1. Temperature control
Control of temperature is an important control factor in extrusion operations. The temperature of the control factors required for extrusion molding is the temperature of the barrel, the temperature of the diameter of the machine, and the temperature of the die.
If the temperature is too low, the plasticization is poor, the appearance of the hose is dull, the mechanical properties are poor, and the product quality cannot meet the requirements: if the temperature is too high, the material will decompose and the product will change color.
2. Screw speed
The screw speed increases and the extrusion volume increases, which can increase the output, but it is easy to produce poor plasticization, resulting in rough inner wall of the hose and a decrease in strength.
At this time, the head pressure should be adjusted to achieve better output and quality. The temperature control of the screw affects the material conveying rate, material plasticization, melting quality, etc.
Extruded hoses need to pass cooling water to reduce the temperature of the screw, which is conducive to improving the quality of plasticization. The temperature of the cooling water for the screw is about 50-70.
3. Traction speed
The adjustment of the traction speed is very important in the extrusion operation. After the material is extruded, melted and plasticized, it is continuously extruded from the die and then pulled into the setting device, cooling device, pulling device, etc.
The pulling speed should be consistent with the extrusion speed. match. Generally, in normal production, the traction speed should be about 1%-10% faster than the extrusion speed of the hose.
4. Compressed air and pressure
The compressed air can inflate the hose and the hose, so that the hose can maintain a certain roundness. The required pressure should be appropriate. If the pressure is too small, the hose will not be round, if the pressure is too large, the core mold will be cooled, the inner wall of the hose will be cracked and not smooth, and the quality of the hose will decrease.
At the same time, the pressure is required to be stable. If the pressure is suddenly large or small, the hose is prone to the status quo of bamboo knots.
5.Temperature of sizing device and cooling device.
Different sizing methods and cooling methods are used to extrude different plastic products. The cooling medium can be air, water or other liquids, and the temperature needs to be controlled. The temperature is mainly related to production efficiency and internal stress of the product.The above are the precautions for PVC hose production shared with you. I hope it will be helpful to you. If you need to know more about hoses, you are welcome to continue to pay attention to Orientflex.