40106 20 Force SCREW (M6 x 20)

Introduction
This special instruction covers the procedure to rework the engine end frame on the above AD60 Underground Articulated Trucks. This supplemental product support literature should be used with the appropriate Service Manual and the appropriate Parts Manual that is available for this standard machine.Read the entire Special Instruction. Understand the information before you perform any procedures. Understand the information before you order any parts.ReferenceService Manual, RENR8595, "Machining and Welding Information for Underground Articulated Trucks".ReferenceDisassembly and Assembly, UENR2741, "AD60 Underground Articulated Truck Machine Systems".Safety Section
Work safely. Most accidents that involve product operation, maintenance, and repair are caused by failure to observe basic safety rules or precautions. An accident can often be avoided by recognizing potentially hazardous situations before an accident occurs. A person must be alert to potential hazards. This person should also have the necessary training, skills, and tools in order to perform these functions properly. Safety precautions and warnings are provided in this instruction and on the product. If these hazard warnings are not heeded, bodily injury or death could occur to you or to other persons. Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard. Therefore, the warnings in this publication and the warnings that are on the product are not all inclusive. Ensure that all personnel are safe when using a tool, procedure, work method, or operating technique not recommended by Caterpillar. Ensure that the product will not be damaged or the product made unsafe by the operation, lubrication, maintenance, or the repair procedures that are used.
Personal injury or death can result from machine articulation or movement. Machine frames can move and a person can be crushed. Connect the steering frame lock between the front and rear frames before working on the machine.Before operating the machine, place the steering frame lock in the stored position.Failure to place the steering frame lock into the stored position before operating can result in loss of steering.
Personal injury can result from flame cutting or welding on painted areas.The effect of gasses from burned paint is a hazard to the person doing the cutting or welding.Do not flame cut or weld on painted areas.
Personal injury or death can result from fumes, gases and ultraviolet rays from the weld arc.Welding can cause fumes, burn skin and produce ultraviolet rays.Keep your head out of the fumes. Use ventilation, exhaust at the arc, or both, to keep fumes and gases from your breathing area. Wear eye, ear and body protection before working.Protect yourself and others; read and understand this warning. Fumes and gases can be dangerous to your health. Ultraviolet rays from the weld arc can injure eyes and burn skin. Electric shock can cause death.Read and understand the manufacturer's instructions and your employer's safety practices. Do not touch live electrical parts.See "American National Standard Z49.1, Safety in Welding and Cutting" published by the American Welding Society.American Welding Society
2501 N.W. 7th Street
Miami, Florida 33125
See "OSHA Safety and Health Standards, 29 CFR 1910", available from U.S. Department of Labor.U.S. Department of Labor
Washington, D.C. 20210
Machine Preparation
Note: Cleanliness is an important factor. Before the removal procedure, clean the exterior of the component thoroughly. Cleaning the exterior will help to prevent dirt from entering the internal mechanism.
Move the machine to a hard level surface away from operating machines and away from personnel.
Engage the parking brake. Place wheel blocks in front of the wheels and behind the wheels.
Stop the engine.
Connect the steering frame lock. Refer to Disassembly and Assembly, "Steering Frame Lock - Separate and Connect".
Turn the key start switch and the battery disconnect switch to the OFF position. If there is no battery disconnect switch, remove the negative battery cable at the battery.
Release system pressure. Refer to Disassembly and Assembly, "System Pressure - Release".Procedure to Rework the Engine End Frame
This procedure provides information to rework one side of the engine end frame. The procedure to rework the other side of the engine end frame is identical.Note: For welding repairs performed on Caterpillar Underground machines using Manual Metal Arc Welding (MMAW), use AWS E7016 electrodes for the first three passes. Use AWS E7018 electrodes for the remaining passes of the welding repair.Note: For all welding repairs performed on Caterpillar Underground machines using Gas Metal Arc Welding (GMAW) use AWS ER70S-6 wire.
Illustration 1 g03861461
View of the engine end frame
Remove machine components in order to access the repair area. Ensure that vulnerable machine components are protected during the welding process.
Remove all paint, rust, grease, and dirt from the surfaces to be welded.Note: Welds on painted or dirty areas can cause welds of poor quality. The result is weld embrittlement from hydrogen, porosity, or lack of fusion.
Use an air carbon arc torch or use a grinder in order to remove the crack completely. Use the dye penetrant to inspect the gouged area in order to ensure that the crack has been removed.
Clean the weld area in order to remove all carbon deposits, slag, and dye penetrant.
Preheat the repair area prior to welding. Refer to Service Manual, "Preheat, Interpass, and Heat Input".
Fill the gouged out area with weld.
Use the dye penetrant or the magnetic inspection process in order to check and make sure that the crack is removed.
Illustration 2 g03870940
View of the right side of the engine end frame (1) Suspension mount (2) Plate
Weld suspension mount (1). Refer to Illustration 2 and Table 1.
Weld plate (2). Refer to Illustration 2 and Table 1.
Fill with weld and ensure a smooth transition between suspension mount (1) and plate (2). Refer to Illustration 2 and Table 1.
Table 1
Item     Dimension    
W1     A>B 15 mm (0.60 inch) Fillet weld    
W2    
12 mm (0.50 inch) Fillet weld