What are the main failure modes of belt drives? What are the design guidelines for belt drives

The main failure modes of belt drive are fatigue damage and slippage of the belt, such as delamination, tearing and breakage.

The design criterion of the belt drive is to ensure that the belt drive has a certain fatigue strength without slipping.

and longevity. Causes of failure of belt drives:

1. When the conveyor belt is rolled into the drum, it will bend, and when the number of bends reaches its fatigue limit, bending damage will occur, and small cracks will appear in the initial stage, and over time, the cracks will expand or tear, which will eventually lead to the breakage of the conveyor belt and cause the failure of the belt drive.

2. Due to the processing error of the drum itself, the diameter change caused by the material sticking to its surface or uneven wear and tear, and the traction of the conveyor belt.

Under the action of the moving component, the conveyor belt produces deviation in the direction of the larger diameter of the pulley, and the conveyor belt will deviate to the upper part, resulting in the failure of the belt drive.

Extended Materials. First, the design points of belt drive.

1. The transmission system should meet the functional requirements of the machine, and the performance is excellent and the transmission efficiency is high.

2. The structure is simple and compact, occupies little space, is easy to operate, safe and reliable.

3. Good manufacturability, processing cost and convenient maintenance.

4. Do not pollute the environment.

Two. Features of belt drive.

1. The transmission is accurate, there is no slippage when working, and it has a constant transmission ratio.

Belt drive. Sogou Encyclopedia - Transmission: Belt Transmission.

The main failures are abrasion, gluing, pitting, and tooth breakage. The worm drive is designed according to the contact fatigue strength, and the bending strength of the tooth root is checked.

Failure modes of belt drives: slippage and fatigue failure.

Design criteria: Under the condition of ensuring no slippage, the belt drive has a certain fatigue strength and life.

There are 5 types of failure modes for chain drives. There are mainly fatigue breakage of chain plates, impact fatigue damage of rollers and sleeves, gluing of pins and sleeves, wear of chain hinges, and overload breakage. In order to improve the stability of the movement of the chain drive and reduce the dynamic load, it is better to have more teeth for small sprockets.

However, the number of small sprocket teeth should not be too much, otherwise the chain drive will fail to skip teeth earlier.

Advantages of chain drivesChain drive has many advantages, compared with belt drive, there is no elastic sliding and slipping phenomenon, the average transmission ratio is accurate, the work is reliable, and the efficiency is high; The transmission power is large, the overload capacity is strong, and the transmission size is small under the same working conditions. The required tension is small, and the pressure acting on the shaft is small; It can work in harsh environments such as high temperature, humidity, dust, and pollution.

Failure modes of belt drive: tooth surface gluing, tooth surface wear, gear tooth breakage, tooth surface plastic deformation, tooth surface pitting.

Design criteria for belt drive: When designing gear drive, it is usually calculated only according to the two criteria of ensuring the bending fatigue strength of the tooth root and ensuring the contact fatigue strength of the tooth surface. For high-speed and high-power gear transmission (such as aero engine main drive, steam turbine generator set transmission, etc.), it is also calculated according to the criterion of ensuring the anti-gluing ability of the tooth surface.

As for the ability to resist other failures, although they are generally not calculated at present, measures should be taken to enhance the ability of gear teeth to resist these failures.

The main failure modes of belt drives are slippage and fatigue failure.

1. Belt fatigue fracture. The stresses on either cross-section of the belt will change cyclically as the belt runs. When the stress cycle reaches a certain number of times, that is, after a certain period of operation, fatigue cracks and delamination occur locally, and then a loose state or even fracture occurs, resulting in fatigue damage and loss of transmission capacity.

2. Skidding. When the working external load exceeds the maximum effective tensile force of the belt drive, the belt and the small pulley slide relative along the entire working face, and the movement and tension cannot be transmitted, resulting in the slippage failure of the transmission.

3. Belt transmission is a kind of mechanical transmission that uses a flexible belt tensioned on the pulley for movement or power transmission. Depending on the transmission principle, there is friction between the belt and the pulley.

There is also a friction belt transmission for transmission, and there is also a synchronous belt transmission for intermeshing transmission between the belt and the teeth on the pulley.