| abstract |
A screw machine ( 10 ) has a rotor housing ( 12 ) defining overlapping bores ( 12 - 1, 12 - 2 ). Female rotor ( 14 ) is located in bore ( 12 - 1 ) and male rotor ( 16 ) is located in bore ( 12 - 2 ). A wear resistant coating is deposited on the tips ( 14 - 1, 16 - 1 ) of the rotors. A conformable coating is deposited on the valleys ( 14 - 2, 16 - 2 ) of the rotors. A conformable coating is deposited on the surface of the bores coacting with the rotors. |