xx. 4. The initial radial clearance for cylindrical roller bearings CC1, CC2, etc. should be selected so the proper mounted radial clearance is obtained; contact NSK for assistance. 5. T=Interference or tight fit; L=Clearance or loose fit.

LUBRICATION

Lubricating Methods Advantages · Low Cost · Limitation of temperature rise is possible · Simple spindle structure · Since new oil is always fed, no fear of oil deterioration · Dust and cutting fluid cannot easily enter Disadvantages · If packed grease deteriorates, seizure may occur · May allow penetration of dust or cutting fluid · Pollution of environment · Oil supply quantity varies depending on the oil viscosity and temperature, so control of a small flow rate is difficult · It is difficult to confirm that oil is actually fed · Frictional loss is big · Since oil leaks, it is difficult to use for vertical spindles · Cost is high · Cost is rather high · Confirmation of whether oil is actually fed to bearings is difficult

Grease lubrication

Oil mist lubrication

Jet lubrication

· Since the oil flow rate is high, dust and cutting fluid cannot enter and seizure hardly ever occurs · Because of cooling by oil, the bearing temperature can be controlled to some degree · Since oil quantity control is possible, the optimum quantity of oil is fed and heat-generation is low · Besides little heat-generation, there is a cooling effect of the air, so the temperature rise is low · Since new oil is always fed, no fear of oil deterioration · Dust, cutting fluid cannot easily enter · Environmental pollution by mist is slight

Oil-air lubrication

RECOMMENDED GREASE VOLUMES

Units:cm3/brg

REMARKS: Double-row angular contact thrust ball bearings [ ]TACC20D or [ ]TAC29D should be packed with the same volume as double-row cylindrical roller bearings NN30 which are mounted on the shaft together with [ ]TAC20D or [ ]TAC29D. Based on NSK's experience, NSK recommends packing an amount of grease equal to only 10% to 15% of the free internal space inside bearings. This is sufficient for proper lubrication and reduces the time required for running in for most applications. For sizes not listed, contact NSK Engineering Department. For most high-speed bearings, NSK recommends using grease with synthetic oil in the case of ball bearings. Mineral oil is recommended in the case of roller bearings.

FOR

MACHINE TOOL SPINDLES BEARINGS

Single-row N10XX 1.1 1.5 1.6 1.6 2.4 2.5 3.5 3.7 4.5 4.7 4.9 5.9 7.5 8.4 12.9 14.0 -- -- -- High-speed angular contact Angular contact ball bearings thrust ball bearings BNC BNC BA & BT 70 72 79 10 19 1.2 1.7 1.8 1.9 2.8 2.9 3.8 4.0 5.5 5.7 6.1 7.6 9.1 9.8 15.0 17.0 22.0 26.0 33.0 1.6 2.4 2.6 2.6 3.6 3.6 5.1 5.3 6.6 6.8 7.2 9.0 12.0 12.0 18.0 20.0 25.0 34.0 42.0 3.0 3.9 4.8 5.7 6.5 7.0 8.7 11.0 13.0 16.0 19.0 23.0 27.0 31.0 34.0 42.0 53.0 63.0 82.0 0.9 1.1 1.2 1.3 2.1 2.3 2.4 3.5 3.6 3.6 4.9 5.1 5.2 7.9 9.0 10.0 14.0 16.0 17.0 1.2 1.7 1.8 1.9 2.8 2.9 3.8 4.0 5.5 5.7 6.1 7.6 9.1 9.8 15.0 17.0 22.0 26.0 33.0 0.8 0.9 1.0 1.0 1.5 1.7 1.8 2.4 2.6 2.6 4.1 4.2 4.4 5.4 6.8 7.7 11.3 11.9 12.8

Bore dia. (mm) 50 55 60 65 70 75 80 85 90 95 100 105 110 120 130 140 150 160 170

Double-row cylindrical roller bearings NN30 NN39 1.4 2.0 2.1 2.2 3.2 3.5 4.7 4.9 6.5 6.6 6.8 9.3 11.0 12.5 18.0 20.0 23.0 29.0 38.0 -- -- -- -- -- -- -- -- -- -- 4.5 4.6 4.8 6.5 8.5 9.4 14.5 16.0 16.0

* Do not operate bearings at full spindle speed when bearings are first installed. It is necessary to break the grease in. Contact NSK for assistance.

