Ring segment of gas turbine

• US 20040047725A1
• Filed: 09/06/2002
• Published: 03/11/2004
• Est. Priority Date: 09/06/2002
• Status: Active Grant

• Current Assignee: Mitsubishi Heavy Industries, Ltd.
• Original Assignee: Mitsubishi Heavy Industries, Ltd.
• Inventors: Inoue, Shinichi, Isumi, Osamu, Matsuoka, Hiroshige, Laurello, Vincent, Soechting, Friedrich, Tomita, Yasuoki
• Granted Patent: US 7,033,138 B2
• Time in Patent Office: Days
• US Class Current: 415/116
• CPC Class Codes: F01D 11/005 Sealing means between non relatively rotating elements
• CPC Class Codes: F01D 11/08 for sealing space between rotor blade tips and stator specially-shaped blade tips therefor F01D5/20
• CPC Class Codes: F01D 25/12 Cooling
• CPC Class Codes: F01D 25/246 Fastening of diaphragms or stator-rings
• CPC Class Codes: F05D 2240/55 Seals
• CPC Class Codes: F05D 2260/201 by impingement of a fluid

Abstract

An object of the present invention is to provide a ring segment of a gas turbine in which the temperature is maintained low, damage due to high temperature oxidization is prevented, and high temperature deformation is prevented. In order to achieve the object, the present invention provides a ring segment of a gas turbine which comprises a blade ring, a main shaft and moving blades comprising a plurality of individual units which define an annular form by being arranged around the peripheral direction of the main shaft, and disposed so that its inner peripheral surface is maintained at a constant distance from the tips of the moving blades, wherein grooves which extends along the axial direction of the main shaft of the turbine are formed upon of the individual units so as mutually to confront one another; a seal plate which is inserted into each mutually confronting pair of the grooves so as to connect together the adjacent pair of individual units; and contact surfaces which are formed at positions more radially inward than the seal plates, which extend in the axial direction and the peripheral direction and which mutually contact one another.

Claims

1. A ring segment of a gas turbine which comprises a blade ring, a main shaft and moving blades, comprising a plurality of individual units which define an annular form by being arranged around the peripheral direction of the main shaft, and disposed so that its inner peripheral surface is maintained at a constant distance from the tips of the moving blades,

wherein the indivisual unit comprises grooves which extend along the axial direction of the main shaft, and each of which faces to a groove formed in the other indivisual unit;

a seal plate for connecting together the adjacent pair of individual units which is inserted into the groove; and

a contact surface which is formed at position more radially inward than the seal plate, which contacts another contact surface of the other indivisual unit in the axial direction and the peripheral direction of the main shaft.

8. A ring segment of a gas turbine as described in any one of claims 1, 2, and 4 to 7, wherein a gap between the individual units is greater than zero and less than or equal to 1 mm when the gas turbine is operating nominally.

9. A ring segment of a gas turbine as described in any one of claims 1, 2, and 4 to 7, wherein the thickness of the body of each of the individual units is greater than or equal to 1 mm and less than or equal to 4 mm.

10. A ring segment of a gas turbine as described in any one of claims 1, 2, and 4 to 7, wherein the individual unit comprises projections formed upon the outer peripheral surface thereof.

11. A ring segment of a gas turbine as described in any one of claims 1, 2, and 4 to 7, wherein the indivusual unit further comprises flanges for being fitted to the blade ring, and the flange comprises a plurality of slits which are formed so as to extend along the axial direction of the main shaft.

12. A ring segment of a gas turbine as described in any one of claims 1, 2, and 4 to 7, wherein the indivisual unit further comprises strengthening ribs which are provided upon the outer peripheral surface thereof.

13. A ring segment of a gas turbine as described in any one of claims 1, 2, and 4 to 7, wherein the indivisual unit is made from nickel alloy.

2. A ring segment of a gas turbine which comprises a blade ring, a main shaft and moving blades, comprising a plurality of individual units which define an annular form by being arranged around the peripheral direction of the main shaft, and disposed so that its inner peripheral surface is maintained at a constant distance from the tips of the moving blades,

wherein the individual units comprises ejection apertures for blowing out air to the adjacent individual units.

3. A ring segment of a gas turbine as described in claim 2, wherein the indivisual unit comprises ejection apertures which are upon each adjacent pair of the individual units at positions which alternate along the axial direction of the main shaft.

4. A ring segment of a gas turbine which comprises a blade ring, a main shaft and moving blades, comprising a plurality of individual units which define an annular form by being arranged around the peripheral direction of the main shaft, and disposed so that its inner peripheral surface is maintained at a constant distance from the tips of the moving blades,

wherein the individual unit comprises beveled portions between its side edges which face the adjacent ones of the individual units and its inner peripheral surface.

5. A ring segment of a gas turbine which comprises a blade ring, a main shaft and moving blades, comprising a plurality of individual units which define an annular form by being arranged around the peripheral direction of the main shaft, and disposed so that its inner peripheral surface is maintained at a constant distance from the tips of the moving blades,

wherein, the individual unit comprises:

first cooling conduits which are pierced from the outer peripheral surface to the end surface of the individual unit along the axial direction of the main shaft, and which cool the individual unit by supplying air from the outer peripheral surface; and

second cooling conduits which are pierced from the outer peripheral surface to the other end surface opposite the end surface in which the first cooling conduits, and which cool the individual unit by supplying air from the outer peripheral surface.

6. A ring segment of a gas turbine which comprises a blade ring, a main shaft and moving blades, comprising a plurality of individual units which define an annular form by being arranged around the peripheral direction of the main shaft, and disposed so that its inner peripheral surface is maintained at a constant distance from the tips of the moving blades,

wherein the individual unit comprises third cooling conduits which are pierced from the outer peripheral surface to the side edges which face the adjacent indivisual unit, and which cool the individual unit by supplying air from the outer peripheral surface.

7. A ring segment of a gas turbine which comprises a blade ring, a main shaft and moving blades, comprising a plurality of individual units which define an annular form by being arranged around the peripheral direction of the main shaft, and disposed so that its inner peripheral surface is maintained at a constant distance from the tips of the moving blades,

wherein the indivisual unit comprises least two of:

grooves which extend along the axial direction of the main shaft, and each of which faces to a groove formed in the other indivisual unit;

a seal plate for connecting together the adjacent pair of individual units which is inserted into the groove;

a contact surface which is formed at position more radially inward than the seal plate, which contacts another contact surface of the other indivisual unit in the axial direction and the peripheral direction of the main shaft;

ejection apertures for blowing out air to the adjacent individual units;

ejection apertures which are upon each adjacent pair of the individual units at positions which alternate along the axial direction of the main shaft;

beveled portions between its side edges which face the adjacent ones of the individual units and its inner peripheral surface;

first cooling conduits which are pierced from the outer peripheral surface to the end surface of the individual unit along the axial direction of the main shaft, and which cool the individual unit by supplying air from the outer peripheral surface;

second cooling conduits which are pierced from the outer peripheral surface to the other end surface opposite the end surface in which the first cooling conduits, and which cool the individual unit by supplying air from the outer peripheral surface; and

third cooling conduits which are pierced from the outer peripheral surface to the side edges which face the adjacent indivisual unit, and which cool the individual unit by supplying air from the outer peripheral surface.