GB2129501A - Gas turbine engine casing - Google Patents
Gas turbine engine casing Download PDFInfo
- Publication number
- GB2129501A GB2129501A GB08231922A GB8231922A GB2129501A GB 2129501 A GB2129501 A GB 2129501A GB 08231922 A GB08231922 A GB 08231922A GB 8231922 A GB8231922 A GB 8231922A GB 2129501 A GB2129501 A GB 2129501A
- Authority
- GB
- United Kingdom
- Prior art keywords
- casing
- polygonal
- gas turbine
- turbine engine
- polygonal casing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02C—GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS
- F02C7/00—Features, components parts, details or accessories, not provided for in, or of interest apart form groups F02C1/00 - F02C6/00; Air intakes for jet-propulsion plants
- F02C7/20—Mounting or supporting of plant; Accommodating heat expansion or creep
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D25/00—Component parts, details, or accessories, not provided for in, or of interest apart from, other groups
- F01D25/24—Casings; Casing parts, e.g. diaphragms, casing fastenings
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T50/00—Aeronautics or air transport
- Y02T50/60—Efficient propulsion technologies, e.g. for aircraft
Description
1 GB 2 129 501 A 1
SPECIFICATION
Gas turbine engine casing This invention relates to casings for gas turbine- 70 engines of the kind normally used for the propulsion of aircraft.
More particularly, the invention relates to casings which are polygonal in shape.
British patent specification 1,506,952 and the pub- lication ASME Vol 103 October 1981 both disclose polygonal casings and demonstrate that such shapes are better able to cater for out of balance loads and thermally generated loads, in as much as the straight portions of the polygon are placed only in tension or compression when such loads are applied and consequently do not deform. Such a resistance to deformation gives the polygonal casing a distinct advantage over truly circular casings, particularly where the casing is positioned so as to surround a rotating structure, such as a turbine stage. The lack of deformation ensures inter alia greatly reduced if not entirely obviated, turbine blade tip rub.
It should be noted that both of the publications mentioned hereinbefore, refer to both tensile and compressive loads being experienced by a polygonal structure.
The present invention seeks to provide an im- proved polygonal casing structure.
According to the present invention a polygonal casing suitable for use on a gas turbine engine comprises a hub a plurality of spokes radiating outwards from said hub in equi-angularly spaced relationship, each spoke terminating in a flanged cap each pair of adjacent flanged caps being joined via their flanges by a plate which is straight at least in a direction peripherely of the casing, and wherein said flanged caps and plates comprise a sub-assembly which is shrunk onto said spoke ends so as to exert a tensile stress of such magnitude on said plates, that under predictable operating conditions of a gas turbine engine including said casing, tensile stress in said plates would not be obviated.
Preferably the casing includes on its outer 110 periphery means for suspending said casing from aircraft structure.
The boss may comprise a bearing housing Preferably each spoke is surrounded by a sheet 0 metal vane and adjacent vanes may be joined via their roots and tips by annular walls so as to def ine a fluid flow annulus therebetween. At least one of said plates may be corrugated, the pitch of the corrugations being in a direction parallel with the longitudin- al axis of the casing.
The invention will now be described byway of example and with reference to the accompanying drawings in which:- Figure 1 is a diagrammatic view of a gas turbine engine incorporating an embodiment of the invention.
Figure 2 is cross sectional part view on line 2-2 of Figure 1.
Figure 3 is an enlarged partview of an alternative embodiment of the invention, and Figure 4 is a view on line 4-4 of Figure 3.
Referring to Figure 1. A gas turbine engine 10 is suspended from an aircraft wing pylon 12 by means 14 shown diagrammatically atthe upstream end of engine 10 and by a linkage 16 near the downstream end thereof.
Linkage 16 is pivotally connected to a polygonal casing 18 which is more clearly seen in Figure 2.
Referring now to Figure 2. Polygonal casing 18 is constructed from a central hub 20 which in the present example serves as a housing for a turbine shaft bearing (not shown), a number of equiangularly spaced spokes 22 which radiate outwardly from housing 20, end caps 24 each of which is fixed to the end of a respective spoke 22, by welding, set screws or other suitable means, and a number of straight plates 26, which are fixed via their ends, preferably by electron beam welding, to the edges of flanged portions of caps 24, thus defining a spoked boss surrounded by a casing of polygonal profile.
