During the use of elevator wire ropes, with the natural elongation of the elevator wire ropes, the force of each rope is different, and the tension deviation of each wire rope (generally 4-7) will exceed 5%, which is out of tolerance.
For newly installed elevators, as the running time increases, the wire ropes will naturally extend. Theoretically, the elongation of the traction wire rope is about 0.5%. For the general low-rise elevators, the impact is not too great, but for the high-rise elevators, especially the 2:1 suspension elevator, the impact cannot be ignored.
For example: a 14-story passenger elevator, the traction wire rope length is about 50m, such as 2:1 suspension, the rope length is about 100m, and its 0.5% elongation is as much as 500mm. We know that the buffer distance of the hydraulic buffer is 200-350mm, and the buffer distance of the spring buffer is 150-400mm. With the natural elongation of the traction wire rope, the leveling accuracy will change. Some elevators can automatically re-level, but most elevators require maintenance workers to re-adjust the leveling accuracy to meet the GBl0060-93 leveling accuracy. Requirement, in this way, the elongation of the traction wire rope will inevitably extend to the counterweight side, causing the counterweight side buffer distance to become smaller and smaller. In the end, the buffer distance may be too small to exceed the tolerance, and even in severe cases. The counterweight has slipped onto the buffer before the elevator goes up to the leveling floor, causing an elevator failure.
①When installing the elevator wire rope, the counterweight side buffer distance should be as close as possible and the upper limit should be larger. Once the traction wire rope is extended, it can be compensated by itself;
②When installing, the adjusting nut of the rope end plate of the traction elevator wire rope should have an adjustment margin of about 100mm for the maintenance worker to adjust;
③The counterweight base should be equipped with 3 adjustment blocks (each adjustment block is about 120mm high). When the buffer distance becomes smaller, the maintenance worker can remove 1 to 3 adjustment blocks according to the situation;
④If there is no adjustment block on the counterweight base and the adjustment nut of the rope end plate cannot be adjusted, then the steel wire rope has to be re-cut and the rope end is redone (you can change one by one, without lifting the car and supporting the counterweight).