A method, HVACR system, and positive displacement compressor that includes a compressor housing and a rotating component and at least one second component. Each of the rotating component and the at least one second component have a contacting surface that define a meshing location between the rotating component and the at least one second component to form a compression chamber. Additionally, a coating layer is provided on the contacting surface of at least one of the rotating component or the at least one second component, in which the coating layer includes at least a first applied layer and a second applied layer. The first layer and the second layer are separate layers and both the first layer and the second layer include a conforming material, in which the conforming material in the first applied layer has a different particle size than the conforming material in the second applied layer.

A blower assembly includes, but is not limited to, a blower housing defining a blower chamber and including a gas inlet and a gas outlet; a first rotor positioned within the blower chamber and adapted for rotation therein, the first rotor including a first shaft and at least two lobes defining a first lobe profile; and a second rotor positioned within the blower chamber and adapted for rotation therein, the second rotor including a second shaft and at least two lobes defining a second lobe profile, wherein the first and second rotors are formed from a metal having a coefficient of thermal expansion from about 1 (10.sup.6 in/in*K) to about 13 (10.sup.6 in/in*K), and wherein at least one of the outer surface of the first rotor, the outer surface of the second rotor, or the blower chamber includes a coating.

The disclosure relates to a screw pump comprising: a casing with an inlet, an outlet and a flow chamber between the inlet and the outlet; and at least two screws housed in the flow chamber to force a fluid flow through the flow chamber from the inlet to the outlet; wherein at least one of the screws comprises a lubricated polymer material.

The disclosure relates to a screw pump comprising: a casing with an inlet, an outlet and a flow chamber between the inlet and the outlet; and at least two screws housed in the flow chamber to force a fluid flow through the flow chamber from the inlet to the outlet; wherein at least one of the screws comprises a lubricated polymer material.