Effect of varied approach angle on high speed moldboard plow performance

100 Pages·2016·9.42 MB·English

by  James Henry Eidet

Iowa State University Capstones, Theses and
Retrospective Theses and Dissertations
Dissertations
1974
Effect of varied approach angle on high speed
moldboard plow performance
James Henry Eidet
Iowa State University
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Recommended Citation
Eidet, James Henry, "Effect of varied approach angle on high speed moldboard plow performance" (1974).Retrospective Theses and
Dissertations. 14475.
https://lib.dr.iastate.edu/rtd/14475
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Effect of varied approach angle
on high speed moldboard plow performance
by
James Henry Eidet
A Thesis Submitted to the
Graduate Faculty in Partial Fulfillment of
The Requirements for the Degree of
MASTER OF SCIENCE
Major: Agricultural Engineering
Signatures have been redacted forprivacy
Iowa State University
Ames, Iowa
197if
ii
TABLE OF CONTENTS
Page
GLOSSARY viii
INTRODUCTION 1
OBJECTIVES 5
LITERATURE REVIEW 6
Evaluation of Plow Performance 6
Physical condition of plowed land 6
Forces on the plow bottom 8
Evaluation of Plow Design Parameters Ik
Orientation of the tool 16
Width of cut 17
Surface shape 18
Width and hei^t of moldboard 19
EXPERIMENTAL WORK 22
Description and Preliminary Preparation of Equipment 22
Test Procedure 25
Field tests 25
National Tillage Machinery Laboratory tests 51
Description of test facility 51
Soil bin preparation procedure 52
Soil data collection 56
Design of experiment 57
Data analysis and acquisition Zfl
RESULTS AND DISCUSSION Z^5
CONCLUSIONS 56
ill
Page
SUMMARY 57
RECOMMENDATIONS FOS FURTHER RESEARCH 59
REFERENCES 60
ACKNOWLEDGEMENTS 65
APPENDIX A: SOIL DATA 6if
APPENDIX B: MOLDBOARD PLOW AND COULTER FORCE DATA 73
iv
LIST OF TABLES
Page
Table 1. The relation of colloid content to B Phase friction 11
Table 2. Design parameters for a oph and a 5 laph moldboard
(Sohne and Moller, 1962) 20
Table 3» Number and type of soil bin preparations used in the
experiment 38
Table Analysis of variance for draft of model 392 as a function
of approach angle at 2, if, 6, and 8 mph in all soil types
combined 33
Table 5' Analysis of variance for draft of model 387 as a function
of approach angle at 2, if, 6, and 8 mph in Norfolk sandy
loam 53
Table 6. Average soil properties for each soil bin preparation 65
Table 7» Soil data for each sample taken 66
Table 8* Composite force and regression data for high speed plow
bottom (model 392) tested in Lakeland loamy sand 73
Table 9. Composite force and regression data for high speed plow
bottom (model 392) tested in Norfolk sandy loam 75
Table 10. Composite force and regression data for high speed plow
bottom (model 392) tested in Decatur clay loam 77
Table 11. Composite force and regression data for high speed plow
bottoms (models 387 and 392 combined) tested in Norfolk
sandy loam 79
LIST OF FIGURES
Page
Figure 1. A typical curvc showing the effect of soil moisture
content on friction values. The B Phase is classified
as the pure friction phase, the C Phase as the adhesion
phase and the D Phase as the lubrication phase (Nichols,
1951, p. 521) 11
Figure 2. Coordinate system and parameters for moldboard plow
description 15
Figure 3. Plough body shapes for three different speeds of travel
with the same lateral velocity components of the soil
leaving the moldboard (Sohne, I960, p. 21) 21
Figure 4. Allis-Chalmers high speed moldboard plow bottom,
model 392 24
Figure 5. Allis-Chalmers general purpose moldboard plow bottom,
model 587
Figure 6- Grid board as positioned in furrow profile for tests
(furrow profile is for model 392 at mph with
approach angle reduced lO'^) 28
Figure 7. Furrow profile for model 392 at 8»0 mph with approach
angle reduced 10° 28
Figure 8. Furrow profile at two speeds for model 392 tested at
its design approach angle 30
Figure 9. Furrow profile at three speeds for model 392 tested
with design approach angle reduced 10° 30
Figure 10. Implement carrier showing position of plow bottom and
coulter as mounted on separate cantilever beam strain
gage dynamometers 3^
Figure 11. Overall view of complete test apparatus including the
power car, implement carrier, and instrument car 34
Figure 12. Top view of model 387 a-) design approach angle and
b) maximum approach angle reduction of 13° showing ef
fective width of share for a 12-inch furrow slice 39
Figure 13. Soil bin cross sectional view showing an assignment
of all treatments (approach angles)
Figure I4. Block diagram of the HTML data acquisition system as
used in the experiment 42
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Page
Figure Model 392 plow bottom operating at 8 mph witii three
different approach angles in Lakeland loamy sand
(width and depth of cut constant) k?
Figure 16. Plow draft versus speed for model 392 tested in
