Extrusion Pipe Material Defect and Improvement

Abnormal phenomenon

reasons

solutions

Surface gloss

(1) mold temperature is too low ‚ (2) the opening mold wall not clean (3) insufficient gas supply of compressed air or gas leakage

(1) increasing the temperature (2) clean the mouth mould  (3) Increase gas supply or check for air leakage and repair

Wall thickness uneven

(1) core mould and mould positioning is not straight (2)plasticizing uneven (3) traction is not normal (4) the compressed air is not stable (5) the nose temperature instability

(1)The center position of core die and mouth die should be adjusted (2) check traction device (3) The gas supply system should be stable (4) strengthen the plasticizing system of the control (5) check the nose heating equipment are in good condition, and make the nose surrounding temperature stability

On the surface of black lines

(1) The raw material additives are not evenly distributed(2) The raw materials are too illiquid(3) head parts and filters is too hot (4) the nose filter and shunt structure net is bad (5) The filter is not cleaned

(1) improve the mixing, stirring improve dispersion performance

(2)strengthened material  formula (3) decrease the temperature (4) check the filter and shunt (5) clean the filter

Surface wrinkles and ripples

(1) mouth mold temperature too high or uneven heating ‚ device (2) after heating water supply shortage, the water temperature is higher

(3) traction uneven mold discharging port too slow (4) mouth mold discharge is  not uniform 

(1) check whether the heating device is damaged, reduce the temperature  (2) increase water supply (3) appropriate  traction speed (4) adjust the mouth mould gap

The lining cracks

(1)Raw materials mixed with impurities (2) low mold temperature core (3) low temperature of cylinder (4) traction too fast (5) too much lubricant

(1) feed stock pretreatment (2)improve core mold temperature  (3) Raise cylinder temperature(4) slow traction speed (5) adjust the formula