How to do maintenance work for hydraulic cargo lift

As an important vertical transportation equipment in industrial plants, warehouses and other places, the safety and stability of hydraulic cargo lift directly affect the operating efficiency and personnel safety. Scientific maintenance can greatly extend the life of the equipment and reduce the failure rate.

When we usually use the hydraulic cargo lift, we must regularly check, care and maintain. For example, the transmission part should have enough lubricating oil, and the quick-wear parts must be checked, repaired or replaced frequently, and for mechanical bolts, especially parts that frequently vibrate, such as pulley bearings and lifting frame connecting bolts, check whether they are loose. If there is any looseness, it must be tightened or replaced immediately.

The following will explain the maintenance points from two aspects: the steel frame system and the hydraulic system.

Steel frame system maintenance

Appearance inspection and cleaning

Regularly check the steel frame surface for obvious signs of wear, deformation or corrosion. Before each use, the dust, debris and oil on the steel frame should be cleaned to prevent the accumulation of these pollutants and cause the steel frame to rust and affect the structural strength. For hydraulic cargo lift that are exposed to harsh environments for a long time, such as in humid or dusty workshops, the cleaning frequency should be increased.

Tightening of connecting parts

The steel frame structure consists of many connecting parts, such as bolts, nuts, etc. Since the cargo lift will vibrate during operation, these connecting parts may gradually loosen. Regularly use a torque wrench to check and tighten all connecting parts to ensure that the connection is firm. Pay special attention to checking the key nodes such as the connection point between the freight elevator guide rail and the steel frame and the platform support part to prevent safety accidents caused by loosening of the connecting parts.

Guide rail lubrication and calibration

The guide rail is the track on which the hydraulic freight elevator car runs up and down, which directly affects the smoothness of the freight elevator. At regular intervals (usually one month), apply an appropriate amount of grease to the surface of the guide rail to reduce the friction between the car and the guide rail and reduce wear. At the same time, the verticality and horizontality of the guide rails should be calibrated regularly, and the deviation should be controlled within the specified range. If the guide rails are deformed or severely worn, they should be repaired or replaced in time to ensure the smooth and safe operation of the freight elevator.

Structural stress detection

For hydraulic cargo lift that have been in service for a long time or are frequently operated with heavy loads, structural stress detection should be carried out regularly. Use professional testing equipment, such as strain gauges, to measure the stress distribution of key parts of the steel frame. Once an area where stress is concentrated or exceeds the design allowable value is found, the cause should be analyzed in time and corresponding reinforcement measures should be taken, such as adding reinforcing ribs, repairing damaged parts, etc., to prevent serious problems such as fracture of the steel frame due to fatigue.

Lifting parts checking

1. Check the heavy loading chain, if there is cracks, broken, or chain's pin falling off, if any of these occur, the chain should be replaced, the chain should be replaced every 3 years using, even the chain working in a normal condition with good performance.

2. The safety steel rope should be checked every month, the steel rope may deformation and become loose, if should be re-tight again by workers when doing the maintenance work.

3. Check if all of the steel rope wheels and chain rollers are turning in normal condition, there should be no shaking, no noise, no lag, if any parts failure, they should be replaced at the first time.

4. The chain, steel rope fixing bolt and joints should be checked during each maintenance, if there is any welding parts cracks, it should be re-welding to strengthen again.

Note:

1. Check the wear and lubrication of guide rails, screws, seal rings, rollers, bearings, steel ropes, chains, etc.

2. Add lubricating oil to the above parts to ensure their lubricity and extend the service life.

Hydraulic system maintenance

Hydraulic oil inspection and replacement

Hydraulic oil is the "blood" of the hydraulic system, and its quality and performance directly affect the working efficiency and life of the system. Check the hydraulic oil level regularly to ensure that the oil level is within the normal range. Observe the color and transparency of the hydraulic oil. If the oil becomes black, turbid or has a strange smell, it means that the hydraulic oil has been contaminated or oxidized and should be replaced in time. Under normal circumstances, the hydraulic oil needs to be replaced every 2000-3000 hours of operation or about half a year, and the filter should be replaced at the same time to ensure the cleanliness of the new oil.

The oil replacement process is as follows:

1. View all hydraulic pipes and joints. Pipes must not be damaged, joints must not be loosened.

2. Remove and disassemble the lowering valve, use compressed air to blow out the impurities, then reinstall it from the beginning.

3. Drain all the hydraulic oil and take out the oil filter, clean it with compressed air, then put it back into the oil tank and connect the pipeline.

4. Replace with new oil, do not use old oil intermittently, otherwise the moving parts in the system will wear out faster.

Oil filter maintenance

The oil filter in the hydraulic system is used to filter impurities in the oil to prevent impurities from entering the hydraulic components and causing wear and failure. Regular cleaning or replacement of filters is an important part of ensuring the normal operation of the system. The coarse filter is generally cleaned every 1-2 months, and the fine filter is replaced every 3-6 months depending on the usage. When cleaning or replacing the filter, be careful to avoid impurities from entering the system to ensure a clean operating environment.

Hydraulic pump and valve component inspection

The hydraulic pump station is the power source of the hydraulic system, and the valve components are used to control the flow direction, pressure and flow of the oil. Regularly check the working status of the hydraulic pump station, such as whether the pressure and flow of the pump are stable, and whether there is any abnormal noise or vibration. For valve components, check the flexibility and sealing of the valve core. If there is leakage or insensitive movement, it should be repaired or replaced in time. At the same time, according to the recommendations of the equipment manufacturer, the hydraulic pump and valve components should be lubricated and maintained regularly to extend their service life.

Oil pipeline system inspection

Check whether the hydraulic pipeline has leakage, wear or aging. Focus on the joints, bends and welding points of the pipeline. If a slight leak is found in the pipeline, it can be repaired by tightening the joints or replacing the seals; if the pipeline is severely worn or cracked, it must be replaced in time. In addition, regularly check the fixing of the pipeline to ensure that the pipeline will not loosen or shift due to vibration during the operation of the system to avoid safety accidents.

Pressure test and adjustment

Perform pressure test on the hydraulic system regularly to ensure that the system pressure is within the specified working range. Too high pressure may cause pipeline rupture and damage to hydraulic components, while too low pressure will affect the lifting capacity and running speed of the freight elevator. According to the test results, the pressure control components such as the overflow valve are appropriately adjusted to ensure that the system pressure is stable and reliable. At the same time, the data of each pressure test is recorded to timely discover the changing trend of the system pressure and judge potential fault hazards in advance.