Read Cranfield Energy text version

Alleviating Compaction

Pea Harvest:

Tractor and trailer GPS Log This is for only 1 tractor and trailer of a pair:

Field area is 14.8 ha

Tractor wheel marks total 20km (1 tractor)

Specific resistance and energy requirements

Ploughing on trafficked and non-trafficked fields

System

Trafficked Non-trafficked

kN/sq.m

107 42

kJ/ha

117 47

After: Chamen, Silsoe Research Institute

Traffic control effects on field operations and energy (MJ/ha) needs

No traffic

Harrow Drill Roll 25 27 27

Trafficked

Spring tine Power Harrow Harrow Drill Roll 57 108 29 31 30 255

TOTAL

79

After: Chamen,SRI

A 3.23 x INCREASE in ENERGY

Compaction:- Tyre load and inflation pressure

N.B. Ignoring carcass effects

· Pressure = Weight/Area · Area = Weight/Pressure · Weight = Pressure x Area

W

Carcass stiffness effects (approximate)

Tractor tyre Combine tyre + 1.5 psi + 7.0 psi

P

A

Low ground pressure tyre

+ 0.7 psi

Effects of load, inflation pressure and speed

LOW SPEED HIGH SPEED

Weight Low Pressure High

Weigh Low Pressure Low

Weight High Pressure Low

Weight High Pressure Low

4 3

3 2 1 Pressure distribution

3

3

2

2 1 1

2 1

Pressure has the greatest influence on the degree of compaction and load influences the depth of soil compaction

Surface effects

Sub surface effects

0.6m

Subsurface effects - pans

Sub-soiling benefits are limited to:* sandy soils

with

* spring sown crops

in

* years of moderate to severe drought

After: Soane, Godwin &

2 Problem areas

1. Re-compaction of loosened soil during crop establishment 2. Further re-compaction of settled soil at harvest time Which resolve into : 1. Size 2. Weight 3. Pressure

Harvesting

Heavy machines and getting heavier?

Gross weight, tonnes

70 60 50 40 30 20 10 0

ls

Dr il Sp

Gross weight of a range of vehicles

After: Erickson et al 1974

ra ye r Sp re ad er Tr ac to r Co m bi ne Tr ai le r Ta nk er Be Tr uc et k Ha rv Pe es a te H r ar ve st er

Inflation presure, psi

120 100 80

60 40 20 0

ls

Dr il Sp ra ye r Sp re ad er Tr ac to r Co m bi ne

Tyre inflation pressure of a range of vehicles

After: Erickson et al 1974

Tr ai le r Ta nk er Tr Be uc et k Ha rv es te r

Options for reducing compaction

Options

Controlled traffic

Traffic reduction

Uncontrolled traffic

Permanent tracks

Temporary track

Low mass

Medium mass

High mass

Wide wheels

Restricted?

Gantries

Tramlines

Load reduction

Lower inflation pressure New wheel/track systems

After: Soane, 1981

Extended track widths

Linked operations

Tread lightly - the alternatives

4 pairs of equal size dual tyres .v. Rubber tracks

66 in Typical Weight = 18tons / 40,000lbfs Total contact area = 3,920 in2 Power = 375 hp 6426in2 6.2 psi 30 in

Average Contact Pressure = 10.2 psi (MINIMUM)

After: Goodyear & Caterpillar, 2001

Tyre selection

Fit the largest section/diameter tyre at the lowest safe working pressure

Trailers can be the main culprit

Terra (low ground pressure) tyres

Duals

Dual tyres on combine & tractor + chaser wagon

Narrow section

Go for diameter- large contact patch

Beet Harvester ~ Tyre Configuration

55 tonnes

Inflation pressures

55 tonnes

800-70x38 @ 1.6-1.9 bar

Central tyre inflation systems are available for conversion from field to road to field inflation pressures

Compaction issues

25 tonnes 2 bar (1 bar better) 20 + tonnes 7 bar

Laboratory studies

3 tyre sections (500/65-22.5, 700/50-26.5, 800/40-26.5) 3 inflation pressures(13, 23, 33 psi) 3 soil bearing capacities 1 weight (4.5 tonnes)

Reduced Tyre Pressures and Central Tyre Inflation systems

N.B. Lower pressure tyres would need Central Tyre Inflation System to enable safe road use Rut Depth

200mm Inflation Pressure Road/High speed 33 psi Field/Low speed 13 psi

Initial density 1.25 g/cc

140 mm

Effect of inflation pressure on soil strength

Penetration resistance, MPa

Depth, cm

Stranks, Dresser and Godwin, 2004

Rubber Tracks

Effect of track weight distribution

18.5t Challenger on 2 x 2.1m2 rubber tracks average contact pressure 6.5psi?