PRELOAD

The main purpose for applying a preload to machine tool spindle bearings is to increase their rigidity, improve running accuracy, and prevent sliding of the rolling elements at high speed. Usually a preload is applied to bearings by using two or more in combination, such as angular contact ball bearings or tapered roller bearings. Cylindrical roller bearings can be preloaded by making the radial internal clearance slightly negative. If the preload is larger than necessary, abnormal heat generation, increased frictional torque, reduced fatigue life, etc. may occur. The amount of preload should be carefully determined considering the operating conditions and the purpose of the preload. Generally, as speed increases, the preload selected should be reduced.

DUPLEX BACK-TO-BACK (DB)

DUPLEX FACE-TO-FACE (DF)

DUPLEX TANDEM (DT)

BALL SCREW BEARING INTERCHANGE INFORMATION

NSK 20 TAC 25 TAC 30 TAC 35 TAC 40 TAC 50 TAC 60 TAC 20 23 38 44 57 76 101 TAC TAC TAC TAC TAC TAC TAC

1

RHP 47BDF 62BDF 62BDF 72BDF 72BDF 100BDF 120BDF 47xBDF 62BDF 72BDF 76BDF 90ADF 110ADF 14ADF BSB020047DF BSB025062DF BSB030062DF BSB035072DF BSB040072DF BSB050100DF BSB060120DF BSB078DF BSB093DF BSB150DF BSB175DF BSB225DF BSB300DF BSB400DF

FAFNIR MM20BS47DF MM25BS62DF MM30BS62DF MM35BS72DF MM40BS72DF MM50BS100DF MM60BS120DF MM9306WI2HD MM9308WI2HDF MM9310WI2HDF MM9311WI3HDF MM9313WI3HDF MM9316WI3HDF MM9321WI3HDF

BARDEN L2047HDF L2562HDF L3062HDF L3572HDF L4072HDF ­ ­ L078HDF L093HDF L150HDF L175HDF L225HDF L300HDF L400HDF

SKF BSD BSD BSD BSD BSD BSD 2047 C/DF 2562 C/DF 3062 C/DF 3572 C/DF 4072 C/DF 50100 C/DF ­ C/DF C/DF C/DF C/DF C/DF C/DF C/DF

METRIC

BDAB634200 BDAB634201 BDAB634202 BDAB634203 BDAB634204 BDAB634205 BDAB634206

1. Also available as single universal (SU) or duplex universal (DU) Note: Quad Sets: NSK=DFF, Fafnir=DU, Barden=DFTT, SKF=QFC

INCH

NSK

Standard Ultra-High Fafnir Barden NDH MRC SKF FAG

7200CTY*P4(PA7) ­ 2MM200WI* 7200A5TY*P4(PA7) ­ 3MM200WI* 7000CTY*P4(PA7) 00BNC10T*P4(PA7) 2MM9100WI* 7000A5TY*P4(PA7) ­ 3MM9100WI* 7900CTY*P4(PA7) 00BNC19T*P4(PA7) 2MM9300W0CR* 7900A5TY*P4(PA7) ­ ­ ­ ­ 7200CTY*P5(PA5) ISO Class 5 7200A5TY*P5(PA5) ­ ­ or ­ ­ 7000CTY*P5(PA5) AFBMA ­ ­ 7000A5TY*P5(PA5) ABEC5 ­ ­ 7900CTY*P5(PA5) ­ ­ 7900A5TY*P5(PA5)

ISO Class 4 or AFBMA ABEC7

200H* 2200H* 100H* 2100H* ­ ­ ­ ­ ­ ­ ­ ­

Q20200*7 QH20200*7 Q0L200*7 QH0L00*7 ­ ­ Q20200*5 QH20200*5 Q0L200*5 QH0L00*5 ­ ­

200R*7B 7200*7B 100KR*7B 7100R*7B 1900R*7B ­ 200R*5B 7200*5B 100KR*5B 7100R*5B 1900R*5B ­

7200CP4* 7200ACP4* 7000CP4* 7000ACP4* 71900CP4* 71900ACP4* 7200CP5* 7200ACP5* 7000CP5* 7000ACP5* ­ ­

B7200CTPAP4* B7200CETPAP4* B7000CTPAP4* B7000ETPAP4* B71900CTPAP4* B71900ETPAP4* B7200CTPAP5* B7200CETPAP5* B7000CTPAP5* B7000ETPAP5* ­ ­

