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CATERPILLAR® MINING TRUCK BODIES

Operations and Maintenance Guide

Safety Specifications Operation Maintenance

CATERPILLAR® MINING TRUCK BODIES

Operations and Maintenance Guide

Safety Specifications Operation Maintenance

Caterpillar®

MINING TRUCK BODIES

Congratulations on purchasing a Caterpillar Mining Truck Body: high performance and rock solid! This document provides details necessary for safe, efficient, productive operation with preventive and routine maintenance procedures designed to maximize the life of the body. Your Caterpillar Mining Truck Body is designed to give years of safe, low cost, high performance, maximizing your payload while minimizing your downtime.

Safety: Operating safety is the responsibility of everyone involved. Some of the safety areas to consider while operating the Caterpillar Mining Truck Body are: 1. Proximity To Equipment: Large mining equipment needs a lot of operating room due to limited visibility of the operator. If you can’t see the operator in the mirrors, the operator can’t see you. Never assume the operator knows where you are. Audible and visual communications are a must before entering the work area. When traveling, never follow too closely behind large mining equipment. Large mining equipment always has the right-ofway. Never take chances with large equipment. 2. Crushing Hazard: Any time work is being performed around large mining trucks, the danger of crushing injuries exists: • Carry-back material, stuck in the body, can come loose at any time when the body is in a raised position. Before working on a truck always inspect the body for carryback material and if possible, remove the material before

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working in or around the truck. If it isn’t possible to remove the material, flag off a safe area around the body where material would not hit a person upon leaving the body. • Body prop cables should be used whenever the body is to be left in a raised position. These cables are designed to hold the weight of an empty bed in a raised position. As with all other safety items, the cables should be inspected regularly and replaced if damaged, kinked, loose, or broken strands are visible. Never use anything except the designed cable for the job. • Additional safety materials can be used for blocking the body in a raised position for extended work periods or where additional safety materials are deemed necessary. Cribbing material, timbers, steel beams, etc., can be used to support the bed to prevent crushing injuries. • During normal operation, the body canopy comes in close proximity to the top of the truck cab. Never place yourself between the top of the cab and the canopy while the body is being raised or lowered.

3. Burn Hazard: Exhaust-heated bodies utilize the engine exhaust gases to heat the body and minimize buildup of hauled materials in freezing conditions. The exhaust enters the front wall of the body in two separate locations and these locations can cause burns if they come in contact with unprotected skin. Care should be taken when working in these areas to prevent damaging burns.

Specifications: 1. Identification: Identification plates, located on each of the Caterpillar Mining Truck Bodies, are normally found on the upper front wall just behind the right-hand side of the cab. These plates contain a unique serial number that identifies the body in the Caterpillar network for warranty and product support. 2. Specifications: The Caterpillar Mining Truck Body is a highly technical piece of equipment and has rigorous standards and specifications in its design for each of the body components. Caterpillar uses a Mining Truck System Model

approach for the basis of design and analysis. Caterpillar engineers design the body to be field repairable using conventional welding techniques.

This systems approach to design allows the engineers to take into account the effects of the body on the chassis as well as the chassis on the body with variable input from road and mining conditions. The result is a body that is responsive to the truck system and yields optimum performance with excellent durability.

System Structural Analysis Components of the Mining Truck system

Body and Payload

Power Train

Chassis

Wheels and Tires

Terrain

Suspension

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Operations: Based on the information supplied by the customer in the body profile worksheet, each Caterpillar Mining Truck Body is designed for a target payload by weight which is specified in a unique sales drawing issued for each body. The Caterpillar Mining Truck Body is designed to carry the rated target payload according to the 10/10/20 overload policy (see your Caterpillar representative for details). Following this policy will ensure years of productive and low-cost life. However, in order for this to be effective, proper operations procedures must be practiced. Daily

