What should be paid attention to in the maintenance of wire rope electric hoist

What should be paid attention to in the maintenance of wire rope electric hoist

1. Regular inspection
1.1 Check the wear and damage of the wire rope
The wire rope is a key component of the electric hoist, and its wear and damage are directly related to the safety and service life of the equipment. It is essential to regularly check the wear and damage of the wire rope.
Degree of wear: The wire rope will gradually wear due to friction during use. When the wear on the surface of the wire rope reaches 10% of its diameter, the wire rope should be replaced. Wear will cause the strength of the wire rope to decrease and increase the risk of breakage. For example, under the condition of frequent lifting of heavy objects, the friction between the wire rope and the drum, pulley and other components will increase, and the wear rate will accelerate. By regularly measuring the diameter of the wire rope, its degree of wear can be accurately judged.
Wire breakage: Wire breakage is an important sign of wire rope damage. If the number of broken wires in one lay length (that is, the length of one circle of the wire rope) exceeds 10% of the total number of wires, the wire rope should be replaced immediately. Wire breakage will not only reduce the carrying capacity of the wire rope, but may also cause the wire rope to suddenly break during operation, causing safety accidents. For example, during the lifting process, if the wire rope is subjected to a sudden impact or overload, it is easy to cause wire breakage. Regularly checking the wire rope for broken wires can timely discover potential safety hazards.
Deformation: The wire rope may be deformed during use, such as kinks, wavy shapes, cage-shaped distortions, etc. These deformations will affect the normal use of the wire rope and reduce its performance. For example, kinks can damage the internal structure of the wire rope, resulting in a decrease in its strength and flexibility. Wave-shaped deformation will affect the cooperation between the wire rope and the drum and pulley, and increase wear. Regularly checking the deformation of the wire rope, you can take timely measures to repair or replace it to ensure the safe operation of the equipment.
Lubrication: Good lubrication can reduce the wear of the wire rope and extend its service life. Regularly check the lubrication of the wire rope to ensure that there is a uniform lubricating oil film on its surface. If the surface of the wire rope is dry, the lubricating oil should be added in time. Lubricating oil can not only reduce the friction between the wire rope and the drum and pulley, but also prevent the wire rope from rusting. For example, in a humid environment, the wire rope is more likely to rust. Regular lubrication can effectively prevent rust and protect the performance of the wire rope.
Inspection frequency: Determine a reasonable inspection frequency based on the frequency of use and working environment of the electric hoist. For frequently used electric hoists, it is recommended to conduct an appearance inspection of the wire rope once a week; for equipment with less frequent use, it is sufficient to inspect it once a month. In harsh working environments, such as high temperature, humidity, and high dust, the inspection frequency should be appropriately increased. For example, the electric hoist used in the port terminal is prone to rust due to long-term exposure to humid sea breeze, and the inspection frequency should be appropriately increased.

2. Cleaning and maintenance
2.1 Cleaning the wire rope and the surrounding environment
Cleaning the wire rope and its surrounding environment is an important part of the maintenance of the wire rope electric hoist, which is of great significance to extending the life of the equipment and ensuring safe operation.
Cleaning the wire rope: The wire rope will be contaminated with dust, oil, metal chips and other impurities during use. These impurities will increase the wear of the wire rope and reduce its service life. Use a soft brush or clean cloth to remove dust and dirt from the surface of the wire rope, and avoid using hard tools to avoid damaging the wire rope. For oil stains that are difficult to remove, special detergents can be used for cleaning, but attention should be paid to the composition of the detergent to avoid corrosion to the wire rope. After cleaning, the moisture on the surface of the wire rope should be wiped dry immediately to prevent rust.
Clean the surrounding environment: The environment around the electric hoist will also affect the operation and maintenance of the equipment. Regularly clean the debris, dust and oil around the electric hoist to keep the work area clean. For example, in an industrial production environment, dust and oil may accumulate on the motor, reducer and other components of the electric hoist, affecting its heat dissipation and lubrication effect, and then causing equipment failure. By cleaning the surrounding environment, the erosion of impurities on the equipment can be reduced and the probability of failure can be reduced.
Cleaning frequency: Determine a reasonable cleaning frequency based on the use environment and work intensity of the electric hoist. Under normal conditions, it is recommended to thoroughly clean the wire rope once a month; in harsh environments, such as workshops with more dust, the cleaning frequency should be increased to once a week. At the same time, a simple cleaning of the environment around the electric hoist after each use can effectively reduce the accumulation of impurities.
Inspection after cleaning: After cleaning the wire rope and the surrounding environment, the wear, wire breakage, deformation, etc. of the wire rope should be checked again, as well as the operating status of other parts of the electric hoist. Through a combination of cleaning and inspection, potential problems can be discovered and dealt with in a timely manner to ensure that the equipment is always in good working condition.

