Screw compressor with multi-layered coating of the rotor screws

A method for applying a multilayer coating to surfaces of a rotor screw of a screw compressor, the method comprising:

• applying a first layer of a first thermoplastic synthetic material to a profiled surface of the rotor screw, the rotor screw comprising a single-part or multi-part base body with two end faces and the profiled surface extending therebetween and shaft ends projecting beyond the end faces, each of the shaft ends comprising a bearing seat and seal seats between the bearing seat and the end face;
• coating the first layer of synthetic material on the profile surface with a second layer of a second thermoplastic synthetic material;
• applying only the first layer of the first thermoplastic synthetic material to each of the seal seats of the rotor screw;
• wherein particles or pores supporting a running-in process are embedded in the second layer and the second thermoplastic synthetic material defines a matrix for receiving the particles or for forming the pores, respectively.

A screw compressor comprising:

• a compressor housing;
• two rotor screws mounted axially parallel in the compressor housing, the two rotor screws meshing with each other in a compression space and synchronized with each other in their rotational movement;
• and
• a drive in communication with the two rotor screws to rotate the rotor screws;
• wherein:
• each profiled surface is coated with a first layer and the first layer is coated with a second layer, wherein the first layer and the second layer both comprise a thermoplastic synthetic material;
• and
• each of shaft ends comprising a bearing seat, each of the bearing seats is uncoated;
• wherein particles or pores supporting a running-in process are embedded in the second layer and the thermoplastic synthetic material defines a matrix for receiving the particles or for forming the pores, respectively.

A method for applying a multilayer coating to surfaces of a rotor screw of a screw compressor, the method comprising:

• applying a first layer of a first thermoplastic synthetic material to a profiled surface of the rotor screw, the rotor screw comprising a single-part or multi-part base body with two end faces and the profiled surface extending therebetween and shaft ends projecting beyond the end faces, each of the shaft ends comprising a bearing seat and seal seats between the bearing seat and the end face;
• coating the first layer of synthetic material on the profile surface with a second layer of a second thermoplastic synthetic material;
• and
• maintaining each of the bearing seats uncoated by either the first layer or the second layer;
• wherein particles or pores supporting a running-in process are embedded in the second layer and the second thermoplastic synthetic material defines a matrix for receiving the particles or for forming the pores, respectively.