Usage:
621F (4SK),
623F (5EW),
627F (1DL) Wheel Tractors
Description of Change: New plates have been added to the accumulator support assembly in order to prevent cracking. The first plate was added in order to strengthen the accumulator support plate. The second plate was added in order to reinforce the accumulator clamp mounting area.
Adaptable To: The change to the 8W-9146 Support Assembly that added the 169-4091 Plate is effective with 621F (4SK878), 623F (5EW125) and 627F (1DL640) Wheel Tractors. The change to 8W-9146 Support Assembly that added the 175-4193 Plate is effective with 621F (4SK942), 623F (5EW207) and 627F (1DL712) Wheel Tractors. The changes are adaptable to earlier machines by adding one or both plates using the following procedure.
To fabricate the two plates for supports use the following illustrations, dimensions and weld procedure.
Illustration 1.
Use 10 mm thick of ASTM A570 Grade 45 to fabricate the new 169-4091 Plate.
Illustration 2.
Use 10 mm thick of ASTM A570 Grade 45 to fabricate the new 175-4193 Plate.
Illustration 3.
8W-9146 Support Assembly with typical locations of new plates.
Illustration 4.
View A-A from Illustration 3.
Refer to Service Magazine, October 6, 1997, Page 44, "Proper Welding Procedure On Machines And Engines With Electronic Controls".
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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 instructions 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 general area. Wear correct eye, ear, and body protection. Do not touch live electrical 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 CRF 1910, available from U.S. Dept. of Labor, Washington, D.C. 20408.
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Weld Specifications And Parameters
NOTE: Welding operator personal protection should be provided to assure that total weld fume in the operators breathing zone does not exceed OSHA limits.
All repair welding operators must be qualified for groove and fillet welding, as outlined in the current ANSI/AWS D14.3. The qualification will be for the SMAW (Shielded Metal Arc Welding) process in the vertical welding positions. The welding operator must also have used this welding process during the last six months or be re-certified for this process before welding. Documentation must be maintained of the weld operators qualifications. The alternate process for this repair could be FCAW (Flux Cored Arc Welding).
The area to be welded and the surrounding area must be at a minimum temperature of 16° C (60° F) before and during welding.
NOTE: Since weld distortion is a possibility, minimizing the heat is important.
The SMAW process shall be used with E7018 (ANSI/ AWS A5.5) welding electrode in open environments. The GMAW or the FCAW (Flux Cored Arc Welding) should be used in enclosed environments. The weld deposited by these electrodes will have the following minimum mechanical properties:
- 500 MPa (72 KSI) Tensile Strength
- 420 MPa (60 KSI) Yield Strength
- 22% elongation in 50 mm (2 in)
- 27 J (20 ft lb) Notch Toughness at -29° C (-20° F)
- 420 MPa (60 KSI) Yield Strength
These are low hydrogen electrodes and must be stored in an electrode oven at 120° C (250° F) when not in use. If the electrodes get damp, scrap or recondition them to the manufacturer's specifications.
Where possible, welds should be made in the flat or horizontal position.
The following chart relates to the electrodes diameter and approximate current settings for welding:
Use the direct current electrode positive (DC reverse polarity) polarity setting and remove the slag after every pass. The weld pass size shall not exceed two times the electrode diameter.
Welding parameters will vary due to weld position and manufacturer of the welding electrode.
Clean the metal of oil, grease, paint, and dirt in the area to be welded. Attach the welding ground cable directly to the area to be welded. Protect all machined surfaces from sparks or splatter produced by the welding, chipping, and/or grinding operations.
The welds shall be free from cracks, porosity, undercut, and incomplete fusion. All weld quality shall conform to ANSI/AWS D14.3.