The reason is :

1.screen mesh is blocked.

2. the humidity of material is high.

3. the screen feeding is heterogeneous.

4. the loading material in the screen is too thick.

5. screen’s tensile is slack, and the transmit belt is too loose.

The way to resolve the problem

1.alleviate the load and clean the screen surface.

2.change the screen box angle.

3.adjust the screen machine feeding .

4. reduce the feeding capacity.

5.tighten the screen and transmit belt.