Belt conveyor is a kind of continuous action conveyor with belt as traction mechanism bearing mechanism. It has the advantages of large transportation capacity, low working resistance, low power consumption, simple maintenance so on. It is widely used in coal mine surface underground transportation. Drum is the main component of belt conveyor. The service life of the drum seriously affects the normal operation production of the conveyor.

1. Structure working principle of roller

The roller in the conveyor can only transfer the traction, but also change the running direction of the belt. According to the manufacturing process, it is divided into welding roll casting welding roll, driving roll reversing roll. High power (≥ 360kw) drive roller adopts casting welding roller, the rest can use welding roller. The drum is composed of a shaft, a reel two connecting plates. The receiving disc is a casting the reel is made of steel plate. In operation, the shaft is connected to the receiving plate, the receiving plate is welded to the disk, the driving force is transmitted to the roller shaft, the shaft drives the overall movement of the roller, thus driving the belt to run. Based on the principle of friction between the transmission device the conveyor belt, the reliable transmission of energy is ensured. Conveyor belt.

2. Analysis of the causes influencing factors of drum cracking

(1) Cause analysis of fracture

The belt has a lot of pressure on the drum. It is easy to crack the drum under high pressure for a long time. Cracks usually run the welded web on one side to the welded web on the other. The main reasons for fracture: first of all, the belt tension, because the tension traction. In order to improve the transmission capacity of the conveyor, we always hope to achieve the goal by increasing the tension, which is bound to increase the pressure of the roller. In addition, with the increase of rotation speed, the torque acting on the idler will also increase, which will lead to the bending deformation of the idler its parts, the harsh underground environment will lead to the fracture of the idler; the second reason is that the roller is strong enough, the selected steel plate will also cause cracks if the material is good the thickness of the steel plate is enough. Third, the steel plate welding process is good, welding quality is high, also can cause cracks. Because the structure of the roller is closely related to welding, welding stress will be produced in the process of operation. If the treatment is good, the weld will crack rapidly under pressure.

(2) Several factors affecting drum cracking

The abrasion of the roller leads to the decrease of strength the fracture of the roller. The main influencing factors are as follows: 1. The wear caused by coal dust dust crushing on the surface of belt roller is typical abrasive wear. That is, the wear caused by these chips usually produces special chips pits on the damaged roller surface. At the same time, fatigue effect occurs due to surface impact. In addition, due to the chemical action of liquid gas medium, especially the influence of high temperature, the wear is intensified, so that the strength of the roller is reduced. ② The influence of wrap angle on wear is discussed. The increase of wrap angle will increase the traction of the roller surface reduce the wear, but the wrap angle is easy to be too large, otherwise it will increase the bending fatigue damage of the belt; ③ the influence of friction coefficient on the wear. Increasing friction coefficient is a way to reduce wear. At present, people are looking for materials with high friction coefficient, stable performance, wear resistance high specific pressure. The material is used as lining for the drum.

The belt conveyor has the advantages of strong conveying capacity, long conveying distance, simple structure, easy maintenance, easy program control automatic operation. The continuous intermittent movement of the conveyor belt is used to transport articles under 100 kg powdery granular articles. It is fast, stable, low noise, can move up down the slope.