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1. Remove the main oil pump, hydraulic servo motor and other speed regulating parts in the front bearing box.
2. Remove the lubricating oil pipe, high-pressure oil pipe, speed regulating oil pipe and other oil pipes connected to the front bearing box, and seal the oil pipe port with plastic cloth to prevent sundries from entering.
3. Remove the thermal components and wiring affecting the hoisting of the front bearing box.
4. Remove the cat claw pressing block, fixing bolts and locating pins of the cat claw cushion block. Mark (steel prefix) before disassembly.
5. Install temporary support cushion blocks under the front cat claws on both sides of the cylinder (welding shall be configured on site).
6. Set up two dial indicators at the two front claws of the cylinder, and jack up the claws of the front cylinder by 0.25-0.30mm with two 25t jacks.
7. Pull out the claw cushion block to both sides and remove the corner pin of the front bearing box.
8. Lift the front bearing box with the crane, move forward slowly and stably, and lift out the front bearing box after exceeding the cat’s paw of the cylinder.
9. Turn the front bearing box upside down and clean the bottom and longitudinal keyway. Remove rust and burrs, conduct flaw detection to check whether there are cracks. After there are no defects, clean the bottom surface, apply molybdenum disulfide powder, and blow off the excess powder.
10. Clean the contact surface and longitudinal key of the front bearing box bedplate, and remove rust and burrs.
11. Clean the corner pin, cat claw, cat claw cushion block and other parts.
12. Turn the front bearing box over, restore it to the installation position and install it in place. Measure the bedplate clearance, which shall be less than 0.05mm.
13. Install the claw cushion block and locating pin of the front bearing box, and fasten the fixing bolt.
14. Pull down the cylinder to make the cylinder cat claw fall on the cat claw cushion block.
15. Reinstall the regulating parts of the front box, connecting oil pipes, thermal element wiring, etc.
1. The temporary support supporting the cylinder shall be prepared and welded firmly and stably.
2. The jack supporting the cylinder shall be used in a standardized manner. And prevent collision.
3. Before lifting, check whether the lifting equipment and lifting tools are normal.
4. Before withdrawing, check whether there are obstacles preventing the extraction of the front box.
5. When cleaning and grinding the sliding surface of the bedplate, the grinding wheel shall not be used, but the steel wheel or shutter wheel shall be used for cleaning, and excessive grinding shall not be allowed. The surface should be bright without high point burr.
6. After the contact surface of the platen is cleaned, apply molybdenum disulfide dry powder and remove excess powder. It is recommended that the owner apply oil to the platen regularly after the operation of the equipment.