- Off-Highway Truck/Tractor:
- 797 (S/N: 5YW1-UP)
- 797B (S/N: JSM1-UP)
- 797F (S/N: LAJ1-UP; WSP1-UP)
- 797B (S/N: JSM1-UP)
Introduction
This Special Instruction provides the necessary information in order to rework bores on 797, 797B, and 797F off-highway truck frames, bodies and axle housings. Each repair will be unique. You may need to modify the procedures in some situations.
Read this entire Special Instruction. Read all of the reference documents which are listed below. Do not perform any procedure in this publication until you understand the information that is contained within this publication.
ReferenceSpecial Instruction, REHS0541, "Procedure For the Inspection, Repair, and Component Replacement On the Frames of Off-Highway Truck/Tractor "
ReferenceSpecial Instruction, REHS0744, "Inspection of the 797 and 797B Of-Highway Truck Frame and the Rear Axle Housing"
ReferenceService Bulletin, SEBF8879, "Repair/Replace Large OHT Body Pivot Bores and Suspension Bores"
ReferenceOperating Manual, NEHS0665, "1U-9600 Welding Group Tool Operating Manual"
ReferenceSpecial Instruction, SEHS8985, "1U-8660 Boring Bar Special Instruction"
ReferenceANSI, Specification D1.1
ReferenceANSI, Specification D14.3
Information
Important Safety Information
The following information is an explanation of various labels that are found in this document.
Warnings
The warning label informs the technician that an injury or death can occur as a result of a condition that may exist.
Notices
A notice informs the technician that component damage can occur as a result of a condition that exists.
Notes
A note contains general information for the technician about the operation that is being performed.
Proper repair is important to the safe operation and the reliable operation of this machine. This document outlines basic recommended procedures. Some of the procedures require special tools, devices, or work methods.
Before you perform any repairs or before you perform any maintenance, read all safety information. Understand all safety information before you perform any repairs or before you perform any maintenance.
Safety information is provided in this document and on the machine. If these hazard warnings are not heeded, bodily injury or death could occur to you or other persons.
The "Safety Alert Symbol" that is followed by a "Signal Word" identifies a hazard. "DANGER", "WARNING", and "CAUTION" are "Signal Words".
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| Illustration 1 | g00008666 |
The signal word "WARNING" has the following meanings:
- Pay Attention !
- Become Alert !
- Your Safety Is Involved !
The message that appears under the safety alert symbol explains the hazard.
Operations or conditions that may cause product damage are identified by "NOTICE" labels on the machine and in the service information.
The person that services the machine may be unfamiliar with many of the systems on the machine. Use caution when you perform service work. Special knowledge of the systems and of the components is important. Before you remove any component or before you disassemble any component, obtain knowledge of the system and knowledge of the component.
Caterpillar cannot anticipate every possible circumstance that might involve a potential hazard. The safety information in this document and the safety information on the machine are not all inclusive. You must determine that the tools, procedures, work methods, and operating techniques are safe. You must determine that the operation, lubrication, maintenance, and repair procedures will not damage the machine. Also, you must determine that the operation, lubrication, maintenance, and repair procedures will not make the machine unsafe.
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Improper operation, lubrication, maintenance or repair of this product can be dangerous and could result in injury or death. Do not operate or perform any lubrication, maintenance or repair on this product, until you have read and understood the operation, lubrication, maintenance and repair information. |
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Personal injury can result from not following the specified procedure. To avoid personal injury, follow the procedure as specified. |
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Personal injury or death can result from improper lifting or blocking. When a hoist or jack is used to lift any part or component, stand clear of the area. Be sure the hoist or jack has the correct capacity to lift a component. Install blocks or stands before performance of any work under a heavy component. Approximate weights of the components are shown. Clean all surfaces where parts are to be installed. |
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| NOTICE |
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Do not allow any dirt or foreign material to get into the hydraulic system during assembly, connection of lines, when components are filled with fluid, or during any maintenance operation. |
| NOTICE |
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Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to Special Publication, NENG2500, "Dealer Service Tool Catalog" for tools and supplies suitable to collect and contain fluids on Cat products. Dispose of all fluids according to local regulations and mandates. |
Basic Precautions
Always observe the list of basic precautions that follows:
Safety Signs
Safety signs include the items that follow: signs, information plates and decals. Read all "Safety" signs on the machine before operating, lubricating, or repairing the machine. Understand all "Safety" signs on the machine before operating, lubricating, or repairing the machine. Replace any safety signs that are in the conditions that follow: damage, unreadable and missing.
Protective Equipment
When you work around the machine, always wear protective equipment that is required by the job conditions. Protective equipment includes the items that follow: hard hat, protective glasses and protective shoes. In particular, wear protective glasses when you use a hammer or when you use a sledge hammer. When you weld, the appropriate protective equipment is required by the job conditions. Protective equipment for welding includes the items that follow: gloves, welding hood, goggles and apron. Do not wear loose clothing or jewelry that can catch on parts of the machine.
