2012/02/28 Caterpillar

Excavator:

312D (S/N: RKF1-UP)

315D (S/N: TLE1-UP)

319D (S/N: WBJ1-UP; ZGZ1-UP)

Modification may be required for boom, stick, and frames on certain 312D, 315D, and 319D Excavators. Refer to the following procedures to rework the stick, boom, and frames.

Welding Requirements

Welding quality is critical to the success of the installation procedures. Welds must be smooth and continuous. Do not undercut the welds. No overlap is allowed. Grind the ends of the welds to a smooth radius.

Prepare the metal for welding according to the next section. Refer to the illustrations in this special instruction for welding symbols and specifications.

Be sure that all electrodes are dried. The electrodes can be dried by heating the electrodes to 300°C (572°F). The electrodes must be dried for at least 30 minutes.

Do not weld in windy conditions. Do not weld when temperatures are below 16°C (60°F).

Penetration characteristics may vary greatly depending on the following conditions:

• Electrode diameter

• Shielding gas

• Welding current

• Plate thickness

The following items also affect the welds:

• Geometry of welded joints

• Surface conditions

• Composition of the base metal and of the electrode

For more welding information, consult the General Welding Procedures, REHS1841.

Preparing the Metal for Welding

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Personal injury can result from flame cutting or welding on painted areas. The effect of gasses from burned paint is a hazard to the person doing the cutting or welding. Do not flame cut or weld on painted areas.

All grease, paint, and foreign objects must be removed before welding. Any of these materials will discharge gas which will cause porosity in the weld deposit. Water and rust will cause hydrogen embrittlement. Hydrogen embrittlement causes cracks in the weld deposit.

Remove foreign objects with a wire brush, a buffer, or a grinder. Shot blasting the appropriate areas will also remove foreign material.

Note: After welding, allow all areas to cool to room temperature. After the areas have cooled, paint the area with primer. After the primer has dried, coat the area with Cat 4C-4200 Yellow Paint .

Stick Rework Procedure

Illustration 1	g02897842
Bucket Cylinder Head Pin Location (1) 7Y-2319 Boss (2) New Stick (3) Old Stick

Refer to Illustration 1 for the differences in Stick Groups. Boss 7Y-2319 (1) is on the opposite side of the stick. No rework is necessary.

Boom Rework Procedure For 264-1588 Boom and Bearing As

Overview of Rework to Boom

Illustration 2	g02884079
New Boom Vs Old Boom Overview (1) 269-1485 Plate (2) 117-5604 Stud (3) 7Y-4171 Plate (5) Boom from new supplier (6) Boom from old supplier (A) Back boom plate - Section A (B) Middle boom plate - Section B (C) Front boom plate - Section C

For an overview of the Boom Rework Procedure to make boom (5) function as boom (1). Refer to Illustration 2. This work will allow the hydraulic lines to be installed on the boom.

Boom Foot - Section A

Illustration 3	g02884096
Close up of Section A (1) 269-1485 Plate (5) Boom (A) 132 mm (5.20 inch) (B) 160 mm (6.30 inch)

1. Prepare area for welding of plate (1) to boom (5). Remove paint as necessary.

2. Mark location for plate (1) to boom (5). Measure to the center of the bolt hole. Using the measurements given in Illustration 3.

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Illustration 4	g02885096
Close up of Section A (Lower Right Corner) (1) 269-1485 Plate (5) Boom (C) 5 mm (0.20 inch) fillet weld. (W1) SMAW AWS A5.1 E7018 or Equivalent

Note: Do not weld 10 mm (0.39 inch) from both ends of plate (1).

