Qingdao Trusty Plastic Machinery Co.,Ltd.

Acetylene flame should not be used to remove residual plastic from plastic extruder screw

Release time:2022-10-28 13:00

When we use extruder equipment for plastic extrusion molding production, sometimes plastic products manufacturers need to replace the screw of the extruder, and a large amount of plastic is stuck on the replaced screw. If we do not clean the screw, it is not conducive to the maintenance and preservation of the screw, and it is not convenient for the next use.

In order to do a good job of cleaning the screw, the most common and fastest cleaning method is to remove the plastic of the screw by burning or roasting. As we all know, acetylene flame is a common flame mode, but we cannot use acetylene flame to clean the residual plastic on the screw of the plastic extruder. The main reason is that the temperature of acetylene flame can reach 3000 ℃, and cleaning with this high-temperature flame will damage the metal properties of the screw and affect the mechanical tolerance of the screw. For example, when acetylene flame bakes a part of the screw, the flame turns into a lasting blue, which means that the metal structure of this part of the screw has changed, which will reduce the wear resistance of this part, and even peel off the wear-resistant layer from the base metal. In addition, the local heating of the acetylene flame will also cause overheating of one side of the screw, which will cause the screw to bend. Most screws are made of 4140. H.T. steel with very tight tolerances, generally within 0.03mm. The straightness of the screw is mostly within 0.01mm. When the screw is baked and cooled by the acetylene flame, it is usually difficult to return to the original straightness.

Therefore, we generally recommend using the flame of the blowtorch to clean up the residual plastic on the extruder screw. I hope the above information can give you corresponding help.