The differences in maintenance methods between flat slings and flexible slings

As the core tool for lifting operations, the maintenance method of lifting slings directly affects their service life and operation safety. Jiangsu Dongfang Lishen Lifting Equipment Co., LTD., drawing on industry experience and technical standards, analyzes the maintenance differences between flat slings and flexible slings from three dimensions: cleaning and maintenance, damage inspection, and storage environment.

Cleaning and maintenance: The material properties determine the cleaning method

Flat slings are usually made of polyester or polypropylene, with a smooth surface but prone to dust and oil stains. When cleaning, use neutral detergent (such as soapy water) in combination with a soft-bristled brush. Avoid using acidic or alkaline cleaners to prevent fiber corrosion. For instance, after hoisting acid and alkali goods at the port, they should be immediately rinsed with clean water and naturally dried to prevent the residue of chemical substances from causing the fibers to become brittle.

The outer layer of the flexible sling is wrapped with a wear-resistant sheath (such as nylon or polyester), and the inside is a continuously wound synthetic fiber core. The key to cleaning lies in the surface of the casing. It can be wiped with a damp cloth and then air-dried naturally. Soaking or high-temperature drying is strictly prohibited. For instance, in the installation of wind power equipment, if the flexible slings are contaminated with lubricating oil, they need to be locally treated with a special degreaser to prevent the oil from penetrating into the fiber core and affecting its strength.

Storage environment: The requirements for temperature and humidity control are different

Flat slings should be stored in a dry and well-ventilated warehouse to avoid direct sunlight which may cause fiber aging. When storing, it should be laid flat or rolled up. Folding is strictly prohibited to prevent creases. For instance, when chemical enterprises store flat slings, they need to separate acidic and alkaline substances to prevent environmental corrosion.

Flexible slings have higher requirements for the storage environment, and the temperature and humidity need to be controlled at 20℃±5℃ and the relative humidity ≤60%. If exposed to a damp environment for a long time, the fiber core is prone to absorbing moisture and expanding, resulting in a decrease in strength. For instance, when wind power enterprises store flexible slings, they need to be equipped with dehumidification devices and regularly turn the sling body to prevent local moisture.

Maintenance cycle and tool differences

Flat slings are recommended to undergo a comprehensive maintenance every 50 uses or every 3 months. Maintenance tools include soft brushes, neutral detergent, thread detectors, etc. Flexible slings should be inspected every 30 uses or every two months. Special attention should be paid to observing the micro-cracks in the sleeve with a magnifying glass, and a tension tester should be equipped to test the strength of the fiber core.

The correct maintenance method can extend the service life of lifting slings by 30% to 50%. The company can provide customized maintenance solutions, covering flexible lifting slings ranging from 0.5 tons to 3,000 tons and flat lifting slings from 1 to 50 tons, and is equipped with professional testing equipment to help customers achieve safe and efficient lifting operations.