Reasons for the wear and tear of the drive belt of the bus air-conditioning compressor

As a tool for power transmission between the engine and air-conditioning compression of the traditional bus and hybrid bus, the belt will have some wear and tear during the operating cycle, which is a normal phenomenon, but the belt breaks due to severe wear and tear needs to find out the cause and improve it.
The reason for the wear and tear of the drive belt
When the belt enters and leaves the wrap angle, due to the unequal elastic strain of the belt on both sides, the
Causes the belt to form an elastic slide at the wrap corners. Elastic sliding is one of the main causes of belt wear. Normal elastic sliding will exist during the working life of the belt, and long-term accumulation will lead to severe wear of the belt, while abnormal elastic sliding will quickly cause belt wear and even belt breakage.
When the maximum static friction ≤ the maximum effective pulling force, the transmission belt will have a phase on the pulley
For sliding, this phenomenon is called slipping, and at this time, the transmission fails. The consequence of slipping is that the wear of the belt is intensified, and the belt and the driven wheel are in an unstable state of motion. Due to long-term slipping, the friction between the belt and the pulley generates heat, and the aging of the brush rubber is added.
Belt breaks, the stress on either cross-section of the belt will cycle as the belt operates
Variety. When the stress cycle reaches a certain number of times, that is, after running for a certain period of time, the belt will appear fatigue cracks and delamination locally, followed by a loose state or even fracture, resulting in fatigue damage and loss of transmission capacity.
The second reason for the wear and tear of the transmission belt
Too much or too little belt preload will cause severe belt wear. Most of the transmission belts of bus air-conditioning compressors use auto V belts. The V belt transmission relies on the contact and compression of both sides of the belt with the belt groove to generate friction for power transmission. If the preload is too small, the friction between the belt and the pulley is too small, so that the belt is easy to slip during operation, that is, the relative movement between the belt and the pulley will be accelerated, which will accelerate the wear and tear of the belt. When the pre-tightening force is too large, the belt has better transmission efficiency, and the belt is not easy to slip during transmission. However, due to the excessive pressure between the belt and the pulley due to excessive pre-tightening force, the friction force of the belt will increase during operation, resulting in increased wear. Excessive preload will also lead to increased load on the bearing, heating and wear of the bearing.
Three reasons for the wear and tear of the transmission belt
When the power demanded by the air conditioner compressor is greater than the power that the belt can transmit, that is, the power of the belt
When the load is too large, for non-meshing V-belts, the belt will slip during work, and the slipping will cause abnormal wear and aging of the rubber, shorten the service life of the belt, and even cause the belt to break.
Four reasons for the wear and tear of the transmission belt
When the diameter of the pulley is too small, that is, the bending stress of the belt is too large, the tensile stress above the neutral layer of the belt increases, the half of the upper section of the belt is stretched and narrowed, the wedge angle of the belt becomes smaller, and the neutral layer The lower half of the section is severely compressed, and the lower half of the neutral layer of the belt will extend laterally to the working surfaces on both sides, which intensifies the friction between the working surface of the lower half of the belt and the pulley, resulting in uneven wear of the belt working surface and early fatigue .
Five reasons for the wear and tear of the transmission belt
When the pulley rotates at a low speed, due to the static tension of the belt, the beating of the belt
Slip and elastic sliding will be within the normal range and will not be significantly affected by the transmission speed. When the pulley runs at an overspeed, a large centrifugal force will be generated between the belt and the pulley, and this centrifugal force will cause the pressure between the belt and the pulley to decrease, so the friction between the two will decrease. Too little friction will reduce the elastic sliding of the belt, resulting in a large amount of slippage, which will reduce the transmission efficiency of the belt. Long-term overspeed transmission will aggravate the frictional heat between the belt and the pulley, resulting in excessive wear of the belt.
Six reasons for the wear and tear of the drive belt
Environmental factors also have a great impact on the life of V-belts. If the ambient temperature rises by 11K, the service life will be reduced by 60%. Therefore, it is necessary to pay attention to the ventilation and heat dissipation of the engine compartment. In addition, when installing the pulley, if the parallelism exceeds the required normal error range, it will cause abnormal wear on one side of the belt, and the colloid on the surface of the rope will be worn or even broken. This is to ensure the parallelism between the driven wheel and the driving wheel during installation in the workshop to reduce the amount of deviation.