7200CTP4* 7200ETP4* 7000CTP4* 7000ETP4* 7900CTP4* 7900ETP4* 7200CTP5* 7200ETP5* 7000CTP5* 7000ETP5* 7900CTP5* 7900ETP5*

1. Phenolic cage = "T", Polyamide cage = "TY" Notes: Underlined digits (00) vary with bearing size Asterisks indicate the position of the preload designation for Universal Duplex Bearings.

PRELOAD DESIGNATION

Preload Light Medium Heavy NSK DUL DUM DUH

FOR

UNIVERSAL DUPLEX BEARINGS

Fafnir DUL DUM DUH Barden DL DM DH NDH DTL DTX DTT MRC DUL DUM DUH SKF DGA DGB DGC FAG UL UM US RHP DUL DUM DUH

CORPORATE OFFICE 3861 Research Park Drive P Box 1507 .O. Ann Arbor, Michigan 48106-1507 (800) 675-9930 Fax: (734) 761-9503 www.nsk-corp.com ATLANTA, GEORGIA 5575 Gwaltney Drive Atlanta, Georgia 30336-2649 (404) 349-2888

INDIANAPOLIS, INDIANA 5550 Progress Road Park Fletcher Indianapolis, Indiana 46241-4331 (317) 247-4724

CERRITOS, CALIFORNIA 13921 Bettencourt Street Cerritos, California 90701-3512 (800) 421-1458 Fax: (562) 926-3558

BLOOMINGDALE, ILLINOIS 250 Covington Drive Bloomingdale, Illinois 60108 (708) 924-8000

NSK-RHP CANADA, INC. 5585 McAdam Road Mississauga, Ontario L4Z 1N4 Canada (905) 890-0740

MTB-0499 ©NSK Corp. 1998

HIGH-PRECISION SINGLE-ROW ANGULAR CONTACT BALL BEARINGS FOR MACHINE TOOL APPLICATIONS

FORMULATION

OF

BEARING NUMBERS

Conventional Type 72, 70, 79 Series

70 16 A5 T DB L P4 Precision Class: P5 - ISO Class 5 PA5 - ABEC 5 P4 - ISO Class 4 PA7 - ABEC 7 P2 - ISO Class 2 PA9 - ABEC 9 Uxx or Pxx - Special accuracy class or features Preload: C2 - Ultra Light L* or C7* - Light M* or C8* - Medium H* or C9* - Heavy Gxx - Preload in Kfg (G5=5 Kgf) CPxx - Median Preload in Microns (CP10=10µ m) CAxx - Median Axial Clearance in Microns (CA15=15µ m) *Although these loads are equivalent in scope, they may not be equal in magnitude Mounting Configuration: DB - Duplex, Back-to-back DF - Duplex, Face-to-face DT - Duplex, Tandem DU - Duplex, Universal DBD, DFD, DTD - Triplex DBB, DFF, DBT - Quadruplex SU - Single Universal Retainer: No Suffix - Machined Bronze T - Phenolic, Machined TY - Nylon, Molded MA - Machined Brass Cage

Special High-Speed Type BNC 10, BNC 19 Series

80 BNC 10 TY DB L P4 Precision Class: P4 - ISO Class 4 PA7 - ABEC 7 P2 - ISO Class 2 PA9 - ABEC 9 Uxx or Pxx - Special accuracy class or features Preload: EL - Extra Light L - Light Gxx - Preload in Kgf (G5=5 Kgf) CPxx - Median Preload in Microns (CP10=10µm) CAxx - Median Axial Clearance in Microns (CA15=15µm) Mounting Configuration: DB - Duplex, Back-to-back DF - Duplex, Face-to-face DT - Duplex, Tandem DU - Duplex, Universal DBD, DFD, DTD - Triplex DBB, DFF, DBT - Quadruplex SU - Single Universal

