Screw is an important part of injection molding machine. Its role is to transport, compact, melt, stir and apply pressure to the plastic. All this is done by the rotation of the screw in the barrel. When the screw rotates, plastic will cause friction and mutual movement between the inner wall of the barrel, the bottom surface of the screw groove of the screw, the advance surface of the screw edge, and plastic and plastic.
Reasons for screw damage of high quality injection molding machine alloy screw manufacturers
1. The temperature is low when the raw materials are plasticized;
2. Metal foreign materials are mixed in the raw materials or there are many impurities in the raw materials;
3. The screw idle running time is too long;
4. Unreasonable choice of materials for manufacturing screw;
5. Low screw manufacturing accuracy and low heat treatment hardness of thread working surface.
Features of high-quality injection molding machine alloy screw manufacturers :
1.Abrasion resistance and long life;
2. High temperature resistance, no deformation under high temperature;
3. Corrosion resistance, the material is corrosive;
4. Good cutting performance;
5, high strength, can withstand large torque, high speed;
6. Low residual stress and small thermal deformation after heat treatment;
The materials commonly used to produce screws are:
6.Tungsten carbide alloy, tungsten carbide nickel-based alloy
7.Full hardened powder alloy (full alloy)
8.High temperature alloy
Overcooling of the barrel end is one of the main causes of screw slippage. The barrel of the injection machine is divided into 3 sections. At the end, that is, the feeding section, the pellets will form a layer of melt film and stick to the screw during the heating and compression process. Without this film, the pellets cannot be easily transported to the front end.
The material in the feed section must be heated to a critical temperature to form that critical melt film. However, the residence time of the material in the feeding section is usually short and cannot reach the required temperature. This situation usually occurs on small injection machines. Too short residence time will cause incomplete melting and mixing of the polymer, which will cause the screw to slip or stall.
Tips: In order to avoid purchasing risks, it is recommended that you confirm the supplier's qualification and product quality before purchasing the product.