Method for cleaning PVC extruder by using rubber

Abstract

The invention discloses a method for cleaning a PVC extruder by using rubber. The method comprises the following steps of: after processing of an extruded product is finished and before an extruder is cleaned, detaching a machine head, and cleaning up residual PVC in the machine head; regulating the temperature of each section of the extruder to reach the needed lowest extrusion temperature required by fusing PVC, and discharging the residual PVC in a cylinder, slowly adding rubber into the cylinder when only a little PVC is extruded at a die, reducing the temperature of each section of the extruder to softening temperature of the rubber, and reducing the screw speed until a great amount of mixture of rubber and PVC can be seen at the die of the extruder; continuously adding the rubber, stopping feeding when PVC is hardly mixed in the rubber, properly raising the temperature of each section of the extruder and improving the screw speed to 80 to 100 revolutions per minute, and stoppingheating each section of the extruder cylinder until no rubber is extruded, and stopping rotating the screw; and finally separating PVC residues and rubber and finishing cleaning.

Description

technical field [0001] The invention relates to a cleaning method for an extruder, in particular to a method for cleaning a PVC extruder with rubber. Background technique [0002] The main component of PVC is polyvinyl chloride polyhydroethylene, which has bright color, corrosion resistance, firmness and durability. Due to the addition of some toxic auxiliary materials such as plasticizers and anti-aging agents in the manufacturing process to enhance its heat resistance, toughness and ductility Therefore, its products generally do not store food and medicine. It is a well-loved, popular and widely used synthetic material in the world today. It has the advantages of good processing performance, low manufacturing cost, corrosion resistance, and insulation. Its global usage is the second highest among all synthetic materials. However, PVC has poor thermal stability and light resistance. It can start to decompose and release hydrogen chloride (HCl) gas at above 140 °C, which p...

AI Technical Summary

Problems solved by technology

[0009] 4. Use a special extruder cleaning agent to clean the barrel and screw. Although this method has a better cleaning effect and is convenient and quick, the price of the cleaning agent is very high, so for extruders that require frequent refueling for processing In terms of cost, it is not advisable

Solid screw cleaning agent is a product specially used for cleaning the screw and barrel of injection molding, extrusion molding and blow molding machines. It is an excellent helper for screw and barrel color change, refueling and preventive machine maintenance. Solid screw cleaning agents have certain limitations in terms of cleaning efficiency, environmental protection, and cost. For example, more environmentally friendly resin cleaning agents are difficult to clean to the dead corners and gaps of the screw barrel, and the cleaning efficiency is low; while adding organic solvents Although the screw cleaning agent improves the cleaning efficiency, it has the problem of environmental pollution; those screw cleaning agents that add abrasives also cause wear on the corresponding mechanical surface while cleaning the screw barrel. There are almost no efficient and environmentally friendly products in China. Solid screw cleaning agent products, high-efficiency solid screw cleaning agents commonly used in the industry mainly rely on imports