Plastic pipe extrusion molding process parameters
Release time:
2022-07-28
Temperature is one of the important conditions for the smooth progress of extrusion molding. Starting from powdery or granular solid materials, high-temperature products are extruded from the head and undergo a complex temperature change process. Strictly speaking, the extrusion molding temperature should refer to the temperature of the plastic melt, but the temperature depends to a large extent on the temperature of the barrel and the screw, and a small part comes from the frictional heat generated when mixing in the barrel, so the barrel temperature is often used to approximate the molding temperature. Since the temperature of the barrel and the plastic is different in each section of the screw, in order to make the process of conveying, melting, homogenizing and extruding the plastic in the barrel smoothly, so as to produce high-quality parts, the key problem is to control the temperature of each section of the barrel, and the adjustment of the barrel temperature is realized by the heating and cooling system and the temperature control system of the extruder. The temperature of the head must be controlled below the thermal decomposition temperature of the plastic, and the temperature of the die can be slightly lower than the temperature of the head, but the plastic melt should be guaranteed to have good fluidity. In addition, the temperature fluctuation and temperature difference in the molding process will cause the plastic parts to produce residual stress, uneven strength of each point and the surface is gray and dull. There are many factors that produce this fluctuation and temperature difference, such as unstable heating and cooling systems, changes in screw speed, etc., but the quality of screw design and selection is affected.
Temperature is one of the important conditions for the smooth progress of extrusion molding. Starting from powdery or granular solid materials, high-temperature products are extruded from the head and undergo a complex temperature change process. Strictly speaking, the extrusion molding temperature should refer to the temperature of the plastic melt, but the temperature depends to a large extent on the temperature of the barrel and the screw, and a small part comes from the frictional heat generated when mixing in the barrel, so the barrel temperature is often used to approximate the molding temperature.
Since the temperature of the barrel and the plastic is different in each section of the screw, in order to make the process of conveying, melting, homogenizing and extruding the plastic in the barrel smoothly, so as to produce high-quality parts, the key problem is to control the temperature of each section of the barrel, and the adjustment of the barrel temperature is realized by the heating and cooling system and the temperature control system of the extruder.
The temperature of the head must be controlled below the thermal decomposition temperature of the plastic, and the temperature of the die can be slightly lower than the temperature of the head, but the plastic melt should be guaranteed to have good fluidity.
In addition, the temperature fluctuation and temperature difference in the molding process will cause the plastic parts to produce residual stress, uneven strength of each point and the surface is gray and dull. There are many factors that produce this fluctuation and temperature difference, such as unstable heating and cooling systems, changes in screw speed, etc., but the quality of screw design and selection is affected.
上一页： Study on Stabilizing Mechanism of Organotin Heat Stabilizer
Hot information
Company address: No.9 Guohua Road, Economic Development Zone, Guangde City, Anhui Province
Sales Hotline:0572-2216650
Service Hotline:0563-6988883
Company Website:http://www.xatchem.cn
Mobile website
Scan QR code