Mounting and Dismounting
Use steps and handholds when you mount a machine. Also, use steps and handholds when you dismount a machine. Before you mount the machine, clean any mud or debris from steps, walkways, or work platforms. Always face the machine when you use steps, handholds, and walkways. When you cannot use the accesses on the machine, use ladders, scaffolds, or work platforms to perform safe repair operations.
Hot Fluids and Parts
To avoid burns, be alert for hot parts on machines which have just been stopped and hot fluids in lines, tubes and compartments.
Be careful when you remove filler caps, breathers, and plugs on the machine. Hold a rag over the cap or plug in order to prevent being sprayed by pressurized liquids. When the machine has just been stopped, the danger of hot fluids is greater.
Corrosion Inhibitor
Corrosion inhibitor contains alkali. Avoid contact with the eyes. Do not allow corrosion inhibitor to contact the skin for extended periods of time. Avoid repeated contact with the skin. Do not drink corrosion inhibitor. In case of contact, immediately wash skin with soap and water. For contact with the eyes, flush the eyes with large amounts of water for at least 15 minutes. Seek medical attention.
Batteries
Do not smoke when an inspection of the battery electrolyte level is made. Never disconnect any charging unit circuit or battery circuit cable from the battery when the charging unit is operating. A spark can cause an explosion from the flammable vapor mixture of hydrogen and oxygen that is released from the electrolyte through the battery outlets. Do not allow battery electrolyte to make contact with the skin or with the eyes. Battery electrolyte is an acid. In case of contact with battery electrolyte, immediately wash the skin with soap and water. For contact with the eyes, flush the eyes with large amounts of water for at least 15 minutes. Seek medical attention.
Pressurized Items
- Always use a board or a piece of cardboard when you check for a leak. Leaking fluid under pressure can penetrate body tissue. Fluid penetration can cause serious injury and possible death. A pin hole leak can cause severe injury. If fluid is injected into your skin, you must get treatment immediately. Seek treatment from a doctor that is familiar with this type of injury.
- Relieve all pressure in air, oil, or water systems before any lines, fittings, or related items are disconnected or removed. Always make sure that all raised components are blocked correctly. Be alert for possible pressure when you disconnect any device from a system that utilizes pressure.
- Fuel lines that are damaged and fuel lines that are loose can cause fires. Lubrication lines that are damaged and lubrication lines that are loose can cause fires. Hydraulic lines, tubes, and hoses that are damaged can cause fires. Loose hydraulic lines, tubes, and hoses can cause fires. Do not bend or strike high-pressure lines. Do not install lines which have been bent or damaged. Check lines, tubes, and hoses carefully. Do not use your bare hand to check for leaks. If fluids are injected into your skin, you must get treatment immediately. Seek treatment from a doctor that is familiar with this type of injury.
- Pressure air or water can cause personal injury. When pressure air or water is used for cleaning, wear a protective face shield, protective clothing, and protective shoes. The maximum air pressure for cleaning purposes must be below 205 kPa (30 psi). When you use a pressure washer, keep in mind that the nozzle pressures are very high. The nozzle pressures are frequently above 13790 kPa (2000 psi). Follow all of the recommended practices that are provided by the manufacturer of the pressure washer.
Location of Parts
The location of the repairable parts follows:
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| Illustration 2 | g01086895 |
Truck frame (1) Lower bores for the suspension of the frame (2) Upper bores for the suspension of the frame (3) Bores for the pivot of the truck body (4) Bores for the suspension of the frame | |
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| Illustration 3 | g01087339 |
Truck body (5) Bores for the hoist cylinders (6) Bores for the pivot | |
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| Illustration 4 | g01090171 |
Axle housing (7) Front, upper bores for the suspension (8) Front, lower bores for the suspension (9) Rear bores for the suspension | |
Chains and Cables
Use approved cables, chains, and lifting devices in order to lift components. Refer to the manufacturer's weight's in order to determine the application when you select the following items: cable, chain and lifting devices. When you lift a component, the lift angle is critical. Refer to the Illustration that follows in order to see the effect of the lift angle on the working load limit.
Note: The lifting devices that are shown in this publication are not Caterpillar parts.
Note: Ensure that the hooks are equipped with a safety latch. Do not place a side load on the lifting eyes during a lifting operation.
