VHS-60/4 and VHS-70/4 Demolition and Scrap Shears Caterpillar

General Guidelines for Buildup and Hard Surfacing

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Personal injury or death can result from fumes, gases and ultraviolet rays from the weld arc. Welding can cause fumes, burn skin and produce ultraviolet rays. Keep your head out of the fumes. Use ventilation, exhaust at the arc, or both, to keep fumes and gases from your breathing area. Wear eye, ear and body protection before working. Protect yourself and others; read and understand this warning. Fumes and gases can be dangerous to your health. Ultraviolet rays from the weld arc can injure eyes and burn skin. Electric shock can cause death. Read and understand the manufacturer's instructions and your employer's safety practices. Do not touch live electrical parts.

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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.

The steel that is used in Verachtert shears is strong and durable. However, this steel requires special attention during maintenance. Pay very close attention to the preheat and postheat instructions and follow the instructions exactly. Review the following guidelines for buildup and hardsurfacing the shear. Detailed instructions on maintaining specific areas of the shear are on the following pages. Contact your Verachtert dealer for further information.

Preheat

Before any thermal process is applied to the steel of the shear, including welding, tack welding, cutting with a torch, and air-arcing, preheat the area according to the following table.

(1) Jaws should be welded at ambient temperatures at or above 15° C (60° F).

(2) Do not allow the temperature of the jaw material to get above 200° C (390° F).

(3) Do not weld on the jaw material if temperature is below 150° C (302° F).

Always keep the burner head at a minimum of 250 mm (10 inch) away from the jaws in order to maintain the materials qualities. Preheat an area of at least 200 mm (8 inch) around the point that will be welded. After heating the area, wait for 3 minutes before measuring the temperature. Do not measure the temperature directly after removing the heat source. Measure preheat temperature at a distance of 75 mm (3 inch) away from the point that will be welded at the opposite side of the heated side. If using an infrared temperature meter, keep the meter 300 mm (12 inch) to 500 mm (19.5 inch) away from the jaws, in order to prevent inaccurate measurements. If using temperature-indicating sticks, use the correct stick for the range of temperatures 125° C (255° F) to 175° C (345° F).

Preheat must be uniform throughout the thickness of the material and maintained until all welding has been completed. Avoid cyclic heating and large temperature swings.

Localized gas torches or thermal strip blankets may be used for preheating.

Interpass

The temperature of the weld area must be between 125° C (255° F) to 175° C (345° F) before another weld pass may be made. If the temperature has dropped below the minimum temperature, the weld area should be heated again to the minimum temperature. If the temperature is above the maximum interpass temperature, the weld area must be allowed to cool slowly until the weld area is below the maximum temperature. Do not allow material to be heated above 200° C (390° F). Do not accelerate the cooling process. Accelerating the cooling process will result in increased brittleness of the material.

Wrap heat blankets around the welded jaws immediately after welding has ended. Do not remove the welding blankets until the temperature has dropped below 80° C (175° F). Dropped below this temperature will typically take approximately 4 hours or more.

Plan to perform buildup and hard surfacing at the end of the day or when there will be adequate time for the welded areas to cool before putting the shear back into service.

Buildup Material

When building up the shear jaws, closely adhere to the above heating procedures. The proper buildup material for the jaws should conform to the following:

• AWS A5.28-100: ER100S-G

Hard surface Material

The steel that is used in Verachtert shears is strong and durable. Hard surfacing of a new unused jaw is not necessary. Hard surfacing should not be attempted. However, if the jaws have worn, the jaws should first be built up. If hard surfacing the jaws, the weld material should match the following chemical properties:

Some products that meet these properties are:

• LINCOLN Wearshield 420

• ESAB Wear-Arc 5I

• ESAB OK Tubrodur 15.50

Handling and storage of weld materials

Follow the weld manufacturers instructions for handling and storage closely. Make sure that the electrodes or wire are free of moisture. Moisture can cause hydrogen-cracks and porosity in the weld and possibly the base metal beneath the weld.