End caps 24 and plates 26 are joined priorto fitting the caps 24 onto the ends of spokes 22. The radially inner ends 30 of caps 24 are then machined to fie in a circle the diameter of which is less than the diameter of the circle on which the ends of spokes 22 lie. The sub assembly of caps 24 and plates 26 is heated until it has expanded sufficiently forthe end caps 24to be slid onto their respective spoke ends.
On cooling of the sub assembly, it shrinks and so presses on the ends of spokes 22, with the result that it becomes immovable.
Itwill be appreciated that when the sub assembly of caps 24 and plates 26 expands through heating, the lengths of the plates 26 will increase. On cooling, spokes 22 will prevent the sub assembly from returning to its original size with the result that plates 26 will be subjected to a permanent tensile stress. The magnitude of the required tensile stress can be calculated by known methods and induced in the polygonal casing by assembling it in the manner described hereinbefore. Similarly the compressive loads likely to be experienced by casing 18 during operation of the gas turbine engine 10 can also be calculated by known methods. The precise interference fit of caps 24to spokes 22 can thus be assessed, which would be required so as to ensure that at least any predictably compressive loads which could be experienced by the casing will never be of such magnitude as to entirely obviate the tensile stress in the plates.
One important aspect of aero engine design, is in the minimising of weight of components whilst maintaining a sufficiency of strength and rigidity. It follows that although calculations may show that a certain minimum thickness of straight plate 26 should be used to achieve the required strength in operation, weight requirements may demand a reduction in that thickness.
Referring now to Figure 3. The polygonal casing 18 should be assumed to have a thickness dictated by weight and includes a plate 26a which is corrugated, the currugations 32 being arranged to run periphirally of casing 18.
In the present example, corrugated plate 26a is positioned so asto be aligned with and connected by 2 GB 2 129 501 A 2 one end to torque link 16a, the specific task of which is to counter any tendency of engine 10 to rotate bodily against its axis in a clockwise direction. Should this occur, despite plate 26a being thinner than is really desirable, it will resist the compressive load it experiences by virtue of the stiffening effect of corrugations 32.
In Figure 4, the corrugations 32 are shown more clearly.
Referring back to Figure 2. It will be appreciated that a polygonal casing does not have a profile which is suitable for providing a gas flow duct. To cater for this spokes 22 are surrounded by thin sheet metal aerofoils 34 joined at their inner and outer ends by thin sheet metal annular wall portions 36, 38. Though not shown, other annular inner casings can be joined via flanges to the upstream and downstream ends of sheet metal wall portions 36, 38, so as to provide the desired flow path.
Claims (9)
1. A polygonal casing suitable for use on a gas turbine engine and comprising a hub, a plurality of spokes radiating outwardly from said hub in equiangularly spaced relationship, each spoke terminating in a flanged cap, each pair of adjacent flanged caps being joined via their flanges by a plate which is straight at least in a direction peripherally of the casing and wherein said flanged caps and plates comprise a sub assembly which is shrunk onto the spoke ends so as to exert a tensile stress of such magnitude on said plates that under predictable operating conditions of a gas turbine engine which includes said casing, tensile stress in said plates is not obviated.
2. A polygonal casing as claimed in claim 1 comprising links for suspending said casing from aircraft fixed structure.
3. A polygonal casing as claimed in claim 1 or claim 2 wherein said hub comprises a bearing housing.
4. A polygonal casing as claimed in any previous claim wherein at least one said plate is corrugated, the length of the corrugations lying in a direction peripherally of said casing.
5. A polygonal casing as claimed in any previous claim wherein each spoke is surrounded by a sheet metal aerofoil vane and adjacent vanes are joined via their radially inner and outer ends by annular wall portions so as to define fluid flow annulus therebetween.
6. A polygonal casing substantially as described in this specification with reference to Figures 1 and 2 of the drawings.
7. A polygonal casing substantially as described in this specification with reference to Figures 3 and 4 of the drawings.
8. A gas turbine engine including a polygonal casing substantially as described in this specification with reference to Figures 1 and 2 of the drawings.
9. A gas turbine engine including a polygonal casing substantially as described in this specification with referenceto Figures 3 and 4 of the drawings.
Printed for Her Majesty's Stationery Office, by Croydon Printing Company Limited, Croydon, Surrey, 1984. Published byThe Patent Office, 25 Southampton Buildings, London, WC2A lAY, from which copies may be obtained.
