A screw expander is a positive displacement type equipment. It comprises of a meshing pair of helical lobed rotors contained in a casing which together form a working chamber, the volume of which depends only on the angle of rotation only on the angle of rotation. Other than a pair of screw rotor and the cylinder the structure consists of bearings, synchronous gears, seal assembly, etc.
The expander works by gas inflation and inner energy consumption. It has the inverse principle of the screw compressor, which has the similar basic structure and reversed working process.But its manufacturing process and control system is much more complex than the screw compressor.