Weld Quality

Quality and attention to the detail in welding can significantly affect the life of the shear. Verachtert strongly recommends that only qualified and certified welders perform this work. Ensure that the weld consumables and base materials are clean, dry, and free of grease, paint, dirt, or any foreign substance that may harm the weld.

Build up the Moveable Jaw

1. Clean the shear.

2. Place the shear in a horizontal position. Rotate the shear 180 °. Open the jaws of the shear.

3. Lock the jaws in an open position. The following procedures describe maintaining the jaws in the open position.
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   Table 3

   Sales Model	Shear Locks
   VHS-60/4	325-6438
   VHS-70/4	327-5368

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   Illustration 1	g02174182
   Lock for the hydraulic cylinder on the VHS-60/4 and VHS-70/4 shears

   1. In order to hold the shear in the open position for the VHS-60/4 and VHS-70/4, insert shear lock (1) through the hole on the side of the shear. Slide the pipe on the shear lock (1) all the way through the shear. Insert bolt (2) into the hole in the end of the pipe. Install nut (3) onto the bolt. Refer to Table 3 for the part numbers of the shear locks.

Note: Wear of the external surfaces of the moveable jaw is normal. Wear exceeding the values specified in the section below requires rebuild of the jaw surfaces.

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Illustration 2	g02181274

4. Remove all components of the cutting edge group and the piercing tip.

5. Clean debris from the surface to be welded. Grind the surface.

6. Preheat the specific area of repair. Refer to Operation and Maintenance Manual, "General Guidelines for Build-up and Hard Surfacing" for information on preheat.

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Illustration 3	g02170377
Build up direction

7. Build up original shape. For the specific welding material, refer to Operation and Maintenance Manual, "General Guidelines for Build-up and Hard Surfacing".

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NOTICE
Do not apply weld to the cutting blades or the piercing blades. Do not attach a ground cable to the cutting blades or the piercing blades. Welding or passing current through the cutting blades or the piercing blades may result in damage to the blades.

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Illustration 4	g02181474
Maximum allowable dimensions from front of new piercing blades surface

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Illustration 5	g02181475
Maximum allowable dimension of jaw parent material below new piercing blade surface

Note: Ensure that the following instructions are performed with new piercing blades installed.

8. Inspect the moveable jaw for wear as shown in illustrations 4 and 5. Wear beyond the maximum limits indicated requires rebuild of the jaw surfaces.

9. Apply weld along the front length of the moveable jaw as shown in illustration 5. Utilize the piercing blades as a template. Ensure that all weld operations are parallel with the drop-side and cut-side of the moveable jaw. Refer to Operation and Maintenance Manual, "General Guidelines for Build-up and Hard Surfacing".

10. Final welded surface should be flush with or approximately 2 mm (0.079 inch) below the piercing blade surfaces.

11. Cool the weld slowly to room temperature. Remove all the debris from the weld.

12. Paint the welded area with primer. Allow the primer to dry. Paint the welded area with a final coat of paint.

13. Install all components of the cutting edge group and the piercing tip. Remove the shear lock.

Build up the Fixed Jaw

1. Clean the shear.

2. Place the shear on a horizontal position. Rotate the shear 180 °. Open the jaws.

3. Lock the jaws in an open position. Refer to Operation and Maintenance Manual, "Build up the Upper Jaw" for more information.

4. Remove all components of the cutting edge group. Remove paint from the surface of the jaw that requires build up. Grind the needed surfaces.

5. Use the welding material to repair the area. For the specific welding material, refer to Operation and Maintenance Manual, "General Guidelines for Build-up and Hard Surfacing".

6. Preheat the specific service area of repair. Refer to Operation and Maintenance Manual, "General Guidelines for Build-up and Hard Surfacing" for information on preheat.

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Illustration 6	g02174072
Build up direction

7. In order to build up the original shape, weld in the direction of the grain.

8. Cool the weld slowly to room temperature. Remove all the debris from the weld. Paint the welded area with primer. Allow the primer to dry. Paint the welded area with a final coat of paint.

