Tips for daily maintenance of bimetallic screws


Reasons for screw wear caused by bimetallic screw and m […]

Reasons for screw wear caused by bimetallic screw and methods to reduce wear
1. Each plastic raw material has an ideal plasticizing processing temperature range, so the processing temperature of the barrel should be controlled to make it close to this temperature range. Granular plastic enters the barrel from the hopper and first reaches the feeding section. Dry friction will inevitably occur in the feeding section. When these plastics are not heated enough and melted unevenly, it is easy to cause increased wear on the inner wall of the barrel and the surface of the screw; In the compression section and the homogenization section, if the molten state of the plastic is disordered and uneven, it will also cause increased wear.
2. The speed should be adjusted properly. Because some plastics are added with strengthening agents, such as glass fiber, minerals or other fillers. The friction of these substances on metal materials is often much greater than that of molten plastics. When injecting these plastics, if a high speed is used, then while increasing the shearing force on the plastic, it will also cause the reinforcement to produce more shredded fibers. The shredded fibers contain sharp ends, which will cause wear. The strength is greatly increased. When inorganic minerals slide at high speed on the metal surface, their scraping effect is not small.

Types of bimetallic screws: gradient type, mutation type, wave type, barrier type, double screen type, cone type, split type, separate type, exhaust type, pin type, hybrid type, double head, three head, multi head, granulation Type and so on.

Daily maintenance of bimetallic screw
1. Do not start the machine when the barrel screw has not reached the preset temperature.
2. Prevent metal fragments and debris from falling into the hopper. If processing recycled materials, a magnetic hopper must be added to prevent iron filings from entering the hopper.
3. When using anti-salivation, make sure that the plastic in the barrel is completely melted, so as not to damage the transmission system parts when the screw is retracted.
4. When using new plastic, the remaining material in the barrel should be cleaned.
5. When the temperature of the molten plastic is normal but black spots or discoloration of the molten plastic are constantly found, the rubber screw should be checked.
6. During processing, try to make the material evenly plasticized, don't let metal foreign matter mix into the material, and reduce the rotating torque of the screw barrel.


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