3. Prevent excessive bending
3.1 Use guide devices to maintain a reasonable bending radius
Excessive bending is one of the important causes of fatigue damage to wire ropes during operation. In order to effectively prevent excessive bending, it is essential to use guide devices to maintain a reasonable bending radius.
Function of the guide device: The guide device can guide the wire rope to run along the correct path and avoid abnormal bending of the wire rope during winding and release. For example, in the lifting mechanism of the electric hoist, the guide pulley can ensure that the angle between the wire rope and the drum is kept within a reasonable range, reducing the lateral force and bending stress of the wire rope.
Determination of reasonable bending radius: According to the diameter and structure of the wire rope, the reasonable bending radius should not be less than 20 times the diameter of the wire rope. For example, for a wire rope with a diameter of 10 mm, its reasonable bending radius should not be less than 200 mm. Too small a bending radius will increase the bending stress of the wire rope, causing fatigue fracture of the fibers inside the wire rope, thereby shortening the service life of the wire rope.
Installation and adjustment of the guide device: The guide device should be installed in a suitable position to ensure that the wire rope can pass smoothly. During installation, it is necessary to make precise adjustments according to the specific structure of the electric hoist and the direction of the wire rope so that the guide device and the drum, pulley and other components are closely matched. For example, when installing the guide pulley, it should be ensured that the center line of the pulley and the center line of the drum are in the same plane, and the distance between the pulley and the drum meets the design requirements.
Regularly check the guide device: The guide device may be worn, loose or damaged during long-term use, affecting its guiding effect on the wire rope. Therefore, it is necessary to regularly check the operating status of the guide device to detect and repair potential problems in a timely manner. For example, check whether the wheel groove of the guide pulley is severely worn, whether the pulley rotates flexibly, whether the fixing bolts are loose, etc. If problems are found, the worn parts should be replaced in time or the guide device should be readjusted to ensure its normal operation.
Actual case analysis: In the production workshop of a factory, due to improper installation of the guide device of the electric hoist, the wire rope frequently bends excessively during operation. After inspection, it was found that the position of the guide pulley was offset, causing the angle between the wire rope and the drum to be too large. After readjusting the position of the guide pulley to keep the bending radius of the wire rope within a reasonable range, the service life of the wire rope was significantly extended and the stability of the equipment operation was also improved.

4. Lubrication and maintenance
4.1 Regularly lubricate the wire rope
The lubrication of the wire rope is a key link in maintenance work, and its lubrication condition is directly related to the service life of the wire rope and the operating efficiency of the equipment.
The importance of lubrication: Good lubrication can significantly reduce the friction between the wire rope and the drum and pulley, thereby reducing wear. For example, after frequent use, the wear rate of an unlubricated wire rope may be more than 30% faster than that of a well-lubricated wire rope. In addition, lubrication can prevent the wire rope from rusting, especially in humid or corrosive environments, where lubricating oil can form a protective film to isolate moisture and corrosive substances.
Lubricant selection: Choosing the right lubricant is essential for wire rope maintenance. Special wire rope lubricants should be selected, which usually have good anti-wear, anti-corrosion and anti-oxidation properties. For example, some high-performance lubricants can remain stable at extreme temperatures and are suitable for electric hoists under different working conditions. Avoid using ordinary motor oil or butter, as they may not provide adequate protection and may even cause impurities to accumulate on the surface of the wire rope.
Lubrication method: When lubricating wire ropes, special lubrication tools such as lubrication brushes or lubrication sprayers should be used. First, clean the surface of the wire rope to remove dust and old oil stains. Then, apply or spray the lubricant evenly to ensure that every part of the wire rope is covered. For longer wire ropes, lubrication can be performed in sections to ensure the lubrication effect. For example, during the lubrication process, the wire rope of the electric hoist can be slowly moved up and down to allow the lubricant to fully penetrate the internal fibers of the wire rope.
Lubrication frequency: Determine a reasonable lubrication frequency based on the frequency of use and working environment of the electric hoist. Under normal working conditions, it is recommended to lubricate the wire rope once a month; in humid, dusty or frequently used environments, the lubrication frequency should be increased to once every two weeks. For example, for electric hoists used on construction sites, due to frequent lifting of heavy objects and harsh environments, the lubrication frequency of the wire rope should be appropriately increased to ensure its performance and safety.
Post-lubrication inspection: After lubrication, the lubrication effect of the wire rope should be checked to ensure that there is a uniform lubricating oil film on its surface. At the same time, check whether the lubricant flows into the gap between the drum and the pulley to avoid equipment failure caused by lubricant accumulation. For example, if there is too much lubricant, oil accumulation may form on the drum, affecting the winding effect of the wire rope. Excess lubricant should be cleaned up in time.