In order to give the operator a new visual loading reference, the load arrow was implemented. The load arrow represents the center of the volume of the load (center of gravity). The machine operator should center the bucket on the load arrow for each dipper placed in the body. Initially, the loading arrow should be utilized in conjunction with a load study to ensure proper weight distribution since the loading tool and bucket size can affect load distribution. Care should be taken not to load the canopy as it is not designed as a loadbearing structure.

inspections, load placement, discharge height, load management, haul road maintenance, and proper dumping techniques are all critical to the long-term success of these bodies. 1. Daily Inspection: Pre-shift, daily inspections should be performed by the operator prior to beginning work. These inspections should consist of walking around the body and inspecting the understructure for physical damage, cracks, broken welds, and misalignment. Hoist cylinder mounts and pivot pin areas should be checked to ensure that they are in proper working order. The body should be kept as clean as possible to minimize carry-back of materials and reducing the net payload of the body. 2. Load Placement: Load arrows, located on the sidewalls of the body, help guide the operator to center each bucket load as it is placed in the body. Load placement was less of an issue for the older, standard bodies. The loader operator simply centered on the sidewall. In the new lightweight body design the rear corners of the sidewalls were eliminated and the loader operator did not have the same visual reference point to center the load. This often resulted in a forward payload bias which placed more load on the front tires. This forward bias also causes the Caterpillar Vital Information Management System (VIMS) or Truck Payload Management System (TPMS) to report a payload less than actual. MSDII Loading Arrows

Standard Dual Slope

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250 yd 3 MSDII

3. Discharge Height: Body impact damage is one of the life-reducing events in a body’s performance. Material fragementation and discharge height both affect impact damage. Large rocks, dropped too far above the floor, can cause impact damage to the floor plates by causing a yield case or high stress level, greatly reducing component fatigue life. Large rocks should be loaded with care to prevent floor damage. The bucket should not be opened above the top rail of the body when the first bucket is placed in the body. If possible, finer material should be loaded in the first passes and the larger pieces stacked on top of this “bedding” material to absorb some of the loading shock. Once yielded, the floor material weakens and creates pockets between floor ribs or creases over floor rib edges which creates areas prone to accelerated wear. Additionally, significant impact to the floor can damage under floor ribs and rails and shorten the life of the body. 4. Load Management: Proper load management is essential to predictable productivity and budgeting. There are many tools available today designed to help manage the target payloads for each body design. VIMS, TPMS, and scoreboards are a few of the more popular tools used today to help manage payloads and productivity. Proper load placement is essential to accurate weight readings with these systems. The expressed intent of the load arrow is to provide the loader operator with an aid to proper load placement. Because load placement is critical to tire and component life as well as VIMS and TPMS accuracy it is important that the loading tool operator use this aid. Forward biased loads tend to under-report and rearward biased loads tend to over-report. Forward biased loads also negatively

affect front tire life. Not only is the actual payload greater than reported in VIMS, which could exceed the 10/10/20 policy, but a disproportionate share of the overload is being carried by the front tires, resulting in shortened tire life. 5. Racking: The age-old problem! Racking is defined as twisting of the body which puts stress on weld joints and steel plate. It can cause permanent deformation of the body or at least increased fatigue which leads to reduced service life. Nothing does more damage over the long haul than racking due to poor haulage road and dump conditions. Two types of damage can occur in a body: impact and fatigue. Fatigue life is dependent on the magnitude of the stress and the frequency of the occurrence. Haulage road washboards, sharp turns, potholes, road hazards and poor or improper super elevation all contribute to racking of the body. Proper use of motor graders on roads and the use of dump dozers to manage dumping areas and berms can help alleviate this problem. 6. Dumping: Body damage can occur to the rear section of the body (rib area) and to the understructure (rail area) when the body comes in contact with the berm while dumping or leaving the dump area or by raising the tail of the body into an existing pile while dumping on level ground. Both contact damage and increased stress levels can occur. The obvious denting of the body tail structure is evidence that the entire structure is experiencing increased stress due to this operation. The body should be lowered completely before leaving the dump area after dumping over a berm. Not only does this minimize the chance for damage, it also reduces the possibility of lowering the height of the berm where it will have to be repaired. Consistently coming into contact with a berm or pile while dumping causes cumulative stresses to occur in the body understructure. See the results of a stress analysis test below, simulating these stresses.