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| Illustration 5 | g01104561 |
Lift angles for lifting slings. | |
| Lift Angles For Lifting Slings | |
| Callout | Description |
| (10) | The load capacity is 50% of the working load limit for the sling. |
| (11) | The load capacity is 70% of the working load limit for the sling. |
| (12) | The load capacity is 86% of the working load limit for the sling. |
| (13) | The load capacity is 100% of the working load limit for the sling. |
Required Tooling
| Required Tooling | ||
| Qty | Description | Part Number |
| 1 | Automatic Welding Group | 1U-9600 |
| 1 | Hydraulic Boring Bar | 1U-8660 |
| 1 | Infrared Thermometer | 164-3310 or 192-3750 |
| Leveling and Measuring Tools | ||
| Cleaning Equipment for Metal Surfaces | ||
| Equipment for Welding Frame | ||
| 1 | Wire Feeder | 161-6202 |
Although equivalent equipment may be used, the 1U-8660 Hydraulic Boring Bar and the 1U-9600 Welding Group have a number of advantages. With these groups, the same bar is used for welding and boring operations. The bar is also used to remachine the faces at the ends of the bores.
Power supplies for the hydraulic bar drive are available for use in the shop or on-site use. Units in the shop can be wired for electrical service anywhere in the world. Regardless of the equipment that is used, read the operation manuals and understand the operation manuals, and the welding instructions that are given in Special Instruction, REHS0744, "Inspection of the 797 and 797B Of-Highway Truck Frame and the Rear Axle Housing".
Dealer Service Tools has complete information on the welding and boring tool groups, and on required equipment and optional equipment. The hotline numbers for Dealer Service Tools are (800) 541-8665 in Illinois,, (800) 542-8665 elsewhere in the USA, and, (800) 523-8665 in Canada. The fax number is, (309) 494-1475.
Preparation
Preparation of the Work Site
- Before you start to work on the machine, disconnect the battery. Attach a "Do Not Operate" tag in the operator compartment.
- When possible, make all repairs with the machine parked on a level, hard surface. When you work on the machine or when you work under the machine, block the machine in order to prevent the machine from rolling. Select an appropriate site in order to repair the chassis. Select an area that is flat, smooth, and well drained. Make sure that there is sufficient space for the items that follow: machine, components, tools and lifting devices.
- Do not work on any machine that is supported only by lift jacks or a hoist. Always use hardwood blocks or jack stands to support the machine before performing any service or disassembly. Always make sure that the maximum load capacity of the jack stands is greater than the weight of the machine.
- Make sure that the work area around the machine is made safe. Become aware of hazardous conditions that may exist. If an engine is started inside an enclosure, make sure that the engine exhaust is properly vented.
- Before you start a repair, be sure that all protective devices are properly installed and that all protective devices function correctly. When a guard must be removed or a shield must be removed in order to perform the repair work, use extra caution.
- Always use tools that are in good condition. Before you perform any service work, understand the intended use of the tools.
- Replace all fasteners with fasteners of the same part number. Do not use a lesser quality fastener if replacements are necessary.
- Prepare to stop an engine that has had a recent overhaul. Prepare to stop an engine that has a fuel system that has recently been worked on. If the engine has not been assembled correctly, the engine can possibly overspeed. If the fuel settings are not correct, the engine can possibly overspeed. Overspeeding can cause bodily injury, death, or property damage. Prepare to shut off the fuel and the air supply to the engine in order to stop the engine.
- Be careful when you remove cover plates. Gradually back off the last two bolts or the last two nuts that are located at opposite sides of the cover or the device. Pry the cover loose in order to relieve any spring or other pressure, before you completely remove the last two bolts or the last two nuts.
- When you make repairs that require welding, have appropriate reference information. Welding should only be performed by personnel that are adequately trained. Personnel should be knowledgeable in welding procedures. Make sure that all repairs that require welding comply with the ANSI/AWS standards.
- Do not damage wiring during removal operations. When you install the wiring, do not damage the wiring. The wiring can be damaged in operation by the conditions that follow: contact with sharp corners, rubbing against objects and contact with hot surfaces. Do not connect the wiring to a line that contains fluid.
- Tighten connections to the correct torque. Make sure that all heat shields, clamps, and guards are installed correctly in order to avoid excessive heat, vibration, or rubbing against other parts during operation. Shields that protect against oil spray onto hot exhaust components in the event of a line, tube, or seal failure must be installed correctly.
- Do not operate a machine if any rotating part is damaged or if any rotating part contacts any other part during operation. Any high speed rotating component that has been damaged or altered should be checked for balance before reusing. Before you start the engine, make sure that all protective devices are properly installed. Before you operate the machine, make sure that all protective devices are functioning correctly.
- Use extra caution when you service the rubber belts. Follow all safety instructions in the appropriate manuals. Wear protective glasses. Block the machine in order to prevent the machine from moving.
- When you unload components, place the components near the machine. Leave enough space around the machine in order to maneuver lifting devices. Carefully inspect the parts. Ensure that all parts are undamaged. Organize the parts for assembly.
- The repair of the chassis will be easier if the machine is clean. Use a steam cleaner to clean the truck. Be careful with the steam cleaner. Do not damage electrical wiring or cab windows.
Prepare the Area for Welding
Clean the area that will be welded. Make sure that the substances that follow are removed from the area that will be welded.
