CONFIDENTIAL TIBU4522-00

SOLUTION:

There may be instances where the J-Series base edge assembly has worn adapters that need replacement, but the condition of the base edge is acceptable. Also, a customer may have an inventory of the thinner edges and desires an upgrade to the K-Series adapters. It is not recommended, but the customer may desire to use an existing thinner base edge while upgrading to the new, larger size K-series adapters. Refer to Table 1 for comparison of the thickness for the base edge adapters.

Table 1.
¹ K170 adapters require a 35° base edge bevel. Adapter conversion is not practical.

Table 2.

USING LOADER K-SERIES CENTER ADAPTERS ON J-SERIES BASE EDGES

Illustration 1. J460 Tip And Adapter With A K110 Tip And Adapter
(A) 232-2114 Tip Adapter (K110)
(B) 220-9113 Penetration Plus Tip (K110)
(C) 47.6 mm (1.87 inch)
(D) 54.8 mm (2.16 inch)
(E) 159-0459 Penetration Tip (J460)
(F) 159-0464 Tip Adapter (J460)

The angle of the adapter nose on K-Series loader adapters (15° ) is steeper than J-Series adapters (8° ). However, the resultant position of the tip remains very close. Illustration 1 shows a J460 tip superimposed over a K110 tip for their respective adapters. Reworking a J600 adapter to a K150 adapter is comparable. Reworking a J550 adapter to a K130 adapter will extend the tip forward approximately 25 mm (1.0 inch). Welding instructions are located in the weld instruction section of this publication.

The time and cost of using loader adapters on J-Series base edges may be acceptable. Fatigue life of the base edge is another aspect that should be considered. Increasing the thickness of the base edge improves the fatigue life of the edge assembly. Using a base edge that is 60 mm (2.4 inch) thick instead of a base edge that is 50 mm (2.0 inch) thick can improve the fatigue life by approximately 3.5 times. The change to a base edge that is 70 mm (2.8 inch) thick instead of a base edge that is 60 mm (2.4 inch) thick can improve the fatigue life by approximately 3 times. Using a base edge that is 80 mm (3.2 inch) thick instead of a base edge that is 70 mm (2.8 inch) thick can improve the fatigue life by approximately 2.5 times. Improved fatigue life should be considered for machines with buckets that are working in severe applications.

USING EXCAVATOR K-SERIES CENTER ADAPTERS ON J-SERIES BASE EDGES

Make spacer plates from 10 mm (0.4 inch) thick T-1 or comparable steel plate, if the existing base edge is reused. If metric plate is not available, 3/8 inch (9.52 mm) plate is acceptable.

Illustration 2. Cardboard Template

Make a template for the spacer plate by placing a piece of cardboard under the top adapter strap up to the bevel angle. Mark the outline of the J-groove for the strap. Refer to Illustration 2.

Illustration 3. Template
(G) 24 mm (0.94 inch)

The adapter will be positioned higher on the base edge bevel. A gap will exist at the bevel transition and would be difficult to weld. Add 24 mm (0.94 inch) to the wide end of the template. Refer to Illustration 3. The addition of 24 mm (0.94 inch) is applicable to all three K-Series conversions.

Illustration 4. Side View Of A Typical Spacer Plate
(G) 24 mm (0.94 inch)
(H) Spacer
(J) 22.5°
(L) 10 mm (0.4 inch)

Use the template and fabricate the number of plates that are needed. Grind a 22.5° chamfer on the 24 mm (0.94 inch) extension of the spacer plate. Refer to Illustration 4.

Gouge out the welds of the former adapters. Remove the former adapters. Grind the top and bottom surfaces of the base edge flat. The spacer plates may not slide completely into position if the base edge is ground improperly. Excessively deep gouges, which will not be welded over with the new adapters, should be filled with weld and ground flush.

Illustration 5. Adapter And Base Edge
(H) Spacer
(K) 2 mm (0.08 inch) diameter wire

Slide the adapters onto the base edge at the proper location. Make sure that the adapters are against the bevel. Place the spacer plates under the top straps and separate the adapter straps and the spacer plates with two 2 mm (0.08 inch) diameter soft iron wire spacers between them. Refer to Illustration 5.

WELDING PROCEDURE

Additional J-groove and fillet weld passes will be required on the top straps of the adapters when using the 10 mm (0.4 inch) spacer plates.

1. Preheat the adapters and the base edge to 149° -260° C (300° -500° F). Preheating is required for tack welding the adapters in position.
2. Use a flux cored wire such as AWS E71T-1 (all position) with hydrogen control and gas shielding. The use of AWS E70T-5 welding wire is acceptable, if the welds are made in a flat and horizontal position. AWS E7018 stick electrodes may also be used, but make sure that extra care is taken with the weld stop/starts.



Illustration 6. Top View Of The Adapter And The Base Edge

3. Begin the first weld pass at the front of the top strap weld groove. Weld a continuous pass to the back of the adapter at its midpoint. Refer to Illustration 6.



Illustration 7. Top View Of The Adapter And The Base Edge

4. Move to the opposite side of the adapter top strap. Start the second weld pass at the front of the weld groove. Weld a continuous pass to the back of the adapter at its midpoint. Refer to Illustration 7.
5. Return to the original welded side and weld another pass. Interpass temperatures should be a minimum of 120° C (250° F).
6. Continue welding alternate weld passes on the top strap until the J-groove is filled.
7. Weld each of the adapter top straps.
8. Turn the base edge over and repeat Steps 1-6 for the bottom straps.



Illustration 8. Welds For The Adapter And Base Edge

9. After the J-grooves have been filled, continue with alternating fillet welds until completed. Make the welds continuous to the back of the adapters, if possible. Do not have any weld stop/starts on the bevel of the base edge, if stick electrodes are used. Fillet welds should not have any abrupt starts at the front of the adapters. Start the first fillet weld pass at Point A. Refer to Illustration 8. Stagger the next welds slightly shorter than the preceding welds in order to give a tapering affect. Make the final pass (B) on top of the weld pass that is fused to the base edge.
10. Weld all bottom straps.
11. Turn the base edge over. Complete the fillet welding of each top strap. Continue with multiple alternate passes until completed.
12. Blend all weld toe undercuts and weld stop/starts.

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