Retainer: T - Phenolic, Machined TY - Nylon, Molded MA - Machined Brass Cage

Contact Angle: A = 30° B = 40° A5 = 25° C = 15° Bore Diameter Designator: Bearing Series:

Dimension Series: 10 : Same bore diameter, outside diameter, and width as the 70 series 19 : Same bore diameter, outside diameter, and width as the 79 series

Bearing Type Symbol: BNC - Contact Angle=15° BNT - Contact Angle=12° Nominal Bore Diameter:

UNIVERSAL COMBINATION BEARINGS

Standard angular contact ball bearings can be used only in previously fixed arrangements (DB, DBD, DBB, etc.). The need for universal combination bearings is increasing, especially outside Japan (Europe, U.S.A.) where universal combination bearings are dominant. Considering this, NSK established specifications for universal combination angular contact ball bearings and now produces them upon request.

f: Standout of front face b: Standout of back face Fig. 1 Standout of Inner & Outer Rings

UNIVERSAL DUPLEX DU A single bearing has the same amount of standout on both the front and F backface (F i g . 1 ) (f=b) and it is a specified amount for each standard preload. The size variation of the bore and outside diameters of paired bearings is adjusted to less than 1/3 of the tolerance. Therefore, one pair of bearings can be used in any combination of DB, DF, DT. Single Universal SU bearings of which the front face and back face standout are adjusted to be equal are also manufactured. By matching bearings having the same bore diameters and outside diameters, any 2, 3, or 4 rows combination is possible.

NSK SUPER PRECISION UNIVERSAL DUPLEXED ANGULAR CONTACT BEARINGS

FEATURES

· State-of-the art preload control · Bores and O.D.'s matched within 1/3 of tolerance range · High Point of Eccentricity marked ` on inner and outer rings · Packaged marked with actual bore, O.D., and width deviation from nominal (units are microns µm) · High performance nylon cage for most popular sizes

SETS OF 2 BEARINGS

COMBINATION

OF

ANGULAR CONTACT BALL BEARINGS

Back-to-Back arrangement DB

SETS OF 3 BEARINGS

Face-to-Face arrangement DF

Tandem arrangement DT

DBD

SETS OF 4 BEARINGS

DFD

DTD

DBB

DFF

DTT

DBT

DFT

BALL SCREW SUPPORT BEARINGS

30 TAC 62 B DB C10 PN7A Precision Class: PN7A - ISO Class 4 (ABEC 7) Modified; More Stringent Standard for Axial Runout Uxx or Pss - Special accuracy class or features PN7B - Bore and O.D. tolerance is tighter; used with SU combination Preload: C10 - Metric Series C11 - Inch Series

Mounting Configuration: DB - Duplex, Back-to-back DF - Duplex, Face-to-face DT - Duplex, Tandem DU - Duplex, Universal DBD, DFD, DTD - Triplex DBB, DFF, DBT - Quadruplex SU - Single Universal; Replaces all above mounting configurations when same part number (preload) is selected.

Internal Specifications: A - Standard Capacity B - High Capacity & Higher Speed (Replaces "A" type)

Bearing O.D.* (mm):

Contact Angle TAC - Bearing Type Symbol Bearing Bore* (mm): *For inch series bearings, the fractional portion of the size is omitted.

Characteristics Basic dynamic load rating N[kgf] 21 900 (2240) 21 900 (2240) 28 500 (2910) 29 200 (2980) 31 000 (3150) 31 500 (3250) 59 000 (6000) 33 000 (3350) 61 500 (6300) 63 000 (6400) 63 000 (6400) 67 500 (6850) 67 500 (6850)

DB (DF)

Characteristics

DB (DF) Basic dynamic load rating N[kgf] 21 900 (2240) 28 500 (2910) 31 500 (3250) 33 000 (3350) 32 000 (3300) 35 500 (3600) 88 500 (9050)

Metric Bearing No. 17TAC47B 20TAC47B 25TAC62B 30TAC62B 35TAC72B 40TAC72B 40TAC90B 45TAC75B 45TAC100B 50TAC100B 55TAC100B 55TAC120B 60TAC120B