- Oil
- Grease
- Paint
- Dirt
If the temperature of the base metal is below 21 °C (70 °F), heat the base metal to a temperature of at least 21 °C (70 °F). Maintain the temperature of the base metal at 21 °C (70 °F) during the welding process.
Note: Heat distortion of the base metal is possible when you weld. Avoid excessive heating of the base metal. A maximum interpass temperature of 260 °C (500 °F) should be observed.
Attach the welding ground cable directly to the base metal. Protect machined surfaces from sparks. Protect the machined surfaces from the weld splatter.
Initial Work
Before the repair work begins perform a detailed inspection. Refer to Special Instruction, REHS0744.
Inspections of the frame assembly for cracks should be conducted during regular maintenance intervals. Some of the areas that need to be inspected are blocked by one or more components. If the component that is blocking the frame is removed, an inspection of that area should be performed. It is therefore important to take advantage of the opportunity to inspect those parts of the frame assembly that are exposed whenever components are removed.
When you need to remove components in order to repair the frame, refer to the appropriate Disassembly and Assembly Manual.
Contact the subsidiary service engineer, the plant service engineer, or the plant product analyst for additional information that is regarding repairs for the frame that are not covered in this Special Instruction.
Bore Bar
Before building up the bore surface with the welder, the boring bar must be used to remove all corrosion, pits, smeared bearing material, and other debris from the bore surface. The boring prevents contamination of the weld and the boring brings the bore back to true cylindrical shape. Although the location of the bar for a cleanup operation is not as critical as locating the bar for bore finishing, it is best for the bar to be located at the centerline specifications. Locating the bar at the centerline specifications is done in order to minimize the amount of weld that is needed. Locating the bar at the centerline specifications is also done in order to prepare for finish operations.
Use a power washer or abrasive equipment such as a grinder in order to smooth the surfaces, as needed. Always wear a face shield and protective clothing during this work.
Continue by following Special Instruction, SEHS8985, "1U-8660 Boring Bar Special Instruction" (or the instructions for your unit) for preliminary setup of the boring bar in the bores. Allow space at the center of the boring bar for a carpenter's level, and space at one end of the bar for the cutter for boring. Place three bearings for the boring bar on the bar between the supports, so one can be secured in place at the center of the bar in order to provide support for the bar during boring. The centering cones and stop collars may be used initially in order to center the bar in the bore of the pivot, but positioning adjustments may be necessary.
Tack weld the bar support bearing at the center of the bar in order to ensure that the setup for the boring bar is rigid. Install the boring head. Bore the worn diameter enough to remove all corrosion, smeared material from the bushing, and pits from the surface.
The bores must not be built up by welding until the boring bar has been used to remove all foreign material from the bore surfaces.
Before welding the bores, check the bore surfaces again in order to make sure that the bores are clean. Dirt, moisture, or other foreign material can cause contamination or porosity in the weld.
Bore Weld
Preheat the area that will be welded to approximately 38° C (100° F). Continue to heat the surface in order to maintain the preheat temperature during welding, if necessary. Preheating is a good method for removing any moisture condensation from the surfaces.
After bore clean-up, set up the bore welder following Operating Manual, NEHS0665, "1U-9600 Welding Group Tool Operating Manual", or the instructions for your welder. Follow the specifications for welding that are given in Special Instruction, REHS054, "Procedure For the Inspection, Repair, and Component Replacement On the Frames of Off-Highway Truck/Tractor ". Be sure that no oil or no other substance has contaminated the bore surfaces before starting the welder. Preheating of the base metal is a good way to ensure that no condensation is present on the bore surfaces. Use an infrared thermometer in order to monitor the temperature while you are heating the base metal to approximately 38° C (100° F).
As needed, weld with additional passes in order to provide sufficient stock in order to restore the original bore diameter. Use a deburring tool between weld passes in order to remove any slag from the welded surface. Allow the base metal to cool if the temperature of the base metal rises above the range of 230° to 260°C (450° to 500°F). Extend the weld bead in order to provide sufficient machining stock in order to restore the counterbores and chamfers. Use a manual welding process in order to fill any craters at the starting and the stopping of the welds.
Procedure To Perform Weld Repairs
Weld Specifications and Qualifications
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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 kill. Read and understand the manufacturer's instruction and your employer's safety practices. Keep your head out of the fumes. Use ventilation, exhaust at the arc, or both, to keep fumes and gases from your breathing zone and the general area. Wear correct eye, ear and body protection. Do not touch live electric parts. Refer to the American National Standard Z49.1, "Safety in Welding and Cutting" published by the American Welding Society, 2501 N.W. 7th Street, Miami, Florida 33125: OSHA Safety and Health Standards, 29 CFR 1910, available from U.S. Dept. of Labor, Washington D.C. 20210. |
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Welders must be qualified for fillet welding and groove welding. The welder must be qualified in different welding angles. The angles are vertical, horizontal, etc. The welders should be qualified in the use of the welding processes that follow: Shielded Metal Arc Welding (SMAW), Flux Cored Arc Welding (FCAW) and Gas Metal Arc Welding (GMAW). Refer to ISO 9606 or "American National Standards Institute (ANSI)/American Welding Society (AWS) Specification D1.1, or Specification D14.3" for information that regards the qualifications for the processes that follow: SMAW process, FCAW process and GMAW process. The welders must have used the process at some time within the last six months. The welders must complete the process of certification if the welders have not used the welding processes for six months.