5. Electrical system inspection
5.1 Check the power cord, controller and switch
The electrical system of the wire rope electric hoist is a key part of its normal operation. Regular inspection of electrical components such as the power cord, controller and switch is essential to ensure the safety and reliability of the equipment.
Power cord inspection:
Appearance inspection: Check whether the power cord is damaged, aged, cracked, etc. Damage to the insulation layer of the power cord may cause leakage, electric shock accidents or damage electrical equipment. For example, in some electric hoists that have been used for a long time, the insulation layer of the power cord may age and crack due to long-term exposure to harsh environments. Once the power cord is found to be damaged, it should be replaced immediately to ensure the safety of the electrical system.
Connection inspection: Check whether the connection between the power cord and the electric hoist is firm, and whether the plug and socket are loose or have poor contact. Loose connections will cause voltage instability, affect the normal operation of the electric hoist, and may even cause sparks and increase the risk of fire. When checking, you can gently pull the power cord to observe whether there are signs of looseness at the connection.
Controller inspection:
Appearance inspection: Check whether the outer shell of the controller is damaged or deformed. A damaged outer shell may affect the normal heat dissipation of the controller, causing overheating and damage to the internal components of the controller. At the same time, check whether the operating buttons, handles and other parts of the controller are worn or stuck to ensure the flexibility and reliability of operation.
Functional inspection: Check whether the various functions of the controller are normal, including lifting, lowering, stopping, left and right movement, etc. You can operate the controller to observe whether the actual action of the electric hoist is consistent with the operation instruction. For example, when checking the lifting function, press the lifting button to observe whether the electric hoist can lift the heavy object smoothly and whether the lifting speed is normal. If the function of the controller is found to be abnormal, it should be repaired or replaced in time.
Switch inspection:
Emergency stop switch: The emergency stop switch is an important safety device of the electric hoist. It can quickly cut off the power supply and stop the equipment in an emergency. Check whether the emergency stop switch can work normally. After pressing the switch, the electric hoist should stop running immediately, and after releasing the switch, the equipment cannot automatically resume operation and needs to be restarted to continue operation.
Other switches: Check whether other switches of the electric hoist, such as the power switch, limit switch, etc., can work normally. The power switch should be able to reliably cut off the power supply, and the limit switch is used to limit the operating range of the electric hoist to prevent the equipment from operating beyond the safe range. For example, when checking the limit switch, you can manually operate the electric hoist to approach the limit position and observe whether the limit switch can cut off the power supply in time to stop the equipment.

