Why use compensation chain or rope in elevator?

What is compensation chain in lift?

Compensation chain, also known as compensating ropes or balance ropes, play a crucial role in the safe and efficient operation of elevators. They are used to compensate for the weight of the elevator car and counterweight, ensuring that the tension on the hoist ropes remains constant. Here's a detailed explanation of when and why compensation chain are used in elevator systems and their working principles:-

When to Use Compensation chain: -

Compensation ropes are used in nearly all modern elevator systems, including both traction and hydraulic elevators. They are an essential component of the elevator's suspension system. The primary function of compensation ropes is to offset the dynamic loading and unloading of the elevator car as it moves between different floors. This ensures that the tension in the hoist ropes remains relatively constant during operation.

To balance the weight of wire rope , the compensation chain is used. one point of the chain is fixed at the counterweight bottom part and the other end is fixed to cabin bottom part.

Why Use Compensation Ropes?

The use of compensation ropes serves several important purposes:-

1. Maintaining Tension: - Compensation ropes balance the weight of the elevator car, its occupants, and any additional loads. This prevents excessive slack or tension in the main hoist ropes as the car travels, which can lead to uneven wear, rope damage, or inefficient operation.

2. Safety: - By preventing significant variations in rope tension, compensation ropes enhance the overall safety of the elevator. They help avoid sudden jerks or jolts that could occur when the car starts, stops, or changes direction.

3. Smooth Operation: - Compensation ropes contribute to the smooth and controlled movement of the elevator car, providing a more comfortable and stable ride for passengers.

4. Rope Longevity: - Even tension on the main hoist ropes extends their service life, reducing maintenance and replacement costs.

5. Balance load :- compensation chain normally used in high rise elevator more then 10 floors. The main purpose of compensation chain, balance excessive load of main rope of elevator. Because when length of rope increase the weight of main rope also increase it cause unblance car and counterweight load when lift go to top or bottom floor.

For eg. when lift car on top floor this time counterweight at bottom have add extra load of main elevator ropes, and when car on bottom floor and counterweight on top floor this time that load of main rope shifted to car this condition have more impact when its high rise elevator so we loop one chain according to height of elevator with car bottom and counterweight bottom so it cancel the effect of unbalancing load.

Working Principle of Compensation chain: -

The working principle of compensation chain is based on Newton's third law of motion, which states that for every action, there is an equal and opposite reaction. As the elevator car with its occupants and additional loads moves within the hoistway, the dynamic changes in weight result in fluctuations in the tension of the main hoist ropes.

Compensation ropes are usually attached to the bottom of car and looped to counterweight bottom These chain are typically lighter than the main hoist ropes, and their length is adjusted so that they are under tension when the elevator car is at rest or near its average position. When the elevator car moves, the compensation chain move with car and counterweight.

In summary, compensation ropes are an integral part of an elevator's suspension system, ensuring even tension in the main hoist ropes throughout the elevator's operation. This not only enhances safety but also contributes to a smoother and more reliable ride for passengers while extending the service life of the hoist ropes.