General Weld Repair
Do not use stick electrodes for welding the bore. The use of "E71T-1" wire of 1.3 mm (0.052 inch) is recommended for restoration of metal to the bore. "E7018" stick electrodes may be used for support assembly or component replacement, crack repair, or tack welding of bracing for the boring bar.
- Remove any components that prevent access to the cracked weld.
- Remove all oil, grease, and dirt from the weld area.
- Use the liquid dye penetrant or magnetic particle inspection in order to inspect the entire area for possible cracks.
- Protect machined surfaces from sparks and weld deposits.
- Use an air carbon arc torch or use a grinder in order to remove cracks. Use a grinder to remove cracks that extend through the castings. Remove at least 50.8 mm (2.0 inch) of material past each end of the crack. When the crack is removed, the bottom of the groove should have an angle of 90 degrees in order to ensure sufficient penetration. The side walls of the groove should extend upward at an angle of 45 degrees.
- Use the liquid dye penetrant or magnetic particle inspection to inspect the gouged area in order to ensure that the crack has been removed. Be sure to clean the prepared groove before welding.
- Repair the prepared groove by using passes that do not exceed two times the electrode diameter. If the alternate welding process is selected, the size of the weld pass should not exceed 7.88 mm (0.31 inch) of the volume of the fillet weld. Remove the slag after each weld pass in order to avoid the possibility of slag inclusions.
- Clean the weld area. Inspect the area that was welded. The weld should be free from cracks, porosity, undercut, and incomplete fusion. All weld quality shall conform to ANSI/AWS 14.3 or ISO 6520.
Proper Welding Procedure on Machines and Engines with Electronic Controls
Proper precautions are necessary to prevent damage to electronic controls. When you weld on a machine with electronic controls, use the steps that follow:
- Turn off the engine. Put the key start switch in the OFF position.
- If the machine has a battery disconnect switch, open the switch. If the machine does not have a battery disconnect switch, disconnect the negative battery cable at the battery.
- Connect the ground cable for the welder directly to the actual machine component that will be welded. Place the clamp for the ground cable as close as possible to the welding area. This will reduce the chance of damage from welding current to the components that follow: bearings, hydraulic components and electrical components.
Note: Do NOT use electrical components as a ground point for the welder. Do NOT use ground points for electronic components as a ground point for the welder. Do NOT use hoses as a ground point for the welder. Do NOT use the ground pole on the batteries as a ground point for the welder.
- Protect the wiring harnesses from the weld splatter.
Welding Electrode Specifications
Low Hydrogen Electrodes for the SMAW Process
The tables that follow list the mechanical properties of welds that are deposited by low hydrogen electrodes.
| Mechanical Properties of Welds from Low Hydrogen Electrodes That Are Classified as "ANSI/AWS A5.1 E7018" | |
|---|---|
| Tensile Strength | 480 MPa (69618 psi) |
| Yield Strength | 400 MPa (58015 psi) |
| Elongation | 25% |
| Impact Toughness | 27 J @ -46 °C (20 ft lb @ -50 °F) |
Low hydrogen electrodes must be stored in an electrode oven at 120 °C (250 °F). If low hydrogen electrodes get damp, scrap the low hydrogen electrodes or recondition the low hydrogen electrodes to the manufacturer's specifications.
The table that follows shows setting for the welding current for the electrode diameter.
| Welding Current for Low Hydrogen Electrodes | |
|---|---|
| Diameter | Amperage Rating |
3.2 mm (.125 inch) |
115-165 |
4.0 mm (.157 inch) |
150-220 |
4.8 mm (.189 inch) |
2600-275 |
Use a polarity setting of DC reverse polarity. Remove the slag after each pass of the welding electrode. The width of the weld should not exceed two times the electrode diameter.
