1. Project Overview

This operation is to replace the output shaft/input shaft oil seal of the main reducer of the overhead passenger device. The oil seal is aging, leaking, and leaking oil, causing the loss of lubricating oil in the reducer. There are potential risks of equipment wear, overheating, transmission failure, and sick equipment operation. In order to eliminate hidden dangers and ensure the safe and stable operation of the monkey car, this safety technical measure has been compiled to guide on-site maintenance operations.

Operating location: overhead crew unit nose machine room

Job content: shutdown, power off and tag out, drain oil, remove end cover, remove old oil seal, clean sealing surface, replace new oil seal, reset and install, refuel, and test run.

Number of workers: 3 (person in charge 1, maintenance worker 2)

2. Identification of operational risks

1. Failure to completely cut off the power supply or turn on the machine by mistake may cause mechanical strangulation or curling injuries.

2. Working at high altitudes and in gaps between equipment may cause collisions and crushing injuries.

3. When the end cover is removed and the bolts are unevenly stressed, the parts may fall and injure people.

4. Debris and iron filings enter the reducer, causing gears and bearings to wear and lock.

5. The oil seal is incorrectly installed, skewed, and not pressed in place, causing oil leakage again and equipment damage due to lack of oil.

6. There was no inspection before trial operation, and there was abnormal noise and jamming, which caused equipment failure.

7. The site is oily and slippery, making slips and falls easy.

3. Preparation before operation

1. Personnel preparation

All operators must hold a certificate to work, be familiar with the structure of the monkey car, the principle of the reducer and the content of this measure, and all employees must sign and implement it before operation. The on-site safety person-in-charge, operator, and guardian should be clearly defined and the division of labor should be clear. Unlicensed and illegal operations are strictly prohibited.

2. Equipment tool preparation

Prepare wrenches, sockets, copper rods, rubber hammers, special oil seal disassembly and assembly tools, clean rags, dust-free cotton gauze, oil barrels, reducer lubricating oil of the same type, sealant, warning signs, and locking devices.

All tools are in good condition, with no cracks or slippage, and the measuring tools are qualified.

3. Material preparation

Use the original qualified oil seal of the same specification and model. The oil seal has no aging, no deformation, no cracks, and the lip is intact. It is strictly prohibited to use non-standard and inferior accessories.

4. Site environment preparation

Clean the debris, dust and oil in the working area of the machine head to ensure that the working space is unobstructed; set up warnings in the working area to prohibit entry by unrelated personnel.

4. General safety regulations

1. Strictly implement the power outage, power inspection, lockout, and tag-out system, and implement the principle of "whoever cuts off power, who delivers power, who tags out, and who delists".

2. The whole monkey car is shut down, the main power supply is cut off, the switch is locked, and a warning sign "Equipment maintenance, closing is prohibited" is hung.

3. During the maintenance period, it is strictly prohibited for anyone to operate the console buttons and switches.

4. It is strictly prohibited to extend body parts into gears, couplings, and transmission rotating parts during operation.

5. Handle all disassembly and assembly operations with care. Do not pry or smash hard to damage the equipment joint surface and journal.

6. The entire operation must be supervised by a dedicated person, and the guardian is not allowed to leave or skip work.

5. Specific construction technology and technical requirements

1. Shut down and power off

Stop the operation of the overhead passenger device, press the emergency stop button, disconnect the main power supply and control power supply of the equipment, check the electricity and confirm that there is no power, then lock and tag out.

2. Pressure relief and oil drain

Let the equipment cool down, place an oil bucket at the oil drain port of the reducer, slowly drain out the internal lubricating oil, recover and save it. If there are no impurities, it can be filtered and reused. If the pollution is serious, replace all the oil with new oil.