9. Install all components of the cutting edge group. Remove the shear lock.

Pocket Repair for the Bolt on Piercing Tip

Repetitive high force loads will deform the leading surface of piercing blade pocket. When deformation occurs, this surface will need to be restored to the original shape to prevent piercing blade failure.

1. Ensure that this procedure is performed with new piercing blades installed.

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Illustration 7	g02181414

2. Check the clearance at the front mating surfaces of the piercing blades (9A) and (9B) and the moveable jaw. The clearance should be no more than 0.2 mm (0.008 inch).

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NOTICE
Do not perform this procedure if the clearance is equal to or less than 0.2 mm (0.008 inch).

3. Remove the piercing blades (9A) and (9B) from the moveable jaw.

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Illustration 8	g02181417

4. Position the shear so that the leading surface of the piercing tip (A) is horizontal and facing upward as shown in illustration 8.

5. Preheat the jaw. Refer to Operation and Maintenance Manual, "General Guidelines for Build-up and Hard Surfacing" for information on preheat.

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Illustration 9	g02181422

6. Weld area (A) utilizing ER100 specification welding wire. The final weld surface should be above the original surface as shown in illustration 9.

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Illustration 10	g02181423

7. Grind the weld surface smooth as shown in illustration 10.

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Illustration 11	g02181425

8. Install rebuild templates (B) as shown in illustration 11. There is one template for each side. Ensure that the templates are clamped in place. Refer to table 4 for the appropriate template.
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   Table 4

   Sales Model	Rebuild Templates
   VHS-60/4	328-3481
   VHS-70/4	331-6255

9. Place a straight edge over the templates (B) as shown in illustration 11. Check the welded surface for high and low areas. The maximum height of the surface must not extend above the templates. The minimum depth must be no lower than 0.1 mm (0.004 inch) below the templates.

10. Install the cut-side piercing blade (9B). Refer to Operation and Maintenance Manual, "Piercing Blade - Installation". Ensure that the piercing blade does not bind on the welded surface.

    Note: If the piercing blade binds on the welded surface, reduction of the welded surface height may be required. Repeat steps 6 through 10 as required.

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Illustration 12	g02182555

11. Measure the clearance between the piercing blade (9B) and the repaired surface (A). The maximum allowable clearance is 0.2 mm (0.008 inch) at any point along the repaired surface (A) .

12. Remove the cut-side piercing blade (9B) .

13. Repeat steps 10 and 11 for the drop-side piercing blade (9A) .

14. Install the piercing blades (9A) and (9B). Refer to Operation and Maintenance Manual, "Piercing Blade - Installation".

Hard Surfacing of the Shear Jaws

1. Clean the shear.

2. Place the shear on a horizontal position. Open the jaws.

3. Lock the jaws in an open position. Refer to Operation and Maintenance Manual, "Build up the Upper Jaw" for more information.

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Illustration 13	g02181736
(X) Hard surface weld on top of moveable jaw

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Illustration 14	g02181737
(X) Hard surface weld on inside of moveable jaw

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Illustration 15	g02181738
(X) Hard surface weld on inside of fixed jaw

4. Apply single pass welds (X) with a height of approximately 3 mm (0.118 inch).

5. Ensure that all welds (X) are aligned with the direction of jaw motion. Refer to illustrations 13 through 15.

6. Remove all the debris from the weld. Paint the welded area with primer. Allow the primer to dry. Paint the welded area with a final coat of paint.

• Do not apply weld (X) within 15 mm (0.59 inch) of the radius of the apex of the moveable jaw.

• Do not apply weld (X) within 15 mm (0.59 inch) of the throat of the moveable jaw and fixed jaw.

• Weld only the areas as shown in illustrations 13 through 15.

• Weld start and stop points must be staggered approximately 15 mm (0.59 inch) as shown in illustrations 13 through 15.

• Do not apply welds (X) within 15 mm (0.59 inch) of the edge of the parent material.