Flux Cored Welding Electrode for the FCAW Process
The table that follows lists the mechanical properties of welds that are deposited by the flux cored welding electrode.
| Mechanical Properties from Flux Cored Welding Electrodes That Are Classified as "ANSI/AWS A5.20 E71T-1" | |
|---|---|
| Tensile Strength | 480 MPa (69618 psi) |
| Yield Strength | 400 MPa (58015 psi) |
| Elongation | 22% |
| Reduction of Area | 18% |
| Impact Toughness | 27 J @ -18 °C (20 ft lb @ -0 °F) |
The table that follows shows setting for the welding current for the flux cored welding electrode that has a diameter of 1.3 mm (.052 inch).
| Welding Current for Flux Cored Welding Electrode That Is Classified as "ANSI/AWS A5.20 E71T-1" | ||
|---|---|---|
| Wire Feed Rate | Voltage | Amperage |
| Minimum 5080 mm (200 inch) Per Minute |
24 | 210 |
| Optimum 6985 mm (275 inch) Per Minute |
28 | 250 |
| Maximum 8255 mm (325 inch) Per Minute |
29 | 300 |
Note: The settings for the welding current can vary due to the position of the weld. Also, the settings for the welding current can vary with the manufacturer of the welding electrode.
Use a polarity setting of DC reverse polarity. Remove the slag after each pass of the welding electrode. The fast freezing characteristics of flux cored welding electrode increases the possibility of evolving gas that is trapped in the weld. Control the size of the weld in order to reduce the possibility of evolving gas that is trapped in the weld. The volume of the fillet weld should not exceed 8.0 mm (.315 inch).
Arc Welding Electrodes for the GMAW Process
The table that follows lists the mechanical properties of welds that are deposited by the GMAW Process.
The welding parameters will vary with the position of the weld and with different electrode manufacturers.
Weld Inspection
The weld should not have any of the conditions that follow:
- Cracks
- Porosity
- Undercut
- Incomplete Fusion
In order to verify the quality of the weld, refer to"American National Standards Institute (ANSI) / American Welding Society (AWS) Specification D14.3" and ISO 6520.
Bore Finishing
Set up the boring bar and run rough cuts of the bore. If there is chatter during the cutting operation, the chatter is likely the result of a bore setup that is not rigid. The chatter can also be an unsupported distance between the bearings that stabilize the boring bar. Be sure to eliminate chatter before performing the final bore. Machine the bore to the specified diameter. Machine the faces. Next, machine the chamfer. Finally, machine the details for the counterbore.
Procedure to Rework the Rear Support
Assembly Steps
- Perform weld buildup of the bores of the rear support in accordance with this Service Instruction section entitled ""Procedure To Perform Weld Repairs" " and Corporate Product and Process Specification, "IE0099E".
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| Illustration 6 | g01086895 |
Truck frame (1) Lower bores for the suspension of the frame (2) Upper bores for the suspension of the frame (3) Bores for the pivot of the truck body (4) Bores for the suspension of the frame | |
- Perform machining repairs to the bores for the rear support in accordance with the ""Bore Finishing" " section and the ""Rear Support Component Dimensions" " section.
Rear Support Component Dimensions
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| Illustration 7 | g01089221 |
Rear Support (1) Bores for the pivot of the truck body (2) Bores for the suspension of the frame | |
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| Illustration 8 | g01165995 |
(S/N: 5YW1-237) Rear view A-A (A) 2554.0 ± .3 mm (100.55 ± 0.01 inch) (B) 224 ± 0.5 mm (8.81 ± 0.02 inch) (C) 8.70 ± 0.07 mm (0.343 ± 0.003 inch) Diameter hole, 1/8-27 NPFT thd, two holes (D) "H" surface finish (E) 185.6 ± 0.3 mm (7.31 ± 0.01 inch) (F) 105.5 ± 0.5 mm (4.15 ± 0.02 inch) (G) 105.5 ± 0.5 mm (4.15 ± 0.02 inch) (H) 2183.0 ± 0.5 mm (85.94 ± 0.02 inch) | |
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| Illustration 9 | g01126002 |
