Analysis of normal wear fracture and abnormal fracture of PVC screw
1. The screw is normally broken:
The screw is a vulnerable item in the extrusion process. The amount of calcium powder added is different, and the life of the screw is different. Generally, the screw life of 100 parts of calcium and below is 1-2 years, and the screw life of 100-200 parts of calcium is In about 1 year, the screw life of 200-300 parts of calcium is 6-8 months, and the screw life of 300 parts of calcium or more is 3 months. Of course, the choice of calcium powder is also very important, light calcium is very obvious, the specific gravity of calcium can extend the life of the screw. If the screw wear is severe, the break is normal!
2. Non-normal break of the screw:
<1> Damage to the distribution box bearing causes the screw to break.
Analysis of the cause: bearing aging or its own quality hazard.
Solution: Replace the bearing.
Eliminate the method: check the distribution box from time to time, especially if the sound is abnormal.
<2> The heating temperature is insufficient to cause the screw to break.
Cause analysis: Line problem or heating ring damage
Solution: Check the line or replace the heating ring.
Eliminate the method: carefully check the temperature of each zone before starting the machine, and check the temperature of each zone regularly during the production process.
<3> The interruption of the production process causes the screw to break.
Analysis of the reason: the material in the hopper is not properly fed in time.
Solution: Hopper plus stirring device.
Eliminate the method: regularly check the spring material or the material in the spiral hopper, and add the alarm device inside the hopper.
<4> A problem with the formulation caused the screw to break.
Analysis of the cause: Formulation personnel mistakes caused formula errors.
Solution: Mix carefully according to the formula.
Eliminate the method: check the host current from time to time, carefully observe the machine running state when changing the formula.
<5> Foreign matter in the raw material causes the screw to break.
Analysis of the cause: foreign matter in the raw material causes the screw to become stuck
Solution: Put the magnetic flux on the discharge port.
Eliminate the method: irregularly clean the impurities on the strong magnetic surface.
Summary: In summary, most of the screw fractures are caused by these reasons. As long as these problems can be eliminated, I believe that the probability of your screw breaking will be much lower.