3. Weld Plate (1) to boom (5) with 5 mm (0.20 inch) fillet weld (C). Refer to Illustration 4.

4. Let welded area cool.

5. Prepare welded area for paint.

6. Apply a primer coat to prepared area. Refer to Step 1.

7. After primer coat has dried, apply a finish coat to prepared area. Use CAT 4C-4200 Paint (4) .

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Illustration 5	g02885377
Close Up of Section A (Upper Front) (2) 117-5604 Stud (5) Boom (D) 127 mm (5.0 inch) (E) 232 mm (9.13 inch) (F) 114 mm (4.49 inch) (G) 100 mm (3.93700 inch)

8. Prepare area for welding of studs (2). Remove paint as necessary.

9. Mark location for stud (2) on boom (5) using measurements (E) and (F). Refer to Illustration 5.

10. Mark location for stud (2) on boom (5) using measurements (D) and (G). Refer to Illustration 5.

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Illustration 6	g02890111
Stud Weld Area (2) Stud (H) 3 mm (0.12 inch) Fillet (W1) SMAW AWS A5.1 E7018 or Equivalent

11. Weld studs (2) to boom (5). Weld all around studs (2) with a 3 mm (0.12 inch) fillet weld (H). Refer to Illustration 6.

12. Let welded area cool.

13. Prepare welded area for painting.

Note: Cover threaded hole to ensure that no primer gets inside of studs (2) .

14. Apply a primer coat to prepared area. Refer to Step 8.

Note: Cover threaded hole to ensure that no paint gets inside of studs (2) .

15. After primer has dried, coat the prepared area. Use Cat 4C-4200 Paint (4) .

Middle Boom Plate - Section B

Illustration 7	g02887802
Close Up of Section B (Lower) (2) 117-5604 Stud (3) 7Y-4171 Plate (5) Boom (J) 1540 mm (60.63 inch) (K) 81 mm (3.19 inch) (L) 200 mm (7.87 inch) (M) 1698 mm (66.85 inch) (N) 81 mm (3.19 inch) (P) 127 mm (5.00 inch) (R) 70 mm (2.76 inch)

1. Prepare areas for welding of studs (2) and plates (3) to boom (5). Remove paint as necessary.

Note: Refer to Illustration 7 for Steps 2 through 5 for location of studs and plates.

2. Mark location for stud (2) to boom (5), using measurements (J) and (K) .

3. Mark Location for stud (2) to boom (5) using measurements (P) and (N) .

4. Mark location for plate (3) to boom (5) using measurements (M) and (R). Measure to the center of the bolt hole.

5. Mark location for plate (3) to boom (5) using measurements (M) and (L). Measure to the center of the bolt hole.

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Illustration 8	g02891477
Close Up of Section B Weld area (Lower) (2) 117-5604 Stud (3) 7Y-4171 Plate (5) Boom (S) 3 mm (0.12 inch) fillet weld (T) 5 mm (0.20 inch) fillet weld (W1) SMAW AWS A5.1 E7018 or Equivalent

Note: Refer to Illustration 8 for Steps 6 through 7.

Note: Do not weld 10 mm (0.39 inch) from both ends of plates (3) .

6. Weld studs (2) on boom (5) with a 3 mm (0.12 inch) fillet weld (S) .

7. Weld plates (3) on boom (5) with a 5 mm (0.20 inch) fillet weld (T) .

8. Let welded areas cool.

9. Prepare welded areas for paint.

Note: Cover threaded hole to ensure that no primer gets inside studs (2) .

10. Apply a primer coat to prepared areas. Refer to Step 1.

Note: Cover threaded hole to ensure that no paint gets inside studs (2) .

11. After primer has dried, apply a finish coat to prepared areas. Use Cat 4C-4200 Paint (4) .

Front Boom Plate - Section C

Illustration 9	g02888842
Close Up of Section C (3) 7Y-4171 Plate (5) Boom (AB) 697 mm (27.44 inch) (AC) 697 mm (27.44 inch) (AD) 501 mm (19.7 inch) (AE) 501 mm (19.7 inch) (AF) 45 mm (1.77 inch) (AG) 45 mm (1.77 inch) (AH) 45 mm (1.77 inch) (AJ) 45 mm (1.77 inch)

1. Prepare area for welding plates (3) to boom (5). Remove paint as necessary.

Note: Refer to Illustration 9 for Steps 2 through 5.

