Retro en Ingles

7/29/2019 Retro en Ingles

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A l l r i g h t s r e s e r v e d

Operating Techniquesfor the

Tractor-Loader-Backhoe

Revised

by Gary J. Ober

Equipment Training Resources

9245 Reseda Blvd. #740

Northridge, CA 91324

(818) 360-5431 FAX (818) 360-6758

For our complete catalog of heavy equipment safety andtraining products, visit our website at www.equiptrain.com



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This book is designed to provide accurate and authoritative information regarding the subject matter

covered. It is sold with the understanding that the publisher is not responsible for the actions of others.

Further, the publishers accept no responsibility for injuries or damages resulting from the intended use

or misuse of information contained herein.

First Edition ©1983 Gary J. OberRevised Edition © 1999, 2000 Gary J. Ober

All Rights Reserved. No part of this book may be reproduced in whole, in part, in any form,

or by any means, electronic or mechanical, including, but not limited to, photocopying, recording,

or by any information storage and retrieval system, without prior written permission of the publisher.

Library of Congress Catalog Card Number: 99-66158

Published by

Equipment Training Resources

9245 Reseda Blvd. #740Northridge, CA 91324

(818) 360-5431 FAX (818) 360-6758

www.equiptrain.com

ISBN 0-911785-01-9

Published in Northridge, California

Printed and bound in U.S.A.



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1. TLB Dimensions . . . . . . . . . . . . . . . . . . . . . 1

General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Weight Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Bulldozer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Skiploader. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

TLB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Universal Forces and Principles . . . . . . . . . . . . . . . . 4

Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Work Motion Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Momentum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Pitch of Slope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

General Slope Information . . . . . . . . . . . . . . . . . . . . . . 8

Percent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Degrees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Percent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Downhill Force – Force Down the Plane . . . . . . . . . . 10

Traction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Friction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Center of Gravity . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Important Factors Relating to Center of Gravity . . . 18

Weight of Materials and COG . . . . . . . . . . . . . . . . . . . 20

Effect of Slopes on COG . . . . . . . . . . . . . . . . . . . . . . . 21

Altering Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Truck Loading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Attachments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24COG Wrapup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Questions – Chapter 1 TLB Dimensions . . . . . . . . 26

2. Machine Control . . . . . . . . . . . . . . . . . . . . 33

Mental requirements . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Physical Requirements . . . . . . . . . . . . . . . . . . . . . . . . 33

Machine Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

Machine Response . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Mechanical Response . . . . . . . . . . . . . . . . . . . . . . . . 35

Older Machines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Loader Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Danger Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

On the Job . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Loader Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Hydralic Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Backhoe Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Backhoe Controls – 4-lever system . . . . . . . . . . . . . . . 40

Backhoe Controls – 3-lever system with foot swing . . . 41

Backhoe Controls – 2-lever system with “JD” pattern. . 42

Backhoe Controls – 2-lever system, excavator. . . . . . . 43

Practice Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Questions – Chapter 2 Machine Control . . . . . . . . . 48

3. Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

#1 Accident . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Safe Clothing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Seat Belt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Keep Your Machine Clean . . . . . . . . . . . . . . . . . . . . . 54

Safety Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Lock-out Safety Devices . . . . . . . . . . . . . . . . . . . . . . . 55

Parking Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

Worker Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

General TLB Safety . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Backhoe Accidents . . . . . . . . . . . . . . . . . . . . . . . . . . 58

TLB Accidents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

Rollover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Excavations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Excavation Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

Shoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Sloping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Spoil Quantities – Shoring vs. Sloping . . . . . . . . . . . . . 63

Transporting Wheeled Machinery . . . . . . . . . . . . . . 65

Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Questions – Chapter 3 Safety . . . . . . . . . . . . . . . . . 68

4. Maintenance . . . . . . . . . . . . . . . . . . . . . . . . 73

Operation and Maintenance Manual . . . . . . . . . . . . . . 73

Machine Components & Systems . . . . . . . . . . . . . . . . 74

Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Pre-Cleaner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Primary Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Secondary Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Greasing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

Warm-Up and Cooldown . . . . . . . . . . . . . . . . . . . . . . 79

Machine Life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Bucket Changing Tips . . . . . . . . . . . . . . . . . . . . . . . . 80

