Geothermal turbine

Patent metadata

Field	Value
Publication number	US-10935007-B2
Application number	US-201716475909-A
Country	US
Kind code	B2
Filing date	Dec 19, 2017
Priority date	Feb 10, 2017
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

A geothermal turbine includes: a rotor; a casing which houses the rotor; a plurality of rotor blades disposed around the rotor; a plurality of stationary vanes supported on the casing; at least one seal portion disposed in a gap between the rotor and the casing at an upstream side of a first-stage rotor blade of the plurality of rotor blades so as to seal leakage steam which flows out inward in a radial direction of the rotor from between a first-stage stationary vane of the plurality of stationary vanes and the first-stage rotor blade; and a steam passage configured to extract a part of steam after passing the first-stage stationary vane and discharge the part of steam to the gap through an interior of the first-stage stationary vane.

First claim

The invention claimed is:

1. A geothermal turbine, comprising:
a rotor;
a casing which houses the rotor;
a plurality of rotor blades disposed around the rotor;
a plurality of stationary vanes supported on the casing;
at least one seal portion disposed in a gap between the rotor and the casing at an upstream side of a first-stage rotor blade of the plurality of rotor blades so as to seal leakage steam which flows out inward in a radial direction of the rotor from between a first-stage stationary vane of the plurality of stationary vanes and the first-stage rotor blade; and
a steam passage configured to extract a part of steam after passing the first-stage stationary vane and discharge the part of steam to the gap through an interior of the first-stage stationary vane,
wherein each of the plurality of stationary vanes includes a vane body portion and an inner race positioned at an inner side of the vane body portion in the radial direction, and
wherein the steam passage has a steam outlet disposed on a boundary between the casing and the inner race of the first-stage stationary vane.

2. The geothermal turbine according to claim 1 ,
wherein the steam passage has a steam outlet disposed at a downstream side of at least one of the at least one seal portion with respect to a flow of the leakage steam.

3. The geothermal turbine according to claim 2 ,
wherein the at least one seal portion includes an inner race seal portion disposed between the rotor and the inner race of the first-stage stationary vane, and
wherein the steam passage has a steam outlet disposed at a downstream side of the inner race seal portion with respect to the flow of the leakage steam.

4. A geothermal turbine, comprising:
a rotor;
a casing which houses the rotor;
a plurality of rotor blades disposed around the rotor;
a plurality of stationary vanes supported on the casing;
at least one seal portion disposed in a gap between the rotor and the casing at an upstream side of a first-stage rotor blade of the plurality of rotor blades so as to seal leakage steam which flows out inward in a radial direction of the rotor from between a first-stage stationary vane of the plurality of stationary vanes and the first-stage rotor blade; and
a steam passage configured to extract a part of steam after passing the first-stage stationary vane and discharge the part of steam to the gap through an interior of the first-stage stationary vane,
wherein each of the plurality of stationary vanes includes a vane body portion and an inner race positioned at an inner side of the vane body portion in the radial direction,
wherein the at least one seal portion includes an inner race seal portion disposed between the rotor and the inner race of the first-stage stationary vane,
wherein the inner race seal portion includes a rotor facing surface which faces the rotor, an upstream surface positioned at an upstream side of the rotor facing surface with respect to a flow direction of the leakage steam, and a downstream surface positioned at a downstream side of the rotor facing surface with respect to a flow of the leakage steam, and
wherein the steam passage has a steam outlet disposed on the downstream surface.

5. The geothermal turbine according to claim 1 ,
wherein each of the plurality of stationary vanes includes a vane body portion, an inner race positioned at an inner side of the vane body portion in the radial direction, and an outer race positioned at an outer side of the vane body portion in the radial direction, and
wherein at least one of the inner race of the first-stage stationary vane or the outer race of the first-stage stationary vane has an annular hollow section inside thereof.

Assignees

• Mitsubishi Hitachi Power Sys
• Mitsubishi Power Ltd

Inventors

• TAKATA Ryo
• Tsuchiya Mitsuyoshi
• Shibata Yu

Classifications

• F01K21/00

  Steam engine plants not otherwise provided for · CPC title

• F01D1/02

  with stationary working-fluid guiding means and bladed or like rotor, {e.g. multi-bladed impulse steam turbines}(F01D1/24 takes precedence; without stationary working-fluid guiding means F01D1/18) · CPC title

• F16J15/447

  Labyrinth packings · CPC title

• F01D9/065

  Fluid supply or removal conduits traversing the working fluid flow, e.g. for lubrication-, cooling-, or sealing fluids (see also F01D25/16, F01D25/24 and F01D25/26) · CPC title

• F02C7/125

  by partial arc admission of the working fluid or by intermittent admission of working and cooling fluid · CPC title