2. Mark location for plate (3) to boom (5) using measurements (AB) and (AF). Measure to the center of the bolt hole.

3. Mark location for plate (3) to boom (5) using measurements (AC) and (AH). Measure to the center of the bolt hole.

4. Mark location for plate (3) to boom (5) using measurements (AD) and (AG). Measure to the center of the bolt holes.

5. Mark location for plate (3) to boom (5) using measurements (AE) and (AJ). Measure to the center of the bolt hole.

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Illustration 10	g02891959
Close Up of Section C (Weld area) (3) 7Y-4171 Plate (AK) 5 mm (0.20 inch) fillet weld (W1) SMAW AWS A5.1 E7018 or Equivalent

Note: Refer to Illustration 10 for Steps 6 through 9.

Note: Do not weld 10 mm (0.40 inch) from both ends of plate (3) .

6. Weld plate (3) to boom (5) on weld area (AN) using a 5 mm (0.20 inch) fillet weld (AK) .

7. Weld plate (3) to boom (5) using a 5 mm (0.20 inch) fillet weld (AK) .

8. Weld plate (3) to boom (5) using a 5 mm (0.20 inch) fillet weld (AK) .

9. Weld plate (3) to boom (5) using a 5 mm (0.20 inch) fillet weld (AK),

10. Prepare welded areas for paint.

11. Apply a primer coat to prepared areas. Refer to Step 1.

12. After primer has dried, coat prepared areas. Use Cat 4C-4200 Paint (4) .

Upper Frame Rework Procedure

The following procedure will be used to rework the new parts to match the old parts. The rework is the same for 315D and 319D. The rework for 312D has one difference from the 315D and 319D. This difference is in Step 14.

Illustration 11	g02878636
Upper Frame Assembly (3) 7y-8741 Plate (4) Upper Frame Assembly

1. Remove plate (3) from the upper frame assembly (4) .

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Illustration 12	g02878456
Close Up of Upper Frame Assembly (Swivel Cutout) (1) 287-8569 Plate (4) Upper frame assembly (5) Swivel cutout (A) 44 mm (1.73 inch)

2. Prepare area for welding plate (1) to upper frame assembly (4). Remove paint as necessary.

3. Mark location for plate (1) using measurement (A). Refer to Illustration 12.

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Illustration 13	g02882683
Close Up of Upper Frame Assembly (Weld Area) (5) Swivel cutout (B) 1.5 mm (0.06 inch) Penetration (C) 6 mm (0.24 inch) Fillet Weld (W1) SMAW AWS A5.1 E7018 or Equivalent

4. Weld plate (1) to upper frame assembly (4) with a 6 mm (0.24 inch) fillet weld (C) that has 1.5 mm (0.06 inch) penetration (B) .

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Illustration 14	g02882876
Close Up of Upper Frame Assembly (Front) (2) 137-8431 Plate (4) Upper frame assembly

5. Prepare area for welding of plate (2). Remove paint as necessary.

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Illustration 15	g02883223
(2) 137-8431 Plate (4) Upper frame assembly (D) 261 mm (10.28 inch) (E) 325.4 mm (12.81 inch)

6. Mark location for plate (2) on upper frame assembly (4) using measurements (D) and (E). Refer to Illustration 15.

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Illustration 16	g02883401
Weld area (137-8431 Plate ) (2) 137-8431 Plate (F) 5 mm (0.20 inch) fillet weld (W1) SMAW AWS A5.1 E7018 or equivalent

7. Weld plate (2) to the upper frame assembly (4) using a 5 mm (0.20 inch) fillet weld (F) .

8. Let welded areas cool.

9. Prepare welded areas for paint.

10. Apply a rust prevention coat to prepared area. Refer to step 2.

11. After the rust prevention coat dries, apply a finish coat to prepared area. Refer to step 2.

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Illustration 17	g02881040
Upper Frame Assembly (Back) (6) Bolt hole (7) Bolt hole

12. Locate bolt hole (6) and bolt hole (7). Refer to Illustration 17. These bolts holes will need to be slotted.

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Illustration 18	g02881178
Dimensions for slots 315D/319D Vs. 312D (G) 40 mm (1.6 inch) (H) 18 (0.71 inch) (J) 26 mm (1.02 inch) (K) 18 mm (0.71 inch)

13. This step only applies to 319D and 315D. Remove material around bolt hole (1) and bolt hole (2) using measurements (G) and (H). Refer to Illustration 18.