3. Remove end cover bolts

Loosen the fixing bolts of the reducer oil seal end cover diagonally, in stages, and evenly. It is strictly forbidden to remove the end cover of the reducer at one time to prevent the end cover from deforming and the bearing force deviation. After all the bolts are removed, use the jack screw holes to push out the end cover evenly. It is prohibited to violently pry the joint surface.

4. Remove old oil seal

Use special oil seal hooks and pry tools to pull out the oil seal evenly from the outside. It is prohibited to pry obliquely or hard to damage the journal, sealing groove, and box contact surface.

After removing the old oil seal, thoroughly clean the aging glue, sludge, iron filings, and impurities in the tank.

5. Cleaning of sealing surface and journal

Use dust-free cotton gauze and cleaning agent to thoroughly wipe the journal, oil seal installation groove, and end cover sealing surface to ensure there is no oil, no particles, and no burrs.

Check that the journal has no scratches, grooves, or lint. If there is any minor damage, it needs to be polished to avoid wear and leakage of the new oil seal lip.

6. New oil seal installation

(1) Apply the same type of lubricating oil and a small amount of oil-resistant sealant evenly to the lip and outer ring of the new oil seal.

(2) The lip of the oil seal faces the oil chamber side, and reverse installation is strictly prohibited.

(3) Use a special sleeve and rubber hammer to press in vertically, evenly, and slowly, keeping it level throughout the process without tilt, jamming, or deformation.

(4) The oil seal is pressed in place and fits flatly without looseness or offset.

7. End cover reset and tighten

The end caps are aligned and fit smoothly, and the bolts are tightened evenly and diagonally with moderate and uniform force to prevent the end caps from being deformed and causing lax sealing.

8. Add lubricating oil

Add lubricating oil specified by the original manufacturer according to the standard oil level of the equipment. The oil level should be between the upper and lower scales of the oil mark and should not be too high or too low.

6. Completion inspection

1. Inventory tools and accessories. No tools or debris are left inside the equipment or in the working area.

2. Check that all bolts are tightened in place and the end caps fit tightly.

3. After several turns of manual turning, the machine can rotate flexibly, without any jamming, abnormal noise or bias.

4. Check that there is no oil leakage, leakage, or abnormal extrusion marks at the oil seal position.

7. Safety measures for trial operation

1. Confirm that all personnel have evacuated from the rotating parts and equipment operating range.

2. Remove the warning sign, release the lock, and power on and run 30 for more than 1 minute without load.

3. Observe the operation of the reducer: there is no abnormal sound, no vibration, no abnormal heating, and no leakage of the oil seal.

4. Only after the trial operation is normal, the normal manned operation of the overhead passenger device can be resumed.

8. Quality standards

1. The oil seal is installed correctly, in place, without skew or damage.

2. The sealing surface is tight and there is no oil leakage, oil leakage or oil throwing during operation.

3. The reducer runs smoothly with no abnormal noise and no abnormal temperature rise.

4. The oil level is standard, the lubrication is good, and the equipment is restored to good condition.

9. Safety precautions

1. It is strictly prohibited to operate with electricity, pressure, or equipment residual pressure.

2. It is prohibited to pry the journal and sealing surface with iron tools during the entire disassembly and assembly process to avoid permanent damage.

3. It is strictly forbidden for debris, dust and iron filings to enter the inside of the reducer.

4. During the trial operation, personnel are strictly prohibited from approaching the coupling, transmission wheel, and rotating parts.

5. The site must be cleaned up after the operation is completed, so that the work is completed, materials are used up, and the site is cleared.

10. Emergency measures

1. Sudden calls and equipment changes during operation: Stop the operation immediately, evacuate personnel, lock and tag out again, and investigate the cause.

2. If the journal is damaged or the oil seal installation fails: Stop the operation immediately, report to the team, and formulate remedial measures.

3. If abnormal noise, jamming, or oil leakage occurs during trial operation: stop the machine immediately, cut off the power, and re-inspect and handle it. It is strictly prohibited to operate while sick.

(Source: Coal Mine Safety Information)