Questions – Chapter 4 Maintenance . . . . . . . . . . . . 84

5. Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

One Call System . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

The Limitations of the One Call System . . . . . . . . . 92The Good, the Bad, and the Ugly . . . . . . . . . . . . . . . . 92

How to Proceed with the Job . . . . . . . . . . . . . . . . . . 93

The “Four Stages of Alert” . . . . . . . . . . . . . . . . . . . . 94

Keys to Pipe Detection . . . . . . . . . . . . . . . . . . . . . . . . 94

Variables That Determine Pipe Breakage . . . . . . . . 95

Investigating Possible Utility Lines . . . . . . . . . . . . . 96

Working Range of the TLB When Locating Utilities. . . . 96

Digging Around Utilities . . . . . . . . . . . . . . . . . . . . . . . 97

Questions – Chapter 5 Utilities . . . . . . . . . . . . . . . 101

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Table of Contents



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6. Planning the Job. . . . . . . . . . . . . . . . . . . 107Placement of Spoil . . . . . . . . . . . . . . . . . . . . . . . . . 108Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108Precision Job Layout . . . . . . . . . . . . . . . . . . . . . . . 109Job-Planning Tips . . . . . . . . . . . . . . . . . . . . . . . . . . 109Questions – Chapter 6 Planning the Job . . . . . . . . 110

7. Set-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113Tripod Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115The Pivot Method . . . . . . . . . . . . . . . . . . . . . . . . . . 116Precision Set-up . . . . . . . . . . . . . . . . . . . . . . . . . . . 117Set-Up Techniques . . . . . . . . . . . . . . . . . . . . . . . . . 120Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122Questions – Chapter 7 Set-up . . . . . . . . . . . . . . . . 123

8. Footings . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127Precision, Skill, Concentration . . . . . . . . . . . . . . . . 127Footing Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128Precision Digging . . . . . . . . . . . . . . . . . . . . . . . . . . 129Elevation Importance and Checking Methods . . . . 129Laborer Involvement . . . . . . . . . . . . . . . . . . . . . . . . 132

Checking the Grade . . . . . . . . . . . . . . . . . . . . . . . . . 133Questions – Chapter 8 Footings . . . . . . . . . . . . . . 139

9. Job Site Cleanlinessand Cleanup . . . . . . . . . . . . . . . . . . . . . . . . 143

Shuttle Operations . . . . . . . . . . . . . . . . . . . . . . . . . 144Spoil Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144Importance of Excavation Cleanliness . . . . . . . . . 145Cleanup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145Questions – Chapter 9 Cleanliness and Cleanup . 153

10. Grading and Compaction . . . . . . . . 157Required Skills . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157Grading Techniques . . . . . . . . . . . . . . . . . . . . . . . . 157

Loader Grading Techniques . . . . . . . . . . . . . . . . . . 157Cutting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159Filling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160Fine Cutting Techniques for Hard Ground . . . . . . . . . 161Finish Grading . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163Backhoe Grading Techniques . . . . . . . . . . . . . . . . 168Compaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171Wheel Rolling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172Jetting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173Compaction Attachments . . . . . . . . . . . . . . . . . . . . 175Questions – Chapter 10 Grading and Compaction 177

11. Backhoe Techniques. . . . . . . . . . . . . 181Purpose of the Excavation . . . . . . . . . . . . . . . . . . . 181General Trenching Procedure . . . . . . . . . . . . . . . . . 182

Extendable Dipperstick Procedure. . . . . . . . . . . . 184Soft Ground Conditions . . . . . . . . . . . . . . . . . . . . . 186Hard Ground Conditions . . . . . . . . . . . . . . . . . . . . 186Stabilizer Usage and Technique . . . . . . . . . . . . . . . 187Digging Near a Wall or Fence . . . . . . . . . . . . . . . . . 188Digging Against A Wall . . . . . . . . . . . . . . . . . . . . . . . 191Specialized Job Tasks . . . . . . . . . . . . . . . . . . . . . . 192Tunneling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192

