Shielding pockets for case holes

Patent metadata

Field	Value
Publication number	US-2016201511-A1
Application number	US-201414913621-A
Country	US
Kind code	A1
Filing date	Sep 12, 2014
Priority date	Sep 13, 2013
Publication date	Jul 14, 2016
Grant date	—

Abstract

A case is provided for a gas turbine engine. The case includes a wall defining a through-hole. The case also includes first and second pockets adjacent to, and on opposite sides, of the through hole. A method of reducing stress in a case of a gas turbine engine is also provided that includes reducing stress about a through-hole by providing a concavity on each side of the through-hole.

First claim

What is claimed is:

1 . A case for a gas turbine engine, the case comprising:
a wall defining a through-hole; and first and second pockets adjacent to, and on opposite sides, of the through hole.

2 . The case as recited in claim 1 , wherein at least one of the first or the second pockets each includes a circular periphery.

3 . The case as recited in claim 1 , wherein at least one of the first or the second pockets each includes a race track shaped periphery.

4 . The case as recited in claim 1 , wherein at least one of the first or the second pockets each includes a rectilinear shaped periphery.

5 . The case as recited in claim 1 , wherein the first and the second pockets circumferentially flank the through-hole.

6 . The case as recited in claim 1 , wherein at least one of the first or the second pockets each extends a depth from the inner surface of between 10%-50% of a thickness of the wall.

7 . The case as recited in claim 1 , wherein at least one of the first or the second pocket is 100%-500% a diameter of the through-hole.

8 . The case as recited in claim 1 , wherein an outer periphery of at least one of the first or the second pockets is circumferentially spaced a distance from an outer diameter of the through-hole along a hoop line, and the distance is between 10%-100% the diameter of the through-hole.

9 . The case as recited in claim 1 , wherein
at least one pocket extends for a depth from the inner surface between 10%-50% a thickness of the wall and has a diameter of 100%-500% of a diameter of the through-hole; and the pocket has an outer edge circumferentially spaced a distance from a surface defining the through-hole along a hoop line, and the distance is between 10%-100% of the diameter of the through-hole.

10 . The case as recited in claim 1 , wherein the wall is an outer wall of a diffuser case.

11 . The case as recited in claim 1 , wherein the through-hole is located through a boss.

12 . A method of reducing stress in a case of a gas turbine engine, comprising:
reducing stress about a through-hole by providing a concavity on each side of the through-hole.

13 . The method as recited in claim 12 , further comprising defining each pocket in an inner surface of a wall.

14 . The method as recited in claim 13 , further comprising defining each pocket for a depth from an inner surface of the case between 10%-50% of a thickness of the wall.

15 . The method as recited in claim 13 , further comprising defining each pocket with an outer edge having a diameter of between 100%-500% of a diameter of the through-hole.

16 . The method as recited in claim 13 , further comprising circumferentially spacing each pocket a distance along a hoop line from between 10%-400% of a diameter of the through-hole.

Assignees

• United Technologies Corp
• Mitsubishi Heavy Ind America Inc

Inventors

• Chang Jr Hoyt Y
• Ichihashi Yusuke
• Fujimoto Yohei
• Dale Timothy

Classifications

• F05D2250/20

  Three-dimensional · CPC title

• F23R3/002

  Wall structures (F23R3/02 and F23R3/007 take precedence) · CPC title

• F01D25/24 Primary

  Casings (modified for heating or cooling F01D25/14); Casing parts, e.g. diaphragms, casing fastenings (casings for rotary machines or engines in general F16M {; special arrangements in stators dealing with breaking-off of part of rotor F01D21/045}) · CPC title

• F05D2260/941

  particularly aimed at mechanical or thermal stress reduction · CPC title

• F05D2250/713

  inflexed · CPC title