6. Transmission maintenance
6.1 Lubrication and inspection of transmission
The transmission is an important part of the wire rope electric hoist. Its lubrication and inspection have an important impact on the normal operation and service life of the equipment.
The importance of lubrication: The lubrication of the transmission can effectively reduce the friction between gears, bearings and other components, reduce wear and improve transmission efficiency. For example, good lubrication can reduce the wear rate of the transmission by about 50%, thereby extending its service life. At the same time, lubrication can also play a role in heat dissipation and rust prevention, ensuring that the transmission can operate normally under various working conditions.
Selection of lubricant: Special lubricants suitable for transmissions should be selected. Such lubricants usually have good viscosity, wear resistance and oxidation resistance. For example, for the gear transmission part, a gear oil with appropriate viscosity should be selected to form a stable oil film and reduce direct contact between gears. For the bearing part, high temperature resistant and wear-resistant grease can be selected to meet its different working requirements.
Lubrication method: When lubricating the transmission device, you should first clean its surface, remove old oil and impurities, and then lubricate it according to the specified lubrication points and lubrication amount. For the gear transmission part, you can use an oil gun or oil pot to inject the lubricating oil into the gearbox to ensure that the lubricating oil can fully cover the gear surface. For the bearing part, you can use a grease gun to inject grease into the bearing seat so that the grease is evenly distributed between the rolling elements and the cage of the bearing. For example, when lubricating the gearbox, you should first open the oil filling port of the gearbox and pour the lubricating oil into the gearbox until the lubricating oil reaches the specified oil level line.
Lubrication frequency: Determine a reasonable lubrication frequency based on the frequency of use and working environment of the electric hoist. Under normal working conditions, it is recommended to lubricate the transmission device once every three months; under frequent use or harsh environments, the lubrication frequency should be increased to once a month. For example, for electric hoists used in port terminals, due to their high frequency of use and harsh working environment, the lubrication frequency of the transmission device should be appropriately increased to ensure its normal operation.
Inspection content: Regularly check the operating status of the transmission device, including the wear of the gears, the operating sound and temperature of the bearings, etc. When checking the gear, observe whether there are cracks, peeling or abnormal wear on the gear surface. If the wear of the gear tooth surface exceeds 15% of its thickness, the gear needs to be replaced. When checking the bearing, you can judge whether it is operating normally by listening to the sound and measuring the temperature. For example, if the bearing makes abnormal noise or the temperature is too high, it may be that the bearing is faulty and needs to be repaired or replaced in time.
Inspection frequency: For the inspection frequency of the transmission device, it is recommended to conduct an appearance inspection once a month and a detailed operation status inspection once a quarter. During the inspection process, the inspection results should be recorded so that potential problems can be discovered in time and corresponding measures can be taken. For example, an inspection record sheet for the transmission device is established to record the time, inspection content and problems found for each inspection, so as to facilitate tracking and analysis of the operation of the transmission device.

7. Operation specifications and safety
7.1 Strictly abide by the operating procedures
The operating specifications of the wire rope electric hoist are the key to ensuring the safe operation of the equipment and extending its service life. Operators must strictly abide by the operating procedures to avoid safety accidents and equipment damage caused by improper operation.
Operator qualifications: Personnel operating electric wire rope hoists must undergo professional training and obtain the corresponding operator qualification certificate. Training content It should include the basic principles of the equipment, operating procedures, safety precautions and emergency response measures. For example, when training operators, a company combined theoretical explanations with practical operations to enable operators to master the correct operation methods of electric hoists, effectively reducing the risk of safety accidents caused by improper operation.
Pre-operation inspection: Before using the wire rope electric hoist each time, the operator should conduct a detailed equipment inspection. The inspection content includes the wear, wire breakage, and deformation of the wire rope, whether the power cord, controller, and switch of the electrical system are normal, and the lubrication and operating status of the transmission device. For example, before using the electric hoist each time, the operator of a factory will check each component of the equipment one by one according to the checklist to ensure that the equipment is in good working condition before starting the operation.
Precautions during operation:
Smooth operation: When lifting and lowering heavy objects, the operator should operate smoothly to avoid sudden starts and stops. Excessive speed and sudden braking will produce a large impact force on the wire rope and the transmission device, resulting in problems such as wire rope breakage and transmission device damage. For example, when lifting heavy objects, the electric hoist operator at a construction site slowly accelerates and decelerates to make the heavy objects rise and fall smoothly, effectively reducing the impact damage of the equipment.
Avoid overloading: Strictly abide by the rated load of the equipment and strictly prohibit overloading. Overloading will increase the tension of the wire rope, causing it to exceed the allowable stress range, resulting in wire rope breakage, and will also cause serious damage to components such as the transmission device and the motor. For example, when a company uses an electric hoist, it installs an overload limiter on the equipment. When the load exceeds the rated value, the equipment automatically stops running, effectively preventing the occurrence of overloading accidents.
Keep a safe distance: During operation, the equipment should be kept at a safe distance from surrounding personnel and objects. Avoid collisions between heavy objects and surrounding objects during operation, causing personal injury or equipment damage. For example, in the production workshop of a factory, when the operator operates the electric hoist, he always pays attention to the surrounding environment to ensure that the running path of the heavy object is unobstructed and avoid collisions with other equipment and personnel.
Post-operation inspection and maintenance: After the operation is completed, the equipment should be simply inspected and maintained. Turn off the power, clean the dust and debris on the surface of the equipment, check the lubrication of the wire rope, and relubricate if necessary. At the same time, record the operation of the equipment and the inspection results to provide a basis for the maintenance and management of the equipment. For example, after each operation, the operator of a certain company will simply clean and inspect the electric hoist, and record the inspection results in the equipment maintenance record sheet to facilitate tracking and analysis of the operation of the equipment.