the body very quickly, causing the body to tip upward by generating a moment at the pivot bore of the body. The force that tips the body works against the dump cylinders and when they reach the end of their cylinder stops the front of the body may actually lift off the ground. Controlled operator dumping techniques can minimize this phenomenon. By slowly raising the body in the dump cycle the load moves more slowly toward the rear of the body. Gravity can then take over and part of the load will have time to shear and break off, reducing the back-end load on the body. This will limit the additional rear weight and minimize liftoff. If you are experiencing any of the above dumping conditions please contact your Caterpillar Product Support representative for help. Sensitivity of dumping into berm High Stress Areas

Berm Contact

Main rail stresses while dumping and contacting a pile or berm No Berm Contact

Hoist Bracket

Ribs

Main Rails

Pivot Bracket

If the material being dumped is highly cohesive in nature, the load may stick together and slide out of the body as a solid unit instead of shearing and leaving the body in pieces. This process is called “loafing,” where the load appears to closely resemble a loaf of bread. This phenomenon can create overcentering of the body as the load moves from the front to the rear of the body. The weight of the load moves the center of gravity of the load to the rear of

Productivity issues can exist on dumps that are too soft and that have berms that can slough. Dozer operators sometimes have to continually push down the dumps and rebuild the berms to maintain safe dumping conditions. In turn, the truck drivers may utilize extra care and spend more time when backing to a berm or spotting. Where these conditions exist and the truck cycle is adversely impacted by longer dumping cycles, productivity may be improved and a safe environment maintained by dumping short and letting the dozer operator push the load over the dump. This minimizes the truck’s exposure to the dump edge and effectively shortens the dump cycle thus improving truck cycle productivity. 5

Body Maintenance Program: In order to maximize the service that you get from your Caterpillar Mining Truck Body, a body maintenance program needs to be developed and followed. Service intervals for the body should follow the same service intervals as the rest of your Caterpillar equipment. Regular body inspections covering primary welds, liner thicknesses, wear bar thicknesses, impact damage, pivot

1. Benchmarking For Wear: Establishing material wear rates for the different areas of the body allows planned maintenance repair schedules and controlled costs. In order to determine wear rates for the different liner plates and base body, original material thicknesses need to be benchmarked and monitored. Ultrasonic measurements will provide this information. Measurements need to be taken in the areas shown, and stored in a spreadsheet similar to the ones shown below. Liners may be fine at half thickness for a wear application but not suitable for a high impact application. Caterpillar MSD Body Wear Measurements

bore wear, and hoist bracket wear are essential in maintaining your body. The Caterpillar Mining Truck Body is a highly technical piece of equipment, engineered to give a high level of performance. With all technical products, maintenance is a key to optimizing the service life.

2. P.M. Inspections: Regular P.M. inspections of the bodies are critical to the service life on the Caterpillar Mining Truck Bodies. Inspections should include critical weld areas, pivot bores, field joints in ribs and rails, liner plates, front wall beams, sidewall top rail sections, rear floor bolsters, and any other areas that might be affected by minespecific applications. Ultrasonic inspections for material thickness of critical liner plates and unprotected base material should be conducted and the results. Planned P.M. hours should be used for routine welding repairs; larger repairs, found in the P.M. process, should be scheduled for planned downtime periods if possible. Contact your dealer for proper weld procedures on MSD bodies. 6

Caterpillar MSD Body Wear Layout Dimensions are approximate and subject to change

