To prevent fatigue damage to the steel wire rope of European wire rope electric hoists, comprehensive measures need to be developed from four aspects: design selection, operation specifications, maintenance, and environmental control. The specific measures are as follows:

1、 Reasonable selection and installation

Match working condition requirements

Select wire rope specifications based on load type (such as static, dynamic, impact load), operating frequency (such as lifting frequency per hour), and operating environment (such as temperature, corrosiveness).

Priority should be given to using wire or surface contact steel wire ropes with good fatigue resistance to avoid point contact steel wire ropes being prone to breakage due to local stress concentration.

Optimize the design of the winding system

Ensure that the ratio of the diameter of the drum and pulley to the diameter of the steel wire rope meets the standard (e.g. drum diameter ≥ 20 times the diameter of the steel wire rope), and reduce bending stress.

The groove type of the pulley should match the steel wire rope to avoid additional wear caused by deflection or jamming.

Correct installation and tensioning

Maintain the free sag of the steel wire rope during installation to avoid excessive stretching or twisting.

Adjust the brake clearance to ensure even force on the steel wire rope during load lifting/lowering.

2、 Standardize operational behavior

Avoid overloading and impact loads

Strictly control the use within the rated load range, and prohibit sudden loading or unloading (such as free fall of heavy objects).

The diagonal angle should not exceed 5 ° to prevent the steel wire rope from being unevenly worn in the pulley groove.

Control the lifting and lowering speed

Operate at a constant speed to avoid sudden changes in tension of the steel wire rope caused by rapid acceleration or braking.

Prioritize using brake control during descent to reduce the impact of free fall on the steel wire rope.

Reduce idle running time

When unloaded, the steel wire rope only bears its own weight, and long-term operation will accelerate fatigue. Therefore, the unloaded stroke should be shortened as much as possible.

3、 Strengthen maintenance and upkeep

Regular lubrication

Apply specialized lubricating grease (such as steel wire rope lubricating oil) to the steel wire rope every month to reduce internal steel wire friction.

Before lubrication, it is necessary to clean the surface dirt to prevent the lubricant from mixing with impurities and forming abrasive particles.

Timely replace worn parts

Wear of pulley bearings can cause the steel wire rope to deflect, and regular inspection and replacement are required.

When there are cracks on the surface of the drum or excessive wear on the rope groove, the drum should be repaired or replaced.

Monitor the status of the steel wire rope

Appearance inspection: Check the steel wire rope weekly for broken wires, rust, deformation, or looseness.

Non destructive testing: Use electromagnetic flaw detectors every quarter to detect internal broken wires and detect potential hazards in advance.

Scrap standard:

The number of broken wires in a single strand exceeds 10% of the total number of wires;

Diameter reduction exceeding 7% of nominal diameter;

The surface rust or wear exceeds 40% of the nominal diameter.

4、 Improve the usage environment

Anti corrosion measures

In humid or corrosive environments, galvanized or stainless steel wire ropes should be selected, and protective coatings should be added.

Regularly clean the surface of the steel wire rope to prevent salt spray and chemical substances from adhering.

Control temperature and humidity

The high temperature environment will reduce the strength of the steel wire rope, and it is necessary to strengthen ventilation or install cooling devices.

Cold resistant lubricating grease should be used in low-temperature environments to prevent the steel wire rope from becoming brittle.

Reduce mechanical damage

To avoid friction between the steel wire rope and the edges or obstacles of the equipment, install a rope guide or protective cover.

Wrap neatly during storage to prevent twisting or knotting.

5、 Establish a fatigue management file

Record usage data

Count the number of lifting times per hour, load type, running time and other parameters to evaluate the degree of fatigue accumulation.

Shorten the maintenance cycle for high-frequency equipment (such as lifting more than 60 times per hour).

Develop a replacement plan

Set the service life of the steel wire rope according to the working conditions (such as 2 years in normal environments and 1 year in harsh environments), and replace it in advance.

Implement a mandatory scrapping system for key equipment such as nuclear power plants and high-rise building hoisting.

6、 Training and supervision

Operator training

Regular training on fatigue damage identification methods for steel wire ropes (such as wire breakage location and corrosion characteristics).

Emphasize the importance of standardized operations in extending lifespan.

On site supervision and assessment

Install a monitoring system to record operational behavior and impose penalties for violations such as overloading and diagonal pulling.

Include the status of the steel wire rope in the equipment health management assessment indicators.

The main equipment produced by Hebei Makita: stage electric hoist, electric chian hoist, wire rope electric hoist，Hand chain hoist, lever hoist, pneumatic hoist and other lifting equipment