(S/N: 5YW238-UP) (S/N: JSM1-UP) (S/N: LAJ1-UP) (S/N: WSP1-UP) Rear view A-A (A) 2554.0 ± .3 mm (100.55 ± 0.01 inch) (B) 224 ± 0.5 mm (8.81 ± 0.02 inch) (C) 8.70 ± 0.07 mm (0.343 ± 0.003 inch) Diameter hole, 1/8-27 NPFT thd, two holes (D) "H" surface finish (E) 196.6 ± 0.3 mm (7.74 ± 0.01 inch) (F) 105.5 ± 0.5 mm (4.15 ± 0.02 inch) (G) 105.5 ± 0.5 mm (4.15 ± 0.02 inch) (H) 2183.0 ± 0.5 mm (85.94 ± 0.02 inch) | |
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| Illustration 10 | g01166002 |
(S/N: 5YW1-237) Left side view B-B (J) 200.0 ± 0.5 mm (7.90 ± 0.02 inch) (K) 170.000 ± 0.065 mm (6.6929 ± 0.0026 inch) diameter, four holes in line, "F" surface finish, (L) 3.0 ± 0.5 mm (0.12 ± 0.02 inch) X 30° chamfer, 4 places. (M) 200.0 ± 0.5 mm (7.8740 ± 0.0197 inch) (N) 701.5 ± 0.5 mm (27.62 ± 0.02 inch) (P) 93.2 ± 0.5 mm (3.67 ± 0.02 inch) (Q) 167.68 ± 0.05 mm (6.602 ± 0.002 inch) diameter, four holes in line, "F" surface finish, see note (R) 3.0 ± 0.5 mm (0.12 ± 0.02 inch) X 30° chamfer, 4 places. | |
 | |
| Illustration 11 | g01126005 |
(S/N: 5YW238-UP) (S/N: JSM1-UP) Left side view B-B (J) 200.0 ± 0.5 mm (7.90 ± 0.02 inch) (K) 170.000 ± 0.065 mm (6.6929 ± 0.0026 inch) diameter, four holes in line, "F" surface finish, (L) 3.0 ± 0.5 mm (0.12 ± 0.02 inch) X 30° chamfer, 4 places. (M) 200.0 ± 0.5 mm (7.8740 ± 0.0197 inch) (N) 701.5 ± 0.5 mm (27.62 ± 0.02 inch) (P) 93.2 ± 0.5 mm (3.67 ± 0.02 inch) (Q) 179.68 ± 0.05 mm (7.074 ± 0.002 inch) diameter, four holes in line, "F" surface finish, see note (R) 3.0 ± 0.5 mm (0.12 ± 0.02 inch) X 30° chamfer, 4 places. | |
Note: Each mating pair of bores must be in-line within a zone 0.8 mm (0.032 inch) diameter. The right-hand pair of bores must be in line with the left-hand pair of bores within zone 2 mm (0.08 inch) diameter.
Procedure to Rework the Center Support
Assembly Steps
- Perform weld buildup of the rear support bores in accordance with this Service Instruction section titled ""Procedure To Perform Weld Repairs" " and Corporate Product and Process Specification, "IE0099A".
- Perform machining repairs to the rear support bores in accordance with this Service Instruction section titled ""Bore Finishing" " to the specifications contained in Service Instruction section titled ""Center Support Component Dimensions" ".
Center Support Component Dimensions
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| Illustration 12 | g01102995 |
Left-hand center frame (1) Upper bores for the suspension of the frame (2) Lower bores for the suspension of the frame | |
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| Illustration 13 | g01126007 |
Section A-A (1) Upper bores for the suspension of the frame | |
 | |
| Illustration 14 | g01126462 |
Section B-B (2) Lower bores for the suspension of the frame | |
 | |
| Illustration 15 | g01125903 |
Details "C" and "D" (A) 22° (B) 206.0 ± 0.3 mm (8.11 ± 0.01 inch) (C) 122 mm (4.8 inch) (D) 6° (E) 122 mm (4.8 inch) (F) 206.0 ± 0.3 mm (8.11 ± 0.01 inch) | |
 | |
| Illustration 16 | g01105267 |
Sections "E-E", "F-F", "G-G", and "H-H" (G) 210 mm (8.3 inch) diameter, 5° counterbore (H) 167.68 ± 0.05 mm (6.602 ± 0.002 inch) diameter, two holes in line, two places | |
Counterbores (G) are used to center bores (H) .
Procedure to Rework the Axle Housing on the 797 and 797B
Assembly Steps
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| Illustration 17 | g01133323 |
Axle housing (1) Front, upper bores for the suspension (2) Front, lower bores for the suspension (3) Rear bores for the suspension | |
- Perform weld buildup of the bores of the rear support in accordance with this Service Instruction section entitled ""Procedure To Perform Weld Repairs" " and Corporate Product and Process Specification, "IE0099E".
- Perform machining repairs to the rear support bores in accordance with this Service Instruction section titled""Bore Finishing" " to the specifications contained in Service Instruction section titled ""Axle Housing Component Dimensions" ".