3. Liner Replacement: Modular liner packages are available from the factory for replacing worn body liner. Liners, both impact and wear, need to be regularly inspected for effectiveness. Impact liners need to be replaced sooner than wear liners since the impact effectiveness of a thinner plate is much less than a thinner wear surface. A rule of thumb to use for liner replacement is to replace impact liners when the working thickness is 50% or less of the original thickness and wear liners at 90%. If liners are not replaced in a timely manner, damage can occur to base body material which will cost more to repair/replace than the modular liners. 4. Wear Bar and Tumble Bar Replacement: Critical floor and sidewall liners are protected by wear or tumble bars. These bars are designed to protect the critical leading edge welds of the liner plates. Protecting these welds will ensure that the service life for the liner plates is maximized. Failure to maintain these wear bars may result in the leading edge welds being prematurely worn away which will allow material to work its way under the plates and lift the plates away from the truck body. The bars are also thicker than the liner plates which minimizes front edge wear on the plate and helps maximize the plate life. Replace a bar when the bar thickness is equal to or less than the liner plate and the material begins to erode the liner plate weld.

5. Crack Repair: Minor body cracks may appear due to fatigue or impact damage. Timely repairs of these small cracks will prevent larger, more expensive repairs. In general, gouge out the crack, remove all foreign material, and re-weld making sure there is adequate penetration for a competent weld. 6. Body Pivot: The body pivot area is exposed to fatigue due to loading, hauling, and dumping activities. Pivot pin wear is a normal wear process and needs to be monitored. When necessary, the body should be removed from the truck and the pivot bore welded and new bores turned. Proper body shimming will ensure proper body loading and prolong the pivot bore life. 7. Truck Cleanup: Unnecessary buildup of material on the underside of the body and truck chassis reduces available payload and can cause damage to truck and body components. Chassis and bodies should be washed at least each P.M. cycle to remove this material and more often in extreme conditions. This will also help when inspecting bodies for cracks.

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Impact and Wear Solutions Your mining body requirements are as unique as your mine. Caterpillar offers a variety of Mine Specific liner and wear package options to protect the body structure from impact and wear.

Rear Third Options (Area 13) The rear third of the body needs more protection since all of the material passes this point before exiting the body. In addition to the smooth plate options for the front two-thirds of the body, the rear third has four additional optional liner packages. These options include smooth plate, rock box, zipper grid, and MAWPS (Mechanically Attached Wear Plate System). These patented Caterpillar designs provide optimum protection in all mining conditions.

Body Liner Options Caterpillar offers 14 different modular liner plate packages for additional impact and wear protection in the body. They can be configured to meet the entire range of impact and wear needs.

1

1 2

1

2

Smooth Plate

Zipper Grid

Smooth Plate is recommended for cohesive materials to reduce material build-up and carry-back.

U.S. PATENTS: 6,174,014 and 6,305,731

5

6

14

4

3

4

4

3

4

9

10

9

11

12

11

The Zipper Grid is a cross between a rock box and smooth plate and is well suited to semi-cohesive materials in that it has some sliding action to avoid build-up and carry-back 5 14

8

8

7

7

Rock Box

MAWPS

U.S. PATENT: 6,129,409

The Rock Box is well suited to dry and non-cohesive materials. The grids fill with hauled material thus causing the payload to tumble during dumping, wearing on itself and not the steel.

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U.S. PATENTS: 5,937,549 and 6,194,080

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Our replaceable wear plate system comes in solid plate and skeletal plate. Individual MAWPS replacement requires no welding and can be done in minutes.

BODY LINER OPTION LOCATIONS

As the interface between your truck and your payload, the body is vital to your bottom line – cost per ton. The Caterpillar Mining Truck body system achieves a new level of productivity with a balanced combination of excellent payload, performance, and durability. The same expertise that engineered the Caterpillar Mining Truck body is available to help you maintain your productivity. The Caterpillar dealer

network, with more than 1600 outlets around the world, will keep you running with service you need when you need it. Caterpillar Mining Truck bodies are available for new chassis orders and for replacement requirements. To learn more about the Caterpillar Mining Truck body and what it can do for your operation, call your Cat dealer today.

The preceding discussion on operations and maintenance of Caterpillar Mining Truck Bodies is a recommended guide for most mining sites. Your site may require unique support. Contact your dealer representative to give you the help that you need.

AEDK0627

www.CAT.com

©2004 Caterpillar All rights reserved. Printed in U.S.A.