Potholing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194Cribbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196Cribbing Technique – Railroad Applications. . . . . . . . 196Loading Trucks with the Backhoe . . . . . . . . . . . . . 197Material Handling . . . . . . . . . . . . . . . . . . . . . . . . . . 200Handling Long Material . . . . . . . . . . . . . . . . . . . . . . . 200Land Clearing Procedures . . . . . . . . . . . . . . . . . . . 202

Clearing Techniques . . . . . . . . . . . . . . . . . . . . . . . . . 202Stump Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204How to Dig an Arc . . . . . . . . . . . . . . . . . . . . . . . . . . 205Tooth Grab Method . . . . . . . . . . . . . . . . . . . . . . . . . . 207Crossing Trenches. . . . . . . . . . . . . . . . . . . . . . . . . . 212Connecting Trenches . . . . . . . . . . . . . . . . . . . . . . . . 214Questions – Chapter 11 Backhoe Techniques . . . . 215

12. Loader Techniques . . . . . . . . . . . . . . . 221Principles of Operation . . . . . . . . . . . . . . . . . . . . . . 221Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224Filling the Bucket . . . . . . . . . . . . . . . . . . . . . . . . . . 225Soft Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227Hard Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230Loading Trucks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230Stockpiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233Ramp Stockpile . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233Related Techniques . . . . . . . . . . . . . . . . . . . . . . . . . 235Shuttle Operations . . . . . . . . . . . . . . . . . . . . . . . . . . 238Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242Related Techniques . . . . . . . . . . . . . . . . . . . . . . . . 242Questions – Chapter 12 Loader Techniques . . . . . 247

13. Demolition . . . . . . . . . . . . . . . . . . . . . . . . 251Preparation and Planning . . . . . . . . . . . . . . . . . . . . 252Efficiency of Job Completion . . . . . . . . . . . . . . . . . . 252Stockpiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252Material Separation . . . . . . . . . . . . . . . . . . . . . . . . . . 253Backhoe Techniques . . . . . . . . . . . . . . . . . . . . . . . 253

Prying Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254Concrete Breaking . . . . . . . . . . . . . . . . . . . . . . . . . . 255Roll-Out Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255Breaking Technique. . . . . . . . . . . . . . . . . . . . . . . . . . 256Positioning Pieces for Breaking . . . . . . . . . . . . . . . . . 256Loading Techniques . . . . . . . . . . . . . . . . . . . . . . . . 257Loading with the Backhoe . . . . . . . . . . . . . . . . . . . . 257Picking Up the Pieces . . . . . . . . . . . . . . . . . . . . . . . 258Natural Back-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259Positioning the Bucket . . . . . . . . . . . . . . . . . . . . . . . . 261No Back-up Technique . . . . . . . . . . . . . . . . . . . . . . . 263Lifting and Swinging . . . . . . . . . . . . . . . . . . . . . . . . . 264Loading with the Loader . . . . . . . . . . . . . . . . . . . . . 266Questions – Chapter 13 Demolition . . . . . . . . . . . . 271

AppendicesAppendix A – Natural Gas Dangers . . . . . . . . . . . . . 275Appendix B – Glossary . . . . . . . . . . . . . . . . . . . . . . . 277Appendix C – Index . . . . . . . . . . . . . . . . . . . . . . . . . 280Appendix D – Answer Key . . . . . . . . . . . . . . . . . . . . 285ETR Product Guide . . . . . . . . . . . . . . . . . . . . . . . . . . 297ETR Order Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298



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The tractor-Ioader-backhoe (or “TLB” as I’ll call it here) is a highly versatile,

productive piece of equipment. It’s ideal for most of the trenching that’s done

on a building site. It’s perfect for loading soil and heavy objects into a truck.

It handles light demolition well. And, of course, it backfills trenches and does

minor grading much faster than could be done by hand.

What You Need to Know

This book isn’t a technical manual. And it doesn’t cover any particular type of

TLB. The various manufacturers have all the technical manuals you’ll need on

the equipment they manufacture and sell. Nor does this book recommend

one brand of TLB over any other. They’re all good. What this book does is

explain in the most concise and direct way possible what you should know

for safety productivity of the TLB. Without this information, you would not be

aware of the potential for accidents, and the safety hazards that can cause

serious damage to people or property.

