Containment casing

Patent metadata

Field	Value
Publication number	US-2016356286-A1
Application number	US-201615153339-A
Country	US
Kind code	A1
Filing date	May 12, 2016
Priority date	Jun 5, 2015
Publication date	Dec 8, 2016
Grant date	—

Abstract

The present invention provides a gas turbine engine comprising a tubular containment casing surrounding a rotary fan blade assembly. The radially outer perimeter (and optionally the radially inner perimeter) of the radial cross-sectional profile of the containment casing is non-circular e.g. polygonal, corrugated, fluted or wavy.

First claim

1 . A gas turbine engine comprising a tubular containment casing surrounding a rotary fan blade assembly, wherein the radially outer perimeter of the radial cross-sectional profile of the containment casing is non-circular.

2 . A gas turbine engine according to claim 1 wherein a radially inner perimeter of the radial cross-sectional profile of the containment casing is non-circular.

3 . A gas turbine engine according to claim 1 wherein the radially outer perimeter and/or the radially inner perimeter is polygonal, corrugated, fluted or wavy.

4 . A gas turbine engine according to claim 3 wherein the inner and/or outer perimeter is a square, pentagon, hexagon, heptagon, octagon, nonagon, decagon, hendecagon or dodecagon.

5 . A gas turbine engine according to claim 3 wherein the tubular containment casing has a polygonal outer and inner perimeter and the containment casing comprises a series of axially-extending wall portions each having a respective radially outer surface and a respective radially inner surface, a series of axially-extending external edges between the outer surfaces of adjoining wall portions and a series of axially-extending internal joins between the inner surfaces of adjoining wall portions.

6 . A gas turbine engine according to claim 5 wherein the number of fan blades in the fan blade assembly is not divisible by the number of wall portions.

7 . A gas turbine engine according to claim 5 wherein each axially extending wall portion has an inner and/or outer surface that is substantially planar.

8 . A gas turbine engine according to claim 1 wherein the tubular containment casing has a corrugated, fluted or wavy outer and inner perimeter and the containment casing comprises an axially-extending tubular wall portion having a radially outer surface and a radially inner surface, and the inner and outer surfaces comprises a series of peaks and troughs defining the corrugations, fluting or waves.

9 . A gas turbine engine according to claim 8 wherein the number of fan blades in the fan blade assembly is not divisible by the number of peaks/troughs in the inner/outer surfaces.

10 . A gas turbine engine according to claim 5 wherein tubular containment casing comprises opposing axial end portions having a circular cross-sectional profile and the wall portion(s) extend(s) between the axial end portions of the containment casing.

11 . A gas turbine engine according to claim 1 wherein the wall portion(s) is/are formed of a fibre-reinforced organic matrix composite.

12 . A gas turbine engine according to claim 1 further comprising a radially outer layer of ballistic wrapping.

13 . A gas turbine engine according to claim 1 further comprising a radially inner liner for defining an annular fan blade path.

14 . A method of making a containment casing for use in a gas turbine engine according to claim 1 , said method comprising:
forming an annular containment casing; and deforming the outer surface of the annular containment casing to form a containment casing having radial cross-sectional profile with a non-circular outer perimeter.

15 . A method according to claim 14 wherein the annular containment casing is formed by ring roll forging of metal.

16 . A method according to claim 14 wherein the annular containment casing is formed by extrusion of metal.

17 . A method according to claim 14 wherein the outer surface of the containment casing is deformed by hydro or superplastic deformation.

18 . A method of making a containment casing for use in a gas turbine engine according to claim 1 , said method comprising a filament or tape winding process using a polygonal, corrugated, fluted or wavy mandrel.

19 . A method according to claim 18 wherein the filament or tape winding process comprises winding dry fibres and then resin transfer moulding (RTM) to cure and achieve the final shape.

20 . A method according to claim 18 wherein the filament or tape winding process comprises winding pre-impregnated tapes of carbon and/or glass and/or aramid and then curing to achieve the final shape.

21 . A method of making a containment casing for use in a gas turbine engine according to claim 1 , said method comprising hot die forging.

Assignees

• Rolls Royce Plc

Inventors

• Finlayson James A
• Evans Dale E
• Care Ian C D

Classifications

• F05D2250/61

  corrugated · CPC title

• F05D2300/603

  Composites; e.g. fibre-reinforced · CPC title

• F05D2250/184

  sinusoidal · CPC title

• F01D21/045 Primary

  special arrangements in stators or in rotors dealing with breaking-off of part of rotor · 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