I e 4 c 1
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB08231922A GB2129501B (en) | 1982-11-09 | 1982-11-09 | Gas turbine engine casing |
US06/540,186 US4492078A (en) | 1982-11-09 | 1983-10-07 | Gas turbine engine casing |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB08231922A GB2129501B (en) | 1982-11-09 | 1982-11-09 | Gas turbine engine casing |
Publications (2)
Publication Number | Publication Date |
---|---|
GB2129501A true GB2129501A (en) | 1984-05-16 |
GB2129501B GB2129501B (en) | 1987-07-08 |
Family
ID=10534127
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB08231922A Expired GB2129501B (en) | 1982-11-09 | 1982-11-09 | Gas turbine engine casing |
Country Status (2)
Country | Link |
---|---|
US (1) | US4492078A (en) |
GB (1) | GB2129501B (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2640319A1 (en) * | 1988-12-14 | 1990-06-15 | Gen Electric | LIGHTWEIGHT GAS TURBINE ENGINE CHASSIS WITH HEAT PROTECTION SCREEN |
EP0519823A1 (en) * | 1991-06-19 | 1992-12-23 | Societe Nationale D'etude Et De Construction De Moteurs D'aviation "Snecma" | Rear suspension structure for a turbine engine |
EP0519822A1 (en) * | 1991-06-19 | 1992-12-23 | Societe Nationale D'etude Et De Construction De Moteurs D'aviation "Snecma" | Suspension structure for a turbo engine exhaust casing |
FR2681401A1 (en) * | 1991-09-16 | 1993-03-19 | Gen Electric | POLYGONAL STRUCTURAL CHASSIS FOR A GAS TURBINE ENGINE WITH AXIALLY CURVED PANELS. |
GB2539093A (en) * | 2015-06-05 | 2016-12-07 | Rolls Royce Plc | Containment casing |
Families Citing this family (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5076049A (en) * | 1990-04-02 | 1991-12-31 | General Electric Company | Pretensioned frame |
US5483792A (en) * | 1993-05-05 | 1996-01-16 | General Electric Company | Turbine frame stiffening rails |
US5406795A (en) * | 1994-01-21 | 1995-04-18 | Cummins Engine Company, Inc. | Exhaust manifold to turbine casing flanges |
US5657633A (en) * | 1995-12-29 | 1997-08-19 | General Electric Company | Centerbody for a multiple annular combustor |
EP1777379A3 (en) * | 2003-07-29 | 2011-03-09 | Pratt & Whitney Canada Corp. | Turbofan case and method of making |
US7100358B2 (en) * | 2004-07-16 | 2006-09-05 | Pratt & Whitney Canada Corp. | Turbine exhaust case and method of making |
US20080016876A1 (en) * | 2005-06-02 | 2008-01-24 | General Electric Company | Method and apparatus for reducing gas turbine engine emissions |
US7909569B2 (en) * | 2005-06-09 | 2011-03-22 | Pratt & Whitney Canada Corp. | Turbine support case and method of manufacturing |
US7594405B2 (en) * | 2006-07-27 | 2009-09-29 | United Technologies Corporation | Catenary mid-turbine frame design |
US8998583B2 (en) | 2008-05-27 | 2015-04-07 | GKNAerospace Sweden AB | Gas turbine engine and a gas turbine engine component |
US8113768B2 (en) | 2008-07-23 | 2012-02-14 | United Technologies Corporation | Actuated variable geometry mid-turbine frame design |
US9003812B2 (en) | 2009-05-08 | 2015-04-14 | Gkn Aerospace Sweden Ab | Supporting structure for a gas turbine engine |
US8776533B2 (en) * | 2010-03-08 | 2014-07-15 | United Technologies Corporation | Strain tolerant bound structure for a gas turbine engine |
US9316108B2 (en) * | 2012-03-05 | 2016-04-19 | General Electric Company | Gas turbine frame stiffening rails |
US10385868B2 (en) * | 2016-07-05 | 2019-08-20 | General Electric Company | Strut assembly for an aircraft engine |
US11028778B2 (en) | 2018-09-27 | 2021-06-08 | Pratt & Whitney Canada Corp. | Engine with start assist |
CN115807697A (en) * | 2023-02-08 | 2023-03-17 | 中国航发沈阳发动机研究所 | Oblique supporting plate bearing frame with deformation coordination function |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2466827A (en) * | 1947-09-09 | 1949-04-12 | Albert W Roth | Roof ventura for fans |
US2524390A (en) * | 1948-09-20 | 1950-10-03 | Hudson Engineering Corp | Fan ring |
