SCREW EXPANSION MACHINE Russian patent published in 2008 - IPC F01C1/16 

FIELD: mechanical engineering; drives.

SUBSTANCE: invention relates to design of screw expansion machines operating on steam or natural gas for use as drives for electric generators. Proposed screw expansion machine has high-pressure housing with intake branch pipe to deliver high-pressure gas and low-pressure housing with discharge branch pipe to discharge waste low-pressure gas, driving and driven rotors installed in bearings arranged in pairs in high-pressure and low-pressure housing, rotors being intercoupled by means of synchronizing gears and provided, in middle part, with teeth in meshing. High-pressure and low-pressure housings are connected in division plane passing along high-pressure end faces of helical teeth square to rotor axes. Driving and driven rotors are furnished with relief pistons found in high-pressure housing. End faces of pistons pointed to helical teeth communicate with intake branch pipe. Bottom with holes for shafts of rotors, intake port and two coaxial centering belts located on perimeter of bottom is arranged in division plane of high-pressure and low-pressure housing. One belt is mated with high-pressure housing, and the other, with low-pressure housing.

EFFECT: increased service life of screw machine owing to reduction of axial forces acting onto rotors, improved manufacturability and repairability of machine.

2 cl, 2 dwg