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A turboexpander, particularly suited for use in a cryogenic rectification system, comprises a center housing rotatably supporting an elongated shaft to opposite ends of which are mounted a turbine wheel within a turbine housing and a compressor wheel within a compressor housing or a brake within a l

A turboexpander, particularly suited for use in a cryogenic rectification system, comprises a center housing rotatably supporting an elongated shaft to opposite ends of which are mounted a turbine wheel within a turbine housing and a compressor wheel within a compressor housing or a brake within a load housing. The turbine wheel has circumferentially spaced turbine blades. Process fluid is introduced so as to flow through annular nozzles or guide vanes which encompass the turbine wheel. The guide vanes direct the process fluid through the turbine blades and each extends between a leading edge more distant from the turbine wheel and a trailing edge less distant from the turbine wheel. Each guide vane is substantially uncontoured between its leading edge and the trailing edge and is substantially thicker at the leading edge than at the trailing edge. A thermal shield thermally isolates the turbine housing and the process fluid within the turbine housing from the central housing and the lubricant within said central housing. A labyrinth seal construction along the length of the shaft between the bearings and the turbine housing prevents migration of the lubricant along the shaft into the turbine housing and prevents migration of the process fluid out of the turbine housing along the shaft and into the central housing. Sealing gas may also be provided to the labyrinth seal construction as an additional expedient to prevent migration of the lubricant along the shaft and of the process fluid out of the turbine. Superior performance is achieved by the relative dimensioning of certain components.

대표청구항 ▼

A turboexpander capable of producing refrigeration, comprising: a center housing extending between first and second ends; a turbine housing attached to said first end of said center housing; a shaft having a longitudinal axis mounted on said center housing for rotation about said longitudinal axis,

A turboexpander capable of producing refrigeration, comprising: a center housing extending between first and second ends; a turbine housing attached to said first end of said center housing; a shaft having a longitudinal axis mounted on said center housing for rotation about said longitudinal axis, said shaft having a first end extending into said turbine housing and a second end supporting a load; a turbine wheel having an outer periphery mounted on said first end of said shaft and within said turbine housing for rotation with said shaft, said turbine wheel having a plurality of circumferentially spaced turbine blades thereon, each of said turbine blades extending between locations proximate said outer periphery of said turbine wheel and locations proximate said longitudinal axis; said turbine housing defining inlet means for receiving process fluid at a region distant from said longitudinal axis and for discharging the process fluid toward said turbine blades; and annular nozzle means intermediate said inlet means and said turbine wheel and encompassing said turbine wheel for directing the process fluid from said inlet means toward and through said turbine blades, said nozzle means including a plurality of guide vanes, each of said guide vanes extending between a leading edge more distant from said turbine wheel and a trailing edge less distant from said turbine wheel, the maximum distance between said trailing edges of said guide vanes and said outer periphery of said turbine wheel being in the range of approximately 1% to 4% of the turbine wheel radius.