Pressure, psi 45

Balanced

Original

30

48%

15

0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6 Rydberg,2003

Time, seconds

Compaction alleviation - Rubber tracks

28 tonnes

32 tonnes

Extra cost £1/ha over the working life of the combine

Track and Tyre Evaluation

0 - 14t 0 - 12t

Deformation measurement

+/- 2mm

Soil deformation

Tyre Track

200 300 400 500

200 300 400 500

Depth (mm)

600 700 800 900 1 000 0 200 400 600 800 1 000 1200 1400

Depth (mm)

600 700 800 900 1 000 0 200 400 600 800 1 000 1200 1400

Width (mm)

Width (mm)

Compaction reduction - Rubber tracks 11 t

30 t

Deformation (m m) -20 0 100 200 0 20 40 60

Displacement (mm)

80 100 120

Depth (mm)

900 followed by 700 300 400 500 600 700 900 followed by 500 Track followed by 700 Track followed by 500 Dominator LSD

33 t

Track pressure distribution

2

Sensor @ 250mm

1.5

Ceramic pressure transducer

Pressure

Pressure

1

0.5

0 8.5 9 9.5

Track position 10 10.5 11

11.5

12

12.5

Pressure from a Truck tyre:

5 t, 7bar

10 9

Sensor @ 250 mm depth

Max Pressure = 9.27 bar

pressure (bar)

8 7 6 5 4 3 2 1 0 -1 14 15 16 17 18 19 20

time (s)

Effect of wheel/track system on pressure at 250mm 7

6 5

Pressure (bar)

4 3 2 1 0

road harvester 5t, 7bar 10t, 2bar rear tractor 2t, 2bar harvester 10t, 1bar rear tractor 2t, 1bar track 12t harvester 5t, 2bar dual harvester 2t, 1bar 5t, 1bar track 5t

Effect of ground drive and depth on soil pressure

Pressure (bar)

0 0 -100 -200 Tractor 2t-2bar 1 2 3 4 5 6 7 Track 5t Road 5t-7bar Tractor 2t-1bar

Depth (mm)

-300 -400 -500

Dual 2t-1bar

Harvester 10t-2bar

Harvester 10t-1bar Harvester 5t-1bar Harvester 5t-2bar Track_12t

-600

-700

Controlled Traffic Systems: <10% surface wheeled

· Simple concept · Standardise wheel centres · Industry resistance to change in broad acre crops · Narrower track solutions under investigation

After: Tullberg et al (2003)

Tillage and traffic effects on runoff

Results from Queensland

1354 mm rain in 2 years

Wheeled mm Conventional Tillage 322 % 100% Controlled Traffic mm 266 % 83%

Zero Tillage

282

88%

166

52%

After: Tullberg, 1996

Yield from Low Ground Pressure Trial

Cranfield University and TAG

Plot 7 Zero Traffic

Plot 8 Normal traffic

Plot 9 Zero traffic +tracked combine

12. 52 t/ha

0.84t/ha

12.14t/ha

After: Phillpot, Stobart, Mouasen and Godwin, 2008

Effective subsoiling

Limited evidence of crop response to deep loosening in UK soils unless for spring sown crops in sandy soils in years with low rainfall

Tramline management

Cross drain with mole plough OR

Chisel or side inclined tines on upper tramline wheelmark only

Runoff

Conclusions

· Do all you can to reduce load and pressure · Spread load where possible · Keep compaction as shallow as possible ­ easier and cheaper to remove · Minimise random traffic · Work in sensible patterns · If damage occurs repair it as soon as is practicable · Follow the soil loosening advice given earlier

From:

Cross Compliance

Guidance for Soil Management

Defra 2005

Practical Aspects

Soil disturbance from subsoilers & track and tyre systems.

