To prevent the conveyed material from staying at the bottom of the pipeline, the pneumatic conveying device must keep the material moving at a certain speed. There will be collisions and impacts between the material particles in the transfer and the pipe wall, which is the cause of wear and tear of the conveying pipe in the pneumatic conveying device. The wear in the straight pipe section of the pneumatic conveying pipe is very light. The easy-to-wear parts mainly occur at the bends of the pipes, especially when the solid particles impact the outside of the bends of the pipes, which is elbow wear.
Factors caused by pipe wear 1. Friction or rolling wear: surface wear caused by material friction. 2. Scratch wear: Local peeling occurs due to the material going deep into the surface. 3. Impact wear: The surface tissue is partially broken and detached due to the impact of the material.
The greater the roughness of the elbow, the greater the frictional resistance, and the easier the elbow is to wear. Usually the material with less roughness is selected at the elbow; too many elbows are used. The greater the energy consumption, the easier the pipeline is blocked and the faster the wear of the elbow; the smaller the pipe diameter. The greater the resistance to the airflow. The more damaged the pipe wall; the greater the bending angle. The greater the amount of wear.
The elbow is the most vulnerable part when conveying abrasive materials. When the material passes through the elbow, it hits the inner wall outside the pipe due to centrifugal force and inertia. Some particles slide along the inner wall outside the pipe wall; another part of the particles reflect from the outer inner wall to the inner wall inside the pipe. This repeated movement: the material undergoes several collisions. In the middle of the outer wall of the circular section elbow, a pit like a chisel will be produced. Therefore, the impact and friction of the material on the pipe wall is the main reason for the wear of the elbow.
