PVC pipe extruder extrusion problems and solutions (Ⅰ)

In the process of plastic pipe production line, because the operator is not skilled in the process and the operation of the pvc pipe extruder, it often causes the plastic pipe to have a rough outer surface, a jitter ring inside, uneven wall thickness, and insufficient roundness. Therefore, it is necessary to adjust the process in time and eliminate the failure of the plastic pipe production line in order to improve the product quality.

1. There are corrugations on the outer surface of the pvc pipe

cause:

(1) Uneven overflow around the die of the pvc pipe extrusion machine

(2) The cooling water temperature is high

(3) The amount of water sprayed on the sizing sleeve is small and uneven

(4) The lead speed of the pvc pipe extruder is unstable

solution:

(1) Check the die electric heating coil

(2) Decrease the water temperature or increase the cooling water prison

(3) Increase the amount of water spray and clear the water spray head around the sizing sleeve

(4) Adjust the pulling speed of the pvc pipe extruder

2. There are cracks in the inner wall of the pvc pipe

cause:

(1) There are impurities in the material

(2) The temperature of the front of the fuselage or the nose is too low

(3) The core mold temperature is too low

(4) Pulling too fast

(5) Inappropriate amount of lubricant in the formula

solution:

(1) Change the raw material

(2) Increase the production and processing temperature

(3) Increase the core mold temperature

(4) Reduce towing speed

(5) Adjust the formula, or adjust the feeding ratio

3. There are lumps on the inner or outer wall of the pvc pipe (like bubbles)

reason:

(1) Too much water in the material

(2) The material is mixed with impurities or the remaining material added is not removed cleanly

(3) The body temperature is too low

(4) The temperature of the conveying section of the barrel is too high, which is not conducive to the removal of moisture by vacuum

solution:

(1) The raw materials are fully dried

(2) Remove impurities. When the remaining materials are reused, the decomposed materials and impurities must be removed.

(3) Increase the body temperature of the pvc pipe extruder

(4) Reduce the temperature of the conveying section

4. The PVC pipe wall appears coke particles or dividing lines

reason:

(1) The filter plate is not cleaned

(2) The temperature control instrument fails, and the temperature of the fuselage and nose is too high

(3) There are dead corners or scratches in the memory of the machine head

(4) The screw is worn or there is decomposed material on the screw

(5) The design of the head shunt is unreasonable, and there are dead ends

(6) The inner surface of the head of the PVC pipe extruder is rough and the material is stagnant

(7) The manufacturing cycle is too long, and the material stays in the barrel for too long

Solution:

(1) Shut down and clean the filter plate again

(2) Lower the temperature, overhaul the instrument, and check with a mercury thermometer

(3) Stop the machine to clean the head and polish it with a polishing wheel

(4) Overhaul the screw and polish

(5) Improve the head structure of PVC pipe extruder

(6) Shut down, the inner surface of the machine head is polished

(7) Increase the extrusion speed or adjust the formula

5. The outer wall of the finished product has poor gloss or half of the outer wall is bright, and half of the outer wall has poor gloss

reason:

(1) The die temperature of the PVC pipe extruder is too low

(2) The die temperature of the PVC pipe extruder is too high

(3) There are precipitates on the inner wall of the die

(4) Rough surface of sizing sleeve

(5) The center line of the PVC pipe extruder is not in line with the center of the vacuum sizing box.

Solution:

(1) Raise the die temperature of PVC pipe extruder

(2) Properly reduce the die temperature of PVC pipe extruder

(3) Clean the die and remove the precipitate

(4) Rational sizing sleeve

(5) Adjust the center of the vacuum sizing box not in a straight line.