- Caterpillar Products: All
The following weld application sequence is a general guideline. Always refer to the weld instruction sheet for the most current, specific instructions and procedures.
Note: All weld start and stop points and all weld illustrations are general. These generalizations should be considered identical for all top straps with minor variances. These minor variances are dependent upon actual component strap geometry unless otherwise specified on base edge assembly drawings.
Note: Ensure that there is a 25 degree bevel (J) under each adapter strap location as shown in Illustration 4.
Note: Factory and production variations in weld starts and stops (shown by points (D) to (E) in Illustration 2) is permissible. Stagger starts and stops when possible and consult a facility weld engineer for procedural variations within process capabilities.
Note: Weld zones must not exceed the maximum interpass temperature of 260° C (500° F).
Illustration 1 | g03200360 |
Top view of adapter and base edge showing side strap welds (A) through (H) are weld start points or weld stop points (1) Adapter (2) Base Edge (3) Adapter to base edge strap weld (5) Starter plate |
Illustration 2 | g03204914 |
Top view of adapter and base edge showing end strap welds (A) through (H) are weld start points or weld stop points (1) Adapter (2) Base Edge (3) Adapter to base edge strap weld (4) Lower weld |
Illustration 3 | g03204916 |
(1) Adapter (2) Base Edge (3) Adapter to base edge strap weld |
- Preheat adapters and edge to 150° C (300° F) minimum temperature with a maximum interpass temperature of 260° C (500° F). Assemble adapter bevel with hard contact against the base edge bevel with top strap flush to base edge top surface. Tack welding at mid length in root of weld groove on each side of adapter strap.
- Tack weld a 10 mm (0.40 inch) thick mild steel starter plate (5) to the leading edge of the base edge at the junction of the upper and lower weld groves. Refer to Illustration 1. (Two starter plates per adapter).
- Begin first weld bead at front of top strap J-weld grove root shown as point (B) or (G) in Illustration 1. Apply weld passes in sequence to the groove to point (C) of (H) .
- Move to the other side of the adapter and repeat. Fill both J-grooves with alternating weld passes.
- Start weld pass at point (A) or (F). Weld one continuous pass to the beginning of rear adapter arc (point (C) or (H) ) or continue to weld around rear adapter arc ( (D) to (E) ). Stagger all weld starts and weld stops when possible. No weld stops and starts are recommended from (D) to (E) as shown in Illustration 2.
- Move to the other side of the adapter and repeat Step 5. No weld stops and starts are recommended from (D) to (E) as shown in Illustration 2.
- Return to original welded side and weld another pass. The interpass minimum temperature is 150° C (300° F) and the maximum interpass temperature is 260° C (500° F).
- Continue welding alternate sides of the top strap until both welds are complete. Refer to Illustration 3.
- Weld all adapter straps as per Steps 1 through 8.
- Turn edge over (bottom side up) and arc-air gouge through the starter plates until the upper welds are exposed.
Illustration 4 | g03204957 |
Bottom view of adapter and base edge showing lower weld and cross section (1) Adapter (2) Base Edge (3) Adapter to base edge strap weld (4) Lower weld |
- Fill the lower weld groove (4) by starting welds from alternate ends of the groove as shown in Illustration 4. At completion, the lower weld should be flush with the bottom of the base edge, and blended with the ends of the upper welds as shown in Illustration 4.
- Weld all bottom grooves as per Steps 10 through 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.
- Allow all finished welds to slow cool.
- If using adapter covers, check for oversize welds by test fitting the appropriate adapter cover. Ensure that the pin holes in the rear are lined up.