PLATE-CENTER 9G0324 - Caterpillar

Illustration 18 g02187137
Before full length welds are applied at the rear of the base edge, verify that the base edge is level with the bucket as shown in Illustration 2 and Illustration 14. The sidebars and corner adapters should then be attached with stringer welds to keep the base edge in position. Preheat the bottom of the sidebars to 149°-232° C (300°-450° F) before welding. The butter beaded surfaces of the adapters and rear of the base edge behind the adapters do not require preheating before welding, but heating those areas to 93° C (200° F) will insure that no moisture is present. Apply stringer welds between the bottom of the sidebars and corner adapters as shown in Illustration 18.
Illustration 19 g02187314
Apply a full length stringer weld between the bowl and base edge to fill the gap as shown in Illustration 19.
Illustration 20 g02144372
Refer to Illustration 20. If hand welding, start at the center of the base edge and weld to the sides of the bucket, Apply at least three weld passes (P). Always stagger each weld start at a slightly different location. Interpass temperatures should not exceed 260° C (500° F). If using a track welder, start close to one side of the bucket and weld across to the other side. Fill in the ends by hand where the track burner could not reach. Stagger each weld pass start and stop. As always, remove the slag created during each weld pass.
Illustration 21 g02144373
Rotate the bucket in order to expose the underside of the bucket. Back gouge the underside of the top weld (P) at point (R) in order to provide unobstructed access to the top weld. Refer to Illustration 20 and Illustration 21.
Apply weld passes until the bottom groove (S) is completely filled. Stagger the starting points of the welds and remove the slag after each weld pass.
Illustration 22 g02144374
Refer to Illustration 22. Rotate bucket upright and complete filling in the top base edge bevel groove (P) with weld.Note: During multiple weld passes, the heat generated in the base edge may cause it to become uneven with the bowl. Periodically check the base edge and if warping starts, stop welding, rotate the bucket over and apply weld to the other side.
There is a possibility that the last welds being applied may run over onto the top or bottom of the base edge beyond the butter beading. If this occurs, the base edge must be preheated to a temperature of 149°-232° C (300°-450° F) before welding, regardless of the welding process being utilized. The welding should utilize the back tempering technique where the last pass of the weld does not touch the adjacent material and acts to stress relieve the previous weld pass.
Disc grind the last pass weld, blending the weld smoothly into the base edge surface.
Illustration 23 g02144375
(T) Height of bevel groove weld (U) Height of fillet weld (U=T+2 mm (0.08 inch) (V) Base leg of fillet weld (V=1.25*U)
Illustration 24 g02144378
Illustration 25 g02144376
View A-A
Illustration 26 g02144370
Preheat the bottom of the sidebars to 149°-232° C (300°-450° F).