Whole Machine Comparison

Deformation (mm) -15 0 100 200 5 25 45 65 85 105

900/10.5/1.9 900/10.5/1.9700/4.5/1.0 900/10.5/1.9500-70/4.5/2.3 T12 T12-700/4.5/1.0 T12-50070/4.5/2.3 LSD

Depth (mm)

300 400 500 600 700

Track system

Tyre system

Case study

Considering the farm given in the Appendix a. What soil problems may arise on the different soils requiring tillage to alleviate and during the actual tillage operations? Indicate the likely nature, extent and depth of the problems where appropriate, relating them to different working conditions. b. What tillage systems would be appropriate for establishing cereals after harvest? Indicate likely working depths, equipment needs and potential workrates. c. Considering tyres/tracks and field operating procedures, indicate the opportunities which would be available to reduce soil problem and hence future tillage needs i. with existing equipment ii. when replacing equipment

APPENDIX Soil types: Chalky and sandy soils

Area: 950 ha (400 ha cereals) Soils: chalky soils on slopes, a shallow clay cap Loamy sand/sandy loam soils on flat areas, some with inherent high water table Crops/succession: sugar beet, potatoes, vegetables, cereals Root crops irrigated Cereals follow both root crops and cereals Root crops usually follow cereals Equipment weights and pressures: Tractors: Wheel: 150 ­ 190 hp 9 tonnes Ploughing tractor 18 ­ 20 psi Seedbed work, duals 10 psi Track: Cat 55 for most seedbed work 6-7 psi Trailers: Tandem axle 11 tonne 45 ­ 50 psi 14 tonne 45 ­ 50 psi 17 tonne Potato boxes 60 psi Combine: 25 tonne 30 ­ 35psi Sugar beet harvester: 6-row, full tank 35-40 tonne 40 ­ 45 psi Sprayer: 3600 l capacity tank, terra tyres 9 psi, narrow tyres 35-40 psi

APPENDIX Soil types: Chalky and sandy soils

Area: Soils:

950 ha (400 ha cereals) chalky soils on slopes, a shallow clay cap good soil water holding capacity / tramline erosion/ runoff Loamy sand/sandy loam soils on flat areas, some with inherent high water table capping/slumping Crops/succession: sugar beet, potatoes, vegetables, cereals beds/controlled traffic consider drainage Root crops irrigated capping Cereals follow both root crops and cereals could be damaged after beet harvest/deep loosen-as and when Root crops usually follow cereals Equipment weights and pressures: Tractors: Wheel: 150 ­ 190 hp 9 tonnes Ploughing tractor 18 ­ 20 psi consider move to tracked tractor/reduced tillage for

cereals

Track: Trailers:

Seedbed work, duals Cat 55 for most seedbed work Tandem axle 11 tonne 14 tonne 17 tonne

10 psi 6-7 psi could reinvest in larger version next time around to

increase work rates

45 ­ 50 psi 45 ­ 50 psi Potato boxes 60 psi

- larger tyres/lower pressure/chaser bins

Combine: 25 tonne 30 ­ 35psi -rubber tracks?? Sugar beet harvester: 6-row, full tank 35-40 tonne 40 ­ 45 psi contractor machine with larger tyres Sprayer: 3600 l capacity tank, terra tyres 9 psi, narrow tyres 35-40 psi improve tramline management Operating procedures Large fields, harvesters unloading into trailers within fields. ­ chaser bins

John Dale Seed Hawk Tines

·1+2 Seed Location ·3 Packed Surface ·4 Tungsten Carbide Cutters ·5 Pneumatic Packer / Depth Wheel (good mud release) ·6 Seed Coulter (½" (12.5mm) wide) ·7 Seed Drop Tube ·8 Seed Coulter ·9 Trip plate ·10 Chain ·11 Depth Lock Bolt ·12 Depth Gauge (accurate to 1/8") (3mm) ·13 Hanging Bracket ·14 Hydraulic Cylinder ·15 Placement Arm ·16 Seed Drop Tube email > [email protected] tel > 01652 653326

Practical application for field vegetables

RTK-GPS enables < +/- 20 - 30 mm positional error. Issues of repeatability and cost are being addressed

After: Chamen (2007)

Controlled traffic system for vegetable production using RTK-GPS and 300 mm wide rubber tracks.Track positions are at 3.15 m centres

After: Vermuelen (2006)

Dual-Trac for narrower track width tractors

·Assisted by "Autosteer" ·John Deere tractors with "independent link suspension for the front axle" ·Also use for harvesters

8 m seed drill 8 m harvester 24 m chemical application

3m

2m

After: Shaw and Chamen 2005

After: Shaw and Chamen (2005)

Moore Unidrill

Information

Cranfield Energy

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