398-6784 Recommended J Series Two Strap Adapter Welding Sequence {0679, 6800, 6801, 6802, 6803, 6805} Caterpillar

Excavator

All

Wheel Loader

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The following weld application sequence is a general guideline. Always refer to the weld instruction sheet for the most current, and specific instructions and procedures.

Note: All weld start and stop points and all weld illustrations are general. These generalizations should be considered identical for both top straps and bottom straps with minor variances. These minor variances are dependent upon component strap geometry unless otherwise specified on base edge assembly drawings.

Note: Weld zones must not exceed the maximum interpass temperature of 260° C (500° F).

Illustration 1	g03200337
(A) through (J) are weld start points or weld stop points (1) Adapter (2) Base edge

Illustration 2	g03202141
Stagger all weld starts and weld stops (1st) through (6th) represent weld passes (1) Adapter (2) Base edge (3) Adapter to base edge weld (K) 12 ± 3 mm (0.5 ± 0.12 inch)

1. Preheat adapters and edge to 150° C (302° F) minimum temperature with a maximum interpass temperature of 260° C (500° F). Assemble adapter bevel with hard contact against the base edge bevel while equalizing the gaps of the adapter straps. The minimum gap requirement for equalization is 3 mm (0.12 inch) and must be equalized within ± 3 mm (± 0.12 inch) to base edge surfaces. Use soft wire spacers to hold position while tack welding at mid length in root of J-Groove on each side of the top strap.

2. Begin first weld bead at the front of top strap weld groove root at point (B) or (G) as shown in Illustration 1. Apply weld passes in sequence to the groove to point (C) or (H).

3. Move to the other side of the adapter and repeat Step 2. Fill both J-grooves with alternating weld passes.

4. Turn edge over (Bottom side up) and repeat the procedures in Steps 2 and 3 for the bottom straps.

5. Continue welding alternate sides of the bottom strap until grooves are filled.

6. Start the first fillet weld pass at point (A) or (F). Start succeeding weld beads slightly behind the preceding layer to produce a rounded weld start as shown in Illustration 2. Continue welds 25 - 50 mm (1.0 - 2.0 inch) past the rear of the adapter shown by point (D) or (I), while tapering the weld to 3 mm (0.12 inch) at the end. Fillet weld bead passes should also be applied alternately on each side of the strap from front to back as described in Step 2. The final weld pass should be on the previously deposited weld near, but not on, the base edge weld toe.

7. Finish the tail welds. Begin the next weld at the rear of the adapter shown by point (E) or (J) in Illustration 1. Make the weld in one continuous pass 25 - 50 mm (1.0 - 2.0 inch) beyond the rear of the adapter shown by point (D) or (I) in Illustration 1, while tapering the weld to 3 mm (0.12 inch) at the end.

   Note: The same number of fillet weld passes should be applied to each side as per Step 6.

8. Move to the other side of the adapter and repeat Step 7.

9. Weld all bottom straps as per Steps 5 through 8.

10. Turn the edge back over (top side up), and complete the fillet welding of the top straps as per Step 6 through 8.

11. If necessary, use grinding to blend all start, stops, and weld toe undercuts. All weld stops (after initial pass) must tie into previously applied weld ends.

12. Allow finished welds to slow cool.