Traction steel wire rope, also known as traction rope, is a specialized steel wire rope for elevators that connects the car and counterweight, and is driven by a traction machine to lift and lower the car. It carries the total weight of the car, counterweight, rated load capacity, and other components. The traction machine wraps around the traction wheel and guide wheel in the machine room, with one end connected to the car and the other end connected to the counterweight device.
Structure and Material Requirements for Traction Steel Wire Rope
Traction steel wire rope is generally a circular stranded structure, mainly composed of steel wire, rope strands, and rope core. The steel wire rope strand is made up of several twisted steel wires, which are the basic strength unit of the steel wire rope; A steel wire rope with the same diameter per strand twisted from steel wire has a higher fatigue strength when there are more strands. Elevators are usually equipped with 6 or 8 shares. The rope core is a flexible core rod wrapped by rope strands, usually made of synthetic fibers such as sisal or polyolefin (polypropylene or polyethylene), which can support and fix the rope and store lubricants. The material of the steel wire in the steel wire rope is made of high-quality steel with a carbon content of 0.4% to 1%. In order to prevent brittleness, the content of impurities such as sulfur and phosphorus in the material should not exceed 0.035%.
Guidelines for Replacing Steel Wire Rope
Generally, the following four aspects can be considered: a large number of broken steel wire ropes. Wear and tear occur and develop simultaneously with the fracture of steel wire ropes. Surface and internal corrosion, especially internal corrosion, can be inspected using a magnetic flaw detector. The use of steel wire rope has been quite long. Of course, it cannot be generalized based on the frequency of use. Generally, the safety period should be at least one year. If it has been used for 3-5 years, it is worth considering. To correctly determine the time, it is also necessary to analyze and judge from the records of regular inspections. Broken wires are evenly distributed between each strand of the rope. The maximum number of broken wires within one twist length exceeds 32 (approximately 20% of the total number of wires in the steel wire rope). The broken wires are concentrated in one or two strands of rope. The maximum number of broken wires within one twist length exceeds 16 (approximately 10% of the total number of wires in the steel wire rope). After the traction rope is worn, its diameter is less than or equal to 90% of the nominal diameter of the original steel wire rope. The steel wire on the surface of the traction rope has significant wear or corrosion.