US4022018A (en) * | 1975-04-29 | 1977-05-10 | General Electric Company | Mounting system for a thrust generating engine |
GB1506952A (en) * | 1976-04-20 | 1978-04-12 | Rolls Royce | Gas turbine engine support structures |
-
1982
- 1982-11-09 GB GB08231922A patent/GB2129501B/en not_active Expired
-
1983
- 1983-10-07 US US06/540,186 patent/US4492078A/en not_active Expired - Fee Related
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2640319A1 (en) * | 1988-12-14 | 1990-06-15 | Gen Electric | LIGHTWEIGHT GAS TURBINE ENGINE CHASSIS WITH HEAT PROTECTION SCREEN |
GB2226086A (en) * | 1988-12-14 | 1990-06-20 | Gen Electric | Gas turbine engine frame |
GB2226086B (en) * | 1988-12-14 | 1993-02-17 | Gen Electric | Gas turbine engine frame |
EP0519823A1 (en) * | 1991-06-19 | 1992-12-23 | Societe Nationale D'etude Et De Construction De Moteurs D'aviation "Snecma" | Rear suspension structure for a turbine engine |
EP0519822A1 (en) * | 1991-06-19 | 1992-12-23 | Societe Nationale D'etude Et De Construction De Moteurs D'aviation "Snecma" | Suspension structure for a turbo engine exhaust casing |
FR2677954A1 (en) * | 1991-06-19 | 1992-12-24 | Snecma | REAR SUSPENSION STRUCTURE OF THE EXHAUST CASING OF A TURBOJET. |
FR2677953A1 (en) * | 1991-06-19 | 1992-12-24 | Snecma | REAR SUSPENSION STRUCTURE OF A TURBOREACTOR. |
US5190245A (en) * | 1991-06-19 | 1993-03-02 | Societe Nationale D'etude Et De Construction De Moteurs D'aviation "S.N.E.C.M.A." | Turbojet engine exhaust casing with integral suspension lugs |
US5259183A (en) * | 1991-06-19 | 1993-11-09 | Societe Nationale D'etude Et De Construction De Moteurs D'aviation "S.N.E.C.M.A." | Turbojet engine exhaust casing with integral suspension lugs |
FR2681401A1 (en) * | 1991-09-16 | 1993-03-19 | Gen Electric | POLYGONAL STRUCTURAL CHASSIS FOR A GAS TURBINE ENGINE WITH AXIALLY CURVED PANELS. |
GB2539093A (en) * | 2015-06-05 | 2016-12-07 | Rolls Royce Plc | Containment casing |
US10428681B2 (en) | 2015-06-05 | 2019-10-01 | Rolls-Royce Plc | Containment casing |
Also Published As
Publication number | Publication date |
---|---|
US4492078A (en) | 1985-01-08 |
GB2129501B (en) | 1987-07-08 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4492078A (en) | Gas turbine engine casing | |
US9003812B2 (en) | Supporting structure for a gas turbine engine | |
US3294366A (en) | Blades for gas turbine engines | |
US7770378B2 (en) | Turbofan case and method of making | |
US7793488B2 (en) | Turbofan case and method of making | |
EP2336500B1 (en) | Method of manufacturing an inlet assembly for an aircraft engine | |
EP2142761B1 (en) | A gas turbine engine component, a turbojet engine provided therewith, and an aircraft provided therewith | |
US3745629A (en) | Method of determining optimal shapes for stator blades | |
JP4776818B2 (en) | Platform guide vanes with matching shapes | |
GB2164098A (en) | Improvements in or relating to aerofoil section members for turbine engines | |
CN110199090B (en) | Thermal insulation structure for rotating turbine frame | |
WO2011019412A2 (en) | Turbine blade having a constant thickness airfoil skin | |
US10196980B2 (en) | Bearing outer race retention during high load events | |
EP3225792A1 (en) | Attachment system between a strut and an engine casing | |
JP5732067B2 (en) | Propeller hub with reinforced polygonal ring and turbine engine provided with such a hub | |
CN109695480B (en) | Turbine engine including straightening assembly | |
EP3179119B1 (en) | Thrust bearing assembly with flow path restriction | |
GB2049069A (en) | Rotor assembly for a gas turbine engine | |
US10724390B2 (en) | Collar support assembly for airfoils | |
CN114607472A (en) | Variable stator vane with anti-lock trunnion | |
CA3135720A1 (en) | Turbine casing for gas turbine engine |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19961109 |