Axle Housing Component Dimensions
 | |
| Illustration 18 | g01090279 |
(S/N: 5YW1-237) Top view (A) 1282.8 ± 0.5 mm (50.50 ± 0.02 inch) (B) 237.3 ± 0.3 mm (9.34 ± 0.01 inch) (C) 185.6 ± 0.3 mm (7.31 ± 0.01 inch) (D) Locator "Y1" (E) Locator "Y2" (F) Locator "X1" (G) Locator "X2" (H) Reference750 mm (29.5 inch) (J) 872.5 ± 0.4 mm (34.4 ± 0.02 inch) (K) 723.2 ± 0.4 mm (28.5 ± 0.02 inch) (L) 6° (M) 22° (N) Locator "X3" (P) Locator "Z1" (Q) Reference150 mm (5.9 inch) (R) 731.6 ± 0.4 mm (28.80 ± 0.02 inch) (S) 1266.5 ± 0.4 mm (49.86 ± 0.02 inch) | |
 | |
| Illustration 19 | g01166009 |
(S/N: 5YW238-UP) (S/N: JSM1-UP) Top view (A) 1282.8 ± 0.5 mm (50.50 ± 0.02 inch) (B) 237.3 ± 0.3 mm (9.34 ± 0.01 inch) (C) 196.6 ± 0.5 mm (7.74 ± 0.02 inch) (D) Locator "Y1" (E) Locator "Y2" (F) Locator "X1" (G) Locator "X2" (H) Reference750 mm (29.5 inch) (J) 872.5 ± 0.4 mm (34.4 ± 0.02 inch) (K) 723.2 ± 0.4 mm (28.5 ± 0.02 inch) (L) 6° (M) 22° (N) Locator "X3" (P) Locator "Z1" (Q) Reference150 mm (5.9 inch) (R) 731.6 ± 0.4 mm (28.80 ± 0.02 inch) (S) 1266.5 ± 0.4 mm (49.86 ± 0.02 inch) | |
 | |
| Illustration 20 | g01104054 |
(S/N: 5YW1-237) Section C-C (T) 800.0 ± 0.4 mm (31.50 ± 0.02 inch) (U) 167.68 ± 0.05 mm (6.602 ± 0.002 inch) Diameter, four holes in line (V) 610.0 ± 0.4 mm (24.02 ± 0.02 inch) (W) 242.8 ± 0.4 mm (9.56 ± 0.02 inch) (X) 385.0 ± 0.4 mm (15.16 ± 0.02 inch) (Y) Reference 613 mm (24.1 inch) (Z) Reference 562 mm (22.1 inch) | |
 | |
| Illustration 21 | g01166046 |
(S/N: 5YW238-UP) (S/N: JSM1-UP) Section C-C (T) 800.0 ± 0.4 mm (31.50 ± 0.02 inch) (U) 179.68 ± 0.05 mm (7.074 ± 0.002 inch) Diameter, four holes in line (V) 610.0 ± 0.4 mm (24.02 ± 0.02 inch) (W) 242.8 ± 0.4 mm (9.56 ± 0.02 inch) (X) 385.0 ± 0.4 mm (15.16 ± 0.02 inch) (Y) Reference 613 mm (24.1 inch) (Z) Reference 562 mm (22.1 inch) | |
Note: Each mating pair of bores must be in-line within a diameter 0.8 mm (0.032 inch) zone. The right-hand pair of bores must be in line to the left-hand pair of bores within a diameter 2 mm (0.08 inch) zone.
 | |
| Illustration 22 | g01104048 |
Details "A" and "B" (AA) 205.6 ± 0.3 mm (8.09 ± 0.01 inch) (AB) 102.2 ± 0.3 mm (4.02 ± 0.01 inch) (AC) 167.68 ± 0.05 mm (6.602 ± 0.002 inch) diameter, two holes in line, "H" finish (AD) 167.68 ± 0.05 mm (6.602 ± 0.002 inch) diameter, two holes in line, "H" finish (AE) 205.6 ± 0.3 mm (8.09 ± 0.01 inch) (AF) 102.2 ± 0.3 mm (4.02 ± 0.01 inch) | |
Procedure to Rework the Body on the 797 and 797B
Assembly Steps
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| Illustration 23 | g01133330 |
Truck body (1) Bores for the hoist (2) Bores for the pivot | |
- Perform weld buildup of the bores of the rear support in accordance with this Service Instruction section entitled ""Procedure To Perform Weld Repairs" " and Corporate Product and Process Specification, "IE0099E".
- Perform machining repairs to the rear support bores in accordance with this Service Instruction section titled""Bore Finishing" " to the specifications contained in Service Instruction section titled ""Body Component Dimensions" ".
Body Component Dimensions
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| Illustration 24 | g01090960 |
Bores for the Pivot (6) (A) 237 ± 2 mm (9.3 ± 0.1 inch) (B) 206 ± 2 mm (8.1 ± 0.1 inch) (C) 151.00 ± 0.05 mm (5.950 ± 0.002 inch) diameter, two holes, in-line. "K" finish. | |
Note: The alignment of each pair of holes must permit the entry of a 150.65 mm (5.931 inch) alignment gauge for the diameter. The right-hand pair of bores must be in line to the left-hand pair of bores within 2 mm (0.08 inch) diameter zone.
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| Illustration 25 | g01090957 |
Bores for the Hoist Cylinder (5) (D) 369 ± 2 mm (14.5 ± 0.1 inch) (E) 3083 ± 6 mm (121.4 ± 0.2 inch) (F) 160.20 ± 0.05 mm (6.307 ± 0.002 inch) | |
Note: The alignment of each pair of holes must permit the entry of a 159.87 mm (6.2994 inch) alignment gauge for the diameter. The right-hand pair of bores must be in line to the left-hand pair of bores within 2 mm (0.08 inch) diameter zone.