Abstract: A rotary compression equipment includes: a housing having at least two intermeshing hollow rotors rotatably mounted in the housing by two shafts, each rotor formed with a hollow portion for passing a coolant in the hollow portion for cooling the meshing rotors when rotated, and a coolant passage formed in each shaft and fluidically communicated with the hollow portion in the rotor for leading coolant from the coolant passage into the hollow portion in the rotor for removing heat of the rotors outwardly for reducing thermal expansion of the rotary equipment and increasing the efficiency of the rotary equipment.

Abstract: A screw compressor or pump includes: a housing, two intermeshing rotors respectively rotatably mounted in the housing by two shafts; each rotor having a helix tooth spirally formed on the rotor lengthwise, with the helix tooth gradually decreasing an outer diameter of a top land surface of the helix tooth corresponding to a gradually contracted rotor chamber, and having a spiral groove juxtapositioned to the helix tooth and spirally formed in the rotor lengthwise; the spiral groove having a groove bottom surface extrapolatively defining an inner cone tapered towards a suction port side; the rotor chamber having a conical wall surface extrapolatively defining an outer cone tapered towards a discharge port side, thereby forming a gradationally contracted cavity between the spiral groove and the conical wall surface of the rotor chamber as confined between the inner and outer cones for increasing the compression or pumping efficiency.