PVC pipe extruder extrusion problems and solutions (Ⅱ)

6. The inner wall of the PVC pipe is not flat

reason:

1. The main reason for the irregular depression of the inner wall is insufficient melting

2. The regular raised "pimples" on the inner wall are mainly caused by the screw temperature being too high and the rotation speed being too fast

3. The die temperature of the PVC pipe extrusion core is too low

Solution:

1. Increase the temperature of the main unit of the PVC pipe extruder, increase the temperature of the main unit, increase the rotational speed, and promote melting

2. Reduce the temperature of the main engine and the speed of the screw

3. Increase the core mold temperature

7, PVC pipe is brittle

reason:

1. Insufficient degree of plasticization

2. The screw speed of the PVC pipe extruder is too fast

3. The temperature of the head of the PVC pipe extruder is too low

4. Resin viscosity is too high

Solution:

1. Adjust the temperature of the host to ensure plasticization

2. Reduce the screw speed

3. Adjust the heating ring of the machine head to increase the temperature

4. Choose low viscosity resin or add a small amount of low viscosity resin

8, the pipe is broken

reason:

1. The pulling speed of the PVC pipe extruder is too fast

2. There are impurities in the material

3. The mixture is unqualified

Solution:

1. Reduce towing speed

2. Replace impurity-free materials

3. Check whether the mixing process is wrong and whether the operation or formula is reasonable

9, the thickness of both ends of the finished product is uneven

reason:

1. The temperature of the sizing jacket water is too high

2. The compressed air pressure is too high

3. The cutting speed is too slow

4. The traction speed is unstable, fast and slow

Solution:

1. Increase the cooling water volume of the outer wall of the sizing sleeve to improve the cooling effect

2. Reduce stress

3. Adjust the cutting speed

4. Check the traction machinery and equipment, and correct the traction speed

10. "Shark skin disease" appears on the surface of the pipe

reason:

The pulling speed of the PVC pipe extruder is too fast, which often occurs in the production of thin-walled pipes with excessive stretching (excessive stretching ratio)

Solution:

Reduce the pulling speed of the PVC pipe extruder, reconfigure the core die, and try not to use the method of drawing thin-walled pipes to produce low-pressure pipes