Lakeland loamy sand at four approach angles = 35 ) ^9
Figure 17• Plow draft versus speed for model 392 tested in
Norfolk sandy loam at four approach angles (0 = 35 ) 50
Figure 18. Plow draft versus speed for model 392 tested in
Decatur clay loam at four approach angles (jZ5 = 35 ) 52
Figure 19, Plow draft versus speed for model 387 at four approach
angles (0 = 45*^) and model 392 at one approach angle
(0 = 35^^) tested in Norfolk sandy loam 53
Figure 20. Penetrometer cone index versus depth for Lakeland
loamy sand, preparation 1 (model 392 tested) 68
Figure 21. Penetrometer cone index versus depth for Lakeland
loamy sand, preparation 2 (model 392 tested) 68
Figure 22. Penetrometer cone index versus depth for Norfolk
sandy loam, preparation 1 (model 392 tested) 69
Figure 23. Penetrometer cone index versus depth for Norfolk
sandy loam, preparation 2 (model 392 tested) 69
Figure 2if. Penetrometer cone index versus depth for Decatur
clay loam, preparation 1 (model 392 tested) 70
Figure 25. Penetrometer cone index versus depth for Decatur
clay loam, preparation 2 (model 392 tested) 70
Figure 26. Penetrometer cone index versus depth for Norfolk
sandy loam, preparation 3 (models 387 and 392 tested) 7I
Figure 27* Penetrometer cone index versus depth for Norfolk
sandy loam, preparation Zf (models 387 and 392 tested) 71
Figure 28. Coulter draft forces versus speed for model 392 and
model 387 in three soil types 8l
Figiire 29. Coulter vertical forces versus speed for model 392
and model 387 in three soil types (forces are negative) 82
Vll
Figure 30. Plow side force versus speed for model 392 tested in
Lakeland loamy sand at foiir approach angles (0 = 35 ) 83
Figure 31. Plow vertical force versus speed for model 392 tested ^
in Lakeland loamy sand at four approach angles (0 = 35 )
Figure 32. Plow side force versus speed for model 392 tested in
Norfolk sandy loam at four approach angles (i9 = 35 ) 85
Figure 33• Plow vertical force versus speed for model 392 tested^
in Norfolk sandy loam at foiir approach angles (0 = 35 ) 86
Figure 34. Plow side force versus speed for model 392 tested in
Decatur clay loam at four approach angles (0 = 35 ) 8?
Figure 35. Plow vertical force versus speed for model 392 tested
in Decatur clay loam at four approach angles (0 = 35 ) 88
Figure 36. Plow side force versus speed for model 387 at four
approach angles (0 = 45 ) and model 392 at one approach
angle (0 = 35°) tested in Norfolk sandy loam 89
Figure 37. Plow vertical force versus speed for model 387 at four
approach angles (0 = 45 ) and model 392 at one approach
angle (0 = 35°) tested in Norfolk sandy loam 90
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GLOSSARY
Draft: The horizontal component parallel to the direction of motion
of the force required to pull an implement.
Moldhoard plow bottom: A tillage tool consisting of a cutting edge and
a warped surface for loosening and inverting
the soil furrow slice.
a) Plow moldboard: The major warped surface of the plow bottom.
b) Plowshare: The part of the plow bottom which includes the
bottom cutting edge.
c) Shin: A warped surface of the plow bottom adjacent to the
fxirrow wall; vertical cutting edge when a coulter is
not used.
d) Frog: The structure which supports the plowshare, plow mold-
board, and shin.
Moldboard plow: A primary tillage implement consisting of one or
several plow bottoms plus associated frame and ac
cessories.
Specific plow resistance: The draft per unit of furrow cross sectional
area.
Tillage, high speed: A tillage operation utilizing velocities considered
to be higher than those velocities commonly used.
Tillage tool: An individual soil working element.
Tillage implement: The composite of the individual tillage tools,
structural components, wheels, control, and
shielding devices.
INTROBTJCTION
Increased productivity is the constant goal of every modern day
farmer. This increased productivity means for the farmer that he can
obtain a higher standard of living and at the same time produce food
and fiber for a hungry world. In tillage work this productivity is
measured in acres per hour, although other units can be used. An
eqiaation (Hunt, 1973* P* 4) for the productivity or actual field capacity
of a tillage implement can be written as:
AFC = (1)
where
AFC = Actual Field Capacity (acres per hour)
S = Speed (miles per hour)
W = Width (feet)
E = Field efficiency (decimal).
This equation for Actual Field Capacity or AFC defines the factors that
determine the capacity of an implement. To increase productivity, one
can 1) increase the field efficiency, 2) increase width, or 3) increase
speed.
The efficiency of the operation can be improved to increase the
actual field capacity. Time losses such as turning at the end of the
field, equipment adjustment, and maintenance reduce the field efficiency.
Reduction of time losses will increase the field capacity of siny given
operation.