14. This step only applies to 312D. Remove material around bolt hole (1) and bolt hole (2) using measurements (J) and (K). Refer to Illustration 18.

15. Remove any burrs and smooth the edges of the slots.

16. Apply a rust prevention coat on area that was slotted. Refer to Step 13 for 315D/319D or Step 14 for 312D.

17. After rust prevention coat dries, apply a finish coat on area that was slotted. Refer to Step 13 for 315D/319D or Step 14 for 312D.

Undercarriage Rework Procedure

The part numbers have changed for 319DL and 319DL N. No modification is necessary to install the parts onto the machine.

Modification is necessary for rework for 312D and 312D L. The following procedure will show the necessary rework.

Rework for 312D

Illustration 19	g02879997
Rework for 312D (269-1645 Undercarriage Frame As ) (A) 111 mm (4.37 inch) (B) 105 mm (4.13 inch) (C) 18 mm (0.71 inch) (1) 269-1645 Undercarriage Frame As (2) Bolt hole (3) Bolt hole (4) Bolt hole (5) Bolt hole (6) Bolt hole (7) Bolt hole (8) Bolt hole (9) Bolt hole

Note: Refer to Illustration 19 for Steps 1 - 8

1. Mark from the center of the bolt hole (2) with measurements (A) and (C).

2. Mark from the center of the bolt hole (3) with measurements (A) and (C).

3. Mark from the center of the bolt hole (4) with measurements (B) and (C) .

4. Mark from the center of the bolt hole (5) with measurements (B) and (C).

5. Mark from the center of the bolt hole (6) with measurements (B) and (C) .

6. Mark from the center of the bolt hole (7) with measurements (B) and (C) .

7. Mark from the center of the bolt hole (8) with measurements (A) and (C) .

8. Mark from the center of the bolt hole (9) with measurements (A) and (C) .

9. Drill and tap the locations that were marked in Step 1 through Step 8 to bolt size M16 x 2.

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Rework for 312D L

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Illustration 20	g02880076
Rework for 312D L (269-1649 Undercarriage Frame As ) (A) 111 mm (4.37 inch) (C) 18 mm (0.71 inch) (D) 112 mm (4.41 inch) (10) Bolt hole (11) Bolt hole (12) Bolt hole (13) Bolt hole (14) Bolt hole (15) Bolt hole (16) Bolt hole (17) Bolt hole (18) Bolt hole (19) Bolt hole (20) Bolt hole (21) Bolt hole (22) 269-1649 Undercarriage Frame As

Note: Refer to Illustration 20 for Steps 1 - 12

1. Mark from the center of the bolt hole (10) with measurements (A) and (C) .

2. Mark from the center of the bolt hole (11) with measurements (A) and (C).

3. Mark from the center of the bolt hole (12) with measurements (D) and (C) .

4. Mark from the center of the bolt hole (13) with measurements (A) and (C).

5. Mark from the center of the bolt hole (14) with measurements (A) and (C).

6. Mark from the center of the bolt hole (15) with measurements (D) and (C) .

7. Mark from the center of the bolt hole (16) with measurements (D) and (C) .

8. Mark from the center of the bolt hole (17) with measurements (A) and (C) .

9. Mark from the center of the bolt hole (18) with measurements (A) and (C) .

10. Mark from the center of the bolt hole (19) with measurements (A) and (C) .

11. Mark from the center of the bolt hole (20) with measurements (A) and (C) .

12. Mark from the center of the bolt hole (21) with measurements (D) and (C) .

13. Drill and tap the locations that were marked in Step 1 through Step 12 to bolt size M16 x 2.