I’ve written this book for both the beginning and the experienced operator. It

begins with the basics, of course. But there’s plenty of useful information in

later chapters for even veteran operators. And I’ve never met an operator

who couldn’t learn a little more or get rid of a few bad habits. Certainly I

haven’t stopped learning about the TLB. In fact, during the writing and illus-trating of this revised edition, my own knowledge has been stretched into

new areas of understanding, and that information is presented in this book

for all to learn from. This highly technical information has been distilled into

easy to understand terms, and generously illustrated for your ease of under-

standing and for safe operation of these machines in the future.

Steps Toward Your Goal

As you read through the first chapters, you may feel that my descriptions

seem to cover a series of unrelated subjects and procedures. Be patient –

and learn these important principles as they are presented. As you read

further, you will notice that each bit of information becomes a part of a larger

process.

Later sections of this book emphasize the more technical aspects and diffi-

cult job situations, such as: tight work space, working around utilities, preci-

sion excavation and many more complicated tasks. Although many jobs do

not demand the highest degree of operating skills, mastering the machine

provides safety as well as the necessary skills to do precision work.

Introduction



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Learn the more demanding tasks and everything else will seem like a piece

of cake. That’s why I’ve emphasized techniques and work procedures that

cover “worst-case” situations.

Get Started Right

A word to beginners: There’s no substitute for practice, practice and morepractice. Just reading this book isn’t enough. It’s practicing what you’ve

learned here that makes you an expert. With time, operating a backhoe safe-

ly and productively will become as natural to you as driving a car or tying

your shoe.

And don’t be discouraged when you run into difficulty. The TLB is among the

most difficult pieces of heavy equipment to operate. There are two reasons:

First, it’s really two machines in one, with separate controls and operating

principles for each. Second, the TLB is used for so many different tasks and

procedures, that there’s a lot to learn. No matter how experienced you are,

there’s always another job yet to be attempted and mastered. And remember,

it is the operator’s job to find an intelligent, safe, workable solution to the job

at hand.

IMPORTANT

These machines are commonly called on for wide range of tasks, procedures,

and applications. Because of these wide ranging uses, I have used terminology

that will convey the exact thought of the author to the reader.

When “TLB” is used in this book, I am referring to the machine in general.

When the word loader is used in this book, I am referring to the machine being

used as a loader, moving on the site and using the loader bucket to perform

work. The machine could be grading, leveling, moving material, or loading

trucks.

When the word backhoe is used in this book, I am referring to the machine

being used as a backhoe, with the stabilizers down and the machine in a set

position.

Instructors, please note…

The Answer Key on pages 285–296 is perforated for easy removal, if desired.

If you choose to remove these pages, please return them to the students at theend of the course as they are an excellent review of the material.



CHAPTER 1 – TLB DIMENSIONS

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GeneralThe modern tractor-loader-backhoe is the mostversatile machine on today’s construction site. Itcan dig trenches, carry heavy materials in bulk,transport large objects, and work the earth in what-

ever way required for all modern construction,demolition or excavation projects. It has become

a common sight on city streets as well as in rurallocations.

Like any piece of complicated machinery, the TLBrequires a skilled operator who is proficient in theuse and control of the machine’s various func-tions. Becoming a skilled TLB operator requires athorough understanding of the machine’s capa-bilities, the principles behind its operation, and

thousands of hours of practice.

1. TLB Dimensions

dimensions 1. measure of the size and mass of anobject, such as length, height, width and weight.

9.1 ft

(2.8 m)

11.5 ft

(3.5 m)

6.9 ft (2.1 m)23.5 ft (7.16 m)

Fig 1-1 Typical dimensions of a TLB




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The primary step toward this understandingbetween man and machine is in learning the TLB’sdimensions. The TLB is generally more difficult tomaneuver than other types of heavy equipmentbecause it is over-long, over-high, and over-wide.Depending on the make and model, the TLB usu-ally has an overall length of twenty-three feet withthe boom drawn in. With the boom extended, themachine may stretch out to a length of thirty-fivefeet or more. It is at least twelve feet high with the

backhoe in transport position. With the two stabi-lizer arms lowered, the TLB takes up ten feet fromside to side. In short, the TLB can be an awkward

machine. Depending on the operator’s skill, how-ever, this awkwardness can be minimized andeven made to work to their advantage. One wayoperators can do this is by understanding theTLB’s weight distribution.

