PVC welding rod (2)
DATE：2022/11/17 8:32:25 / READ： / SOURCE：This station
PVC welding rod (2)
(3) Forming process① The plastic welding rod shall be extruded by using granulated materials to be put into the extruder for production. Refer to Chapter 4 for the mixing and extrusion granulation process conditions of raw materials for pelletizing.
② The temperature of each section of the extrusion welding rod barrel: 90~120 ℃ for the feeding section, 130~160 ℃ for the plasticizing section, and 160~180 ℃ for the homogenizing section.
③ Forming mold temperature: 170~190 ℃
If the extruder with medium screw diameter of 45mm is used, the working speed of the screw is about 20x/min.
① The electrode diameter is divided into 2mm, 2.5mm, 3mm, 3.5mm, 4mm and other specifications. The allowable diameter error is ± 0.3mm, and the length is not less than 500mm
② The color is generally gray or natural.
③ When the welding rod is bent for 180 ° at 15 ℃, it will not break.
④ The section of welding rod shall be tight, with uniform structure, and no air holes or impurities are allowed.
⑤ The surface of the welding rod shall be smooth and clean, free of bumps, bubbles and impurities.
① 80 mesh filter screen shall be added in front of the barrel when extruding shaped welding rods to ensure the quality of plastic welding rods.
② The surface of plastic welding rod is rough or has peeling phenomenon, which is mainly affected by the high temperature of molten material. The heating temperature of the barrel or the screw speed should be appropriately reduced.
③ If the surface of the plastic electrode is dark and lusterless or has white particles, it indicates that the raw materials are not plasticized evenly, and the heating temperature of the barrel should be appropriately increased.
④ The hollow phenomenon of products is generally affected by the high temperature of molten material, so the temperature of forming die should be appropriately reduced.
⑤ The product is not round, which is mainly affected by the high temperature of the die in the molding die. The die temperature should be reduced.
⑥ The cooling water tank shall be divided into two sections: the inlet section shall be cooled by hot water spraying, and the water temperature shall be 40~60 ℃; The second section is cooled by cooling water, and the products pass through the cooling water. Note: If the water temperature is too high or too low during cooling, it is easy to make the products hollow.
Author：admin