The coating problem of screw in exhaust plastic extrusion granulator
Hi
Granulator is used to make plastic granules which is used to plastic extrusion molding from exhaust plastics which are cut into slices first. Screw is core of granulator. Because of many hard particle in the exhaust plastics, such as stone, metal, screw undergo serious abrasive wear. The biggest of the abrasive have 5mm in length.
We have sprayed WC-CoCr on the surface of screw by JP8000.The quality of the coating is great. The part of screw was deformed in use because of pressure and the coating was peel off.
The hardness of screw in only HRC22, because it can be machininged easily. The hardness of the screw of maybe the reason of failure.
If arise the hardness, how much?
If you have other advice, please help me!
Thank you!
P.S. nitriding is used strengthen the screw but not enough. Cladding can only strengthen the top of screw.
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