Extruded pipe often appear defects and improve the reasons

Abnormal phenomenon

The reasons causing

The solution

Surface without shiny

①die temperature is too low  ②die wall does not dryor  ③net compressed air supply is insufficient or leakage

①appropriate to improve the temperature  ②clean up the die ③increase the gas supply or check the leak and repair

Thickness is not uniform

①core mold and die position is not correct ②plasticizing uneven ③traction is not normal ④compressed air instability ⑤diehead temperature instability

①should adjust the core mold and die center position ②check the traction device ③should be a smooth supply system ④strengthen the control of the plasticizing system ⑤check the head section heating device is intact, and the nose temperature stability

Surface has the black lines

①the raw material additive is unevenly dispersed ②raw material poor liquidity ③head section and filter temperature too high ④head section filter and shunt version of the poor structure ⑤the filter is not clean

①improve the mixing, strengthen the mixing to improve the dispersion performance ②to improve the raw material formula ③appropriate to reduce the temperature ④check the filter and shunt plate ⑤clean up the filter

Surface wrinkles and ripples

①die temperature is too high or uneven heating ②cooling stereotypes lack of water supply, the water temperature is higher ③traction speed is too slow ④die output is not uniform

①check the heating device is damaged, reduce the temperature appropriate ② increase the water supply ③speed up the traction ④ adjust the die gap

Inner wall crack

①raw material mixed with impurities ②core mold temperature is low  ③low cylinder temperature ④traction too fast ⑤too much lubricant

①to pretreatment of raw materials ②increase the core mold temperature ③ improve the cylinder temperature ④slow down the traction speed ⑤ adjust the formula