Multi strand fiber ropes (woven from multiple strands of fibers, common materials include polyester, nylon, polypropylene, etc.) are commonly used in construction for lifting, traction, safety ropes, and other scenarios. The performance characteristics and maintenance points are as follows:

1、 Core material characteristics and applicable scenarios of multifilament rope

1. Material characteristics

High flexibility and toughness: Made by twisting or weaving multiple strands of fine fiber filaments, it is soft and easy to bend, suitable for bypassing complex shaped components (such as steel pipes and steel bar nodes), and not easy to damage the surface of the suspended object.

Lightweight: Under the same diameter, the weight is only 1/4~1/5 of the steel wire rope, making it easier to carry and operate in high-altitude operations (such as external wall construction basket towing ropes).

Chemical corrosion resistance: Synthetic fibers such as polyester and nylon are resistant to general acidic and alkaline solutions, making them suitable for humid or slightly corrosive environments (such as basement lifting and contact with concrete slurry).

Elastic buffering: Fiber materials have a certain degree of elasticity and can absorb slight impact loads during lifting (such as reducing vibration damage when lifting glass curtain walls or precision instruments).

2. Typical applications in construction

Lifting lightweight components: horizontal or vertical lifting of aluminum alloy templates and small prefabricated parts (≤ 2 tons).

Safety protection rope: used for hanging safety belts and temporary handrails for high-altitude operations (flame retardant multifilament rope that meets safety standards should be selected).

Traction and binding: fixing scaffold members, pulling cables or temporary facilities (such as positioning ropes during scaffold erection).

Special environmental operations: Replace steel wire ropes in construction sites with explosion-proof requirements (such as chemical factory renovation projects) to avoid sparks caused by metal friction.

2、 Correct usage specifications for multifilament ropes

1. Load and connection requirements

Clear permissible load:

Check the minimum breaking force on the product label, and the actual load should be controlled within 1/6~1/8 of the breaking force (safety factor ≥ 6). For example, for a double wire rope with a breaking force of 24kN, the maximum lifting weight per rope is recommended to be ≤ 3 tons.

Attention: The strength of nylon rope will decrease by 10% to 15% after being dampened, and the load should be reduced when used in humid environments.

Connection method:

Priority should be given to using specialized rope buckles, shackles, or fiber hoists to avoid direct knotting (knotting can reduce local strength by 30% to 50%);

If knotting is necessary, low damage knotting methods such as flat knots and Brin knots should be used, and the knot head should be checked for firmness after being subjected to force.

2. Operation taboos and protection

Avoid high temperatures and open flames:

The melting point of fibers is relatively low (such as polyester fibers with a melting point of about 255 ℃), so it is necessary to stay away from heat sources such as welding sparks and cutting flames, and maintain a safe distance of ≥ 2 meters during operation.

Prevent sharp angle wear:

Rubber pads, waste tire skin, or fiber protective covers should be added at the contact between ropes and metal components, especially when lifting materials with sharp edges such as angle steel and channel steel (which need to be scrapped if the diameter decreases by ≥ 10% due to wear).

Overloading and sudden pulling are prohibited:

During the lifting process, avoid sudden acceleration or emergency stop to prevent excessive elastic deformation from causing fiber breakage (instantaneous impact may cause the load to exceed twice the rated value).

3、 Key points for daily maintenance and inspection

1. Cleaning and maintenance

Regular cleaning:

Rinse the mud and oil stains on the surface of the rope body with clean water every week, and wipe it with a soft cloth after drying (if there is concrete slurry, it should be removed before hardening to avoid fiber wear after solidification);

Oil stains can be diluted with neutral detergent (such as dishwashing detergent) and wiped clean. It is strictly prohibited to use solvents such as gasoline and alcohol (which may corrode fibers).

Lubrication and protection:

Apply special protective agent for fiber (such as silicon based lubricant) on the surface of rope body every 2 months to enhance the anti ultraviolet and anti-aging performance and slow down the fiber embrittlement;

When stored outdoors, cover with waterproof canvas to avoid direct sunlight (UV rays can cause the strength of nylon ropes to decrease by 20% within 3 months).

2. Comprehensive inspection cycle

Daily visual inspection:

Observe whether there are any abnormalities such as broken wires, fuzzing, discoloration (such as yellowing or blackening), local swelling, etc. on the rope body, and focus on checking the stress points and rope buckle connections;

Shake the rope to check for loose or broken strands inside (stop immediately if you hear any abnormal noise).

Monthly in-depth inspection:

Measure the diameter with a vernier caliper. If the wear exceeds 15% of the nominal diameter, it should be downgraded for use;

Load test the suspected damaged area (such as conducting a static load test with 50% of the rated load to observe for significant elongation or deformation).