Limiting speed rpm 6 000 6 000 4 500 4 300 3 600 3 600 3 000 3 200 2 600 2 600 2 600 2 200 2 200

Limiting axial load N[kfg] 26 600 (2710) 26 600 (2710) 40 500 (4150) 43 000 (4400) 50 000 (5100) 52 000 (5300) 89 500 (9150) 57 000 (5800) 99 000 (10100) 104 000 (10600) 104 000 (10600) 123 000 (12600) 123 000 (12600)

Preload DB-DF C10 N[kgf[ 2 150 (220) 2 150 (220) 3 150 (320) 3 350 (340) 3 800 (390) 3 900 (400) 5 000 (510) 4 100 (420) 5 900 (600) 6 100 (620) 6 100 (620) 6 650 (680) 6 650 (680)

Lube Qty [cm3/brg] 2.0 2.0 2.8 3.0 3.5 3.6 8.2 3.9 9.0 9.5 9.5 11.2 11.2

Limiting Inch speed rpm Bearing No. 6 000 20TAC47XB 23TAC62B 38TAC72B 44TAC76B 57TAC90A 76TAC110A 101TAC145A 4 500 3 600 3 200 2 600 2 000 1 600

Preload Limiting axial load DB-DF C11 N[kgf] N[kfg] 3 150 26 600 (320) (2710) 40 500 (4150) 52 000 (5300) 57 000 (5800) 44 600 (4550) 57 400 (5850) 134 300 (13700) 4 500 (460) 5 800 (590) 6 650 (680) 7 750 (790) 10 000 (1020) 13 300 (1360)

Lube Qty [cm3/brg] 2.1 3.0 3.8 4.2 3.9 5.0 16.0

CYLINDRICAL ROLLER BEARINGS

FORMULATION

NN

OF

BEARING NUMBERS

3 0 17 MB KR CC1 P4 Precision Class: P5 - ISO Class 5 P4 - ISO Class 4 P2 - ISO Class 2 Uxx or Pxx - Special accuracy

PA5 PA7 PA9 class

or

ABEC 5 ABEC 7 ABEC 9 features

Radial Clearance: CC9 - Less than CC1 CC3 - Larger than CC CC1 - Less than CC2 CC4 - Larger than CC3 CC2 - Less than CC CC5 - Larger than CC4 CCG [ ] - Special, Median Clearance in Microns (CCG 15=15µ m) Note: CC1 most commonly used in machine tool applications

Bore Configuration: K - Tapered Bore (1:12) Replaced by "KR" KR - Ultra Precision Tapered Bore (1:12) Retainer Symbol: M - Brass, Single Piece Machined, Inner Ring Guided MB - Brass, Machined Split Type, Roller Guided T - Nylon, Molded, Roller Guided Note: Deleted Symbol Implies "M" Type Bore Diameter Designator: Diameter Series: Width Series: Cylindrical Roller Designator: NN - Double Row, Inner Ring Guided Rollers N - Single Row, Inner Ring Guided Rollers NNU - Double Row, Thin Section Outer Ring Guided Rollers NU - Single Row, Outer Ring Guided Rollers

THRUST ANGULAR BALL BEARINGS FOR SPINDLE APPLICATIONS

100 BA 10X TY DB L P4A 100 TAC 20X PN7 +L C6 Preload Class: C6 : Standard Preload for Grease Lubrication C7 : Standard Preload for Oil Lubrication Spacer (Inner Ring): Preload Class: PN7 : ISO Class 4, O.D. is Special Dimension Series: 20D - Standard Capacity 29D - Standard Capacity 20X - High Speed Type w/Revised Internal Features 29X - High Speed Type w/Revised Internal Features Bearing Type Symbol: Bearing Bore Diameter (mm): Precision Class: P4A : ISO Class 4, O.D. is Special Preload: L: : Standard Preload EL : Standard Preload for High Speed Applications Combination: DB : Back to Back Duplex Retainer: TY : Nylon, Molded No suffix: Machined Bronze Dimension Series: 10X : Arranged with NN30XX Series Bearing Type: BA (Contact angle, 30°) BT (Contact angle, 40°) Bearing Bore Diameter (mm):

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