Weight DistributionThe TLB consists of three major components: 1)the tractor itself, which houses the diesel-pow-ered engine, the hydraulic pump and the cab; 2)the front loader assembly; and 3) the backhoeassembly, mounted on the rear. Because of theflexibility of these components, particularly thebackhoe itself, how the machine’s seven tons aredistributed frequently plays a major role in theplanning and completion of many jobs.

Approximately one-third of the total weight of theTLB is in the two-ton backhoe assembly, whosemain components include the boom, the crowd (orstick), the bucket and the stabilizer units (see Fig.1-2). Because of its location high above theground and far behind the wheelbase, the TLB’sweight transfers the entire machine’s center ofgravity upward as well as to the rear, when com-pared to other machines. This, in turn, makes themachine lighter on the front end and somewhattop-heavy. The positioning of this weight when

maneuvering around a job can be a constantsource of trouble for even an experienced opera-tor, since each job presents different demandsand hazards.

11.7 ft (3.53 m)

7.2 ft (2.18 m)

Fig. 1-3 Typical gross weight of TLB components

Fig. 1-2 Typical rear view of TLB

Loader – 2,100 lbs.Tractor – 6,625 lbs.Backhoe – 4,000 lbs.




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Universal Forces and PrinciplesOperating a TLB, or any other type of heavy equip-ment, is a construction trade that is unique in theindustry. This is because of the great weightsinvolved with the equipment and the materialsbeing handled. The high weights involved in oper-ating “heavy” equipment bring with them theunbending laws of physics.

If we were to look at a TLB in operation strictly froma physics viewpoint, it would be: a very HEAVY

MACHINE… MOVING around the job site… andmoving very HEAVY materials.

The weight of a working TLB can vary from 14,000to well over 25,000 lb. That’s 7 to 12 tons ofmachine and materials, working and movingthrough a busy job site, all day, every day.

In order for this to be accomplished with safetyand productivity, the operator must understand

the UNIVERSAL FORCES AND PRINCIPLESthat govern weight and movement.

UNIVERSAL FORCES AND PRINCIPLES applyto operating the TLB in the following ways:

1. There are physical forces and principles thatact on a TLB.

2. These forces have both a constant and a vari-able effect on the machine.

3. These forces have a strong effect on the con-

trol and safety of the machine.4. These forces can and must be limited, con-trolled and counteracted by the operator forsafety and control.

In order for you to safely move both machine andmaterials, you must first understand the UNIVER-SAL FORCES AND PRINCIPLES and how theyrelate to operating heavy equipment.

MOTION

MOMENTUM

TONS

DOWNHILL

FORCE

PITCH OF

SLOPE

CENTER OF

GRAVITY

C G

WEIGHT

TONS

TRACTION

FRICTION

“The high weights involved in operating heavy

equipment bring with them the unbending laws

of physics.” — Gary J. Ober 1999



Equipment Training Resources 9245 Reseda Blvd. #740Northridge, CA 91324Phone: 818/360-5431Fax: 818/360-6758www.equiptrain.com

The modern Tractor-Loader-Backhoe

has become the most useful machine in

general construction, and it has gained

that reputation since its introduction in the

late 1950s. This reputation as the “mostuseful” is due to the wide-ranging tasks that

the machine is capable of performing. These

wide-ranging jobs, in turn, demand that

operators have the knowledge, skills, and

experience required for safety and productivity

The first edition of this book, Operating

Techniques for the Tractor-Loader-

Backhoe , published in 1983, was writtensimply as an information source covering

standard machine operations and

procedures. Over the years,

training programs sought it

out for its practical and detailed

information. This Revised Edition

has been greatly expanded to

provide even more detailed information

for operators and training programs, such as:the physics of operation, machine control

guidelines, safety considerations, and

preventing damage to existing utilities.

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