Strut cover, exhaust casing, and gas turbine

Patent metadata

Field	Value
Publication number	US-2022325635-A1
Application number	US-202017634052-A
Country	US
Kind code	A1
Filing date	Sep 9, 2020
Priority date	Sep 12, 2019
Publication date	Oct 13, 2022
Grant date	—

Abstract

A strut cover for a gas turbine includes: a cylindrical sheet metal member having a hollow portion; and a flare member that is connected to one end of the cylindrical sheet metal member in an axial direction of the cylindrical sheet metal member and includes a curved portion having an outer surface such that a distance from a center axis of the cylindrical sheet metal member to the outer surface increases with increasing a distance from the cylindrical sheet metal member in the axial direction. The flare member has a thickness larger than a minimum thickness of the cylindrical sheet metal member at least in the curved portion.

First claim

1 . A strut cover for a gas turbine, comprising:
a cylindrical sheet metal member having a hollow portion; and a flare member that is connected to one end of the cylindrical sheet metal member in an axial direction of the cylindrical sheet metal member and includes a curved portion having an outer surface such that a distance from a center axis of the cylindrical sheet metal member to the outer surface increases with increasing a distance from the cylindrical sheet metal member in the axial direction, wherein the flare member has a thickness larger than a minimum thickness of the cylindrical sheet metal member at least in the curved portion.

2 . The strut cover according to claim 1 ,
wherein an inner surface of the curved portion of the flare member protrudes toward the center axis with respect to an inner surface of the cylindrical sheet metal member.

3 . The strut cover according to claim 1 ,
wherein the flare member includes:
a connection end connected to the cylindrical sheet metal member; and
a flange portion disposed on an opposite side of the curved portion from the connection end, and
wherein, in a cross-section along the center axis, the flare member bulges on an opposite side of a tangential line to an inner surface of the flange portion in an outer peripheral region of the flange portion from the cylindrical sheet metal member.

4 . The strut cover according to claim 3 ,
wherein, in a cross-section along the center axis, an inner surface of the bulge portion of the flare member that bulges on the opposite side of the tangential line from the cylindrical sheet metal member curves convexly.

5 . The strut cover according to claim 1 ,
wherein the flare member includes:
a connection end connected to the cylindrical sheet metal member; and
a flange portion disposed on an opposite side of the curved portion from the connection end, and
wherein the flare member includes:
a first region where a tangential direction to an outer surface of the flange portion and the center axis makes a first angle; and
a second region, disposed so as to face the first region with the center axis therebetween, where the tangential direction to the outer surface of the flange portion and the center axis makes a second angle that is larger than the first angle, wherein the curved portion has a smaller thickness in the second region than in the first region.

6 . The strut cover according to claim 5 ,
wherein, in a cross-section perpendicular to the center axis, the hollow portion has a minor axis and a major axis larger than the minor axis, and wherein the first region and the second region of the flare member face each other in a direction along the major axis of the hollow portion, with the center axis therebetween.

7 . The strut cover according to claim 5 ,
wherein, in a cross-section perpendicular to the center axis, the hollow portion has a minor axis and a major axis larger than the minor axis, and wherein the first region and the second region of the flare member face each other in a direction along the minor axis of the hollow portion, with the center axis therebetween.

8 . The strut cover according to claim 1 ,
wherein the flare member includes:
a connection end connected to the cylindrical sheet metal member; and
a cylindrical portion extending along the center axis between the curved portion and the connection end,
wherein, in a cross-section perpendicular to the center axis, the hollow portion has a minor axis and a major axis larger than the minor axis, and wherein the flare member includes:
a third region intersecting a straight line extending from the center axis in a direction along the major axis in a cross-section perpendicular to the center axis; and
a fourth region intersecting a straight line extending from the center axis in a direction along the minor axis in a cross-section perpendicular to the center axis, wherein the cylindrical portion has a thinner thickness in the fourth region than in the third region.

9 . The strut cover according to claim 1 ,
wherein the flare member is a casting part formed by casting.

10 . An exhaust casing of a gas turbine, comprising:
a cylindrical casing wall; a cylindrical outer diffuser disposed on a radially inner side of the casing wall; an inner diffuser disposed on a radially inner side of the outer diffuser and forming a diffuser passage between the inner diffuser and the outer diffuser; and the strut cover according to claim 1 , wherein the flare member of the strut cover includes:
an outer flare member connected to the outer diffuser; and
an inner flare member connected to the inner diffuser.

11 . The exhaust casing according to claim 10 ,
wherein, in a cross-section along an axis of the exhaust casing, a thickness of the curved portion upstream of at least the center axis in the diffuser passage is thicker in the outer flare member than in the inner flare member.

12 . The exhaust casing according to claim 10 ,
wherein at least one of the outer diffuser or the inner diffuser is a sheet metal part.

13 . A gas turbine, comprising the exhaust casing according to claim 10 .

Assignees

• Mitsubishi Heavy Ind Ltd

Inventors

• Hirata Tomoyuki
• Tsutsumi Eiichi
• Kitagawa Kazuki
• Iijima Takayoshi

Classifications

• F05D2220/32

  in gas turbines · CPC title

• F02C7/20

  Mounting or supporting of plant; Accommodating heat expansion or creep · CPC title

• F01D25/30 Primary

  Exhaust heads, chambers, or the like · CPC title

• F01D25/28

  Supporting or mounting arrangements, e.g. for turbine casing · CPC title

• F05D2230/21

  by casting · CPC title