POWER RECOVERY MACHINE

摘要

A machine for recovering power from a flow of compressed gas, for example, natural gas comprises, firstly, a turbo-expander 2 having a turbo-expander wheel 6 and, secondly, a generator 4 having a rotor 10 able to be driven by the turbo-expander wheel 6 and a stator 12 about the rotor 10. The turbo- expander 2 and the generator 4 are housed in a length of pipe 14. The turbo- expander wheel 6 has an obverse side 7 facing the generator 4. There is a flow passage 42 for the flow of expanded gas that places the obverse side 7 of the wheel 6 in gas flow communication with the outer surface of the stator 12. This outer surface typically carries fins 44 to facilitate cooling of the stator 12 by expanded gas from the turbo-expander 2.