WO2016076856A1

WO2016076856A1 - Threaded combustor housing with union nut

Info

Publication number: WO2016076856A1
Application number: PCT/US2014/065231
Authority: WO
Inventors: William W. Pankey
Original assignee: Siemens Energy, Inc.
Priority date: 2014-11-12
Filing date: 2014-11-12
Publication date: 2016-05-19

Abstract

Disclosed are an arrangement of a casing component and a combustor component, a method of attaching a casing component to a combustor component, and an engine including the arrangement. The arrangement includes a spanner nut which retains the casing component from within the combustor component. The method includes inserting the casing component into a smooth bore of the combustor component and retaining the casing component within the combustor component using the spanner nut until the casing component flange abuts the combustor component flange.

Description

THREADED COMBUSTOR HOUSING WITH UNION NUT

BACKGROUND

1. Field [0001] The present application relates to gas turbines, and more particularly to a method of attaching a casing component to a combustor component, an engine, as well as a combustor arrangement including a spanner nut.

2. Description of the Related Art [0002] Cylindrical components are typically attached to one another with a flanged bolted joint. In a gas turbine, a casing component, typically referred to as a tophat, is attached to a combustor casing with a plurality of bolts. Through holes are installed in the tophat flange and threaded holes are installed in the combustor casing to accept bolts that are installed through the tophat and into the combustor casing. Typically, approximately 24 holes, each with a corresponding bolt, per combustor casing may be used. Bolts shearing, case thread galling, and improper assembly may result in damage to threaded features and may increase the service time to the combustor and the outage time of the gas turbine. Incremental costs to replace the damaged components may also be an issue.

SUMMARY

[0003] Briefly described, aspects of the present disclosure relates to a casing component and a combustor component arrangement, a method of attaching a casing component to a combustor component, and an engine. [0004] A first aspect provides an arrangement of a casing component and a combustor component. The arrangement includes a combustor component including a cylindrical portion where the cylindrical portion includes a smooth bore. In addition, the arrangement includes a casing component, a portion of which fits within the smooth bore of the combustor component. Lastly, the arrangement includes a spanner nut wherein the spanner nut retains the casing component from within the combustor component.

[0005] A second aspect provides a method of attaching a casing component to a combustor component including inserting the casing component into a smooth bore of the combustor component and retaining the casing component within the combustor component using a spanner nut until the casing component flange abuts the combustor component flange.

[0006] A third aspect of provides an engine including a compressor section, a turbine section, and a combustor section including an arrangement of a casing component and a combustor component. The arrangement includes a combustor component including a cylindrical portion where the cylindrical portion includes a smooth bore. In addition, the arrangement includes a casing component, a portion of which fits within the smooth bore of the combustor component. Lastly, the arrangement includes a spanner nut wherein the spanner nut retains the casing component from within the combustor component.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIG 1 illustrates a side view of a casing component attached to a combustor casing with a flanged bolted joint, [0008] FIG 2 illustrates an exploded view of a casing component including through holes and the combustor casing including case bolt holes,

[0009] FIG 3 illustrates an interior view of a combustor arrangement,

[0010] FIG 4 illustrates a cross sectional view of the combustor arrangement of FIG 3, [0011] FIG 5 illustrates a cross sectional view of the combustor component only of FIG 3, and [0012] FIG 6 illustrates a tool used to tighten the spanner nut.

DETAILED DESCRIPTION

[0013] To facilitate an understanding of embodiments, principles, and features of the present disclosure, they are explained hereinafter with reference to implementation in illustrative embodiments. Embodiments of the present disclosure, however, are not limited to use in the described systems or methods.

[0014] The components and materials described hereinafter as making up the various embodiments are intended to be illustrative and not restrictive. Many suitable components and materials that would perform the same or a similar function as the materials described herein are intended to be embraced within the scope of embodiments of the present disclosure.

[0015] A method, an engine, and an arrangement to attach a casing component to a combustor casing are provided. This method and arrangement could minimize the amount of threaded features in the combustor casing. Minimization of the threaded features may result in a shorter turnaround time to service the combustor as each time the casing component is removed, a plurality of fasteners need to be removed which potentially can be, for example, 24 bolts per combustor and with 16 combustors per engine typically, approximately 384 bolts may need to be removed. In addition, the minimization of the bolts and the corresponding washers may also have a cost sa ving by not including this additional hardware. Furthermore, machining the combustor casing in order to include the holes for the fasteners and/or to eliminate faulty threads may be dispensed with using the provided arrangement and method. It will be appreciated to one skilled in the art that the attachment method and arrangement may be desirable anywhere a flanged joint arrangement is used. An engine is also provided. The engine includes a compressor section, a combustor section including a plurality of burners where each burner includes the arrangement, and a turbine section. The casing component may attach to any casing that includes an interface that corresponds to the flange of the casing component so that they may be mated. For illustrative purposes, the casing component is described hereinafter as a tophat component that attaches to a combustor casing. A tophat and a corresponding combustor casing within which at least a portion of the tophat fits secured by a spanner nut are provided as a different embodiment to the threaded features of the conventional arrangement.

[0016] FIG 1 illustrates a side view of a conventional attachment (10) of a combustor casing (30) to a tophat component (20). Conventionally, the attachment of the tophat component (20) to a combustor casing (30) uses a flanged joint (40) where the tophat flange (50) is secured by fasteners (60). FIG 2 shows an exploded view of the tophat (20) and the combustor casing (30) with a plurality of bolts (60) before inserting them through the corresponding holes (70) in the tophat (20) and holes in the combustor casing (80). According to this illustration, the bolts (60) are evenly spaced around the circumference of the tophat flange (50). In the conventional arrangement (10), a typical tophat inner diameter would be in a range of 460 to 470 mm with a somewhat restricted fluid flow through the flow passage area of the tophat (20). For the conventional arrangement (10), if the radial thickness of the tophat is reduced to increase the fluid flow through the tophat (20), the radial thickness may not be appropriate to support a wider tophat flange (50) which includes holes (70). Cracking may also occur.

[0017] FIG 3 illustrates a cross sectional view of an embodiment of a combustor arrangement (100) including a combustor component (130) with an attached tophat component (120) and a spanner nut (140). FIG 4 shows an exploded view of a portion of the combustor component (130), the tophat component (120), and the spanner nut (140) of FIG 3. FIG 5 shows a cross sectional view of FIG 4 showing only the combustor casing without the tophat component.

[0018] In the illustrated embodiment shown in FIG 5, the combustor component (130), also known as the combustor housing, includes a cylindrical portion (170) including a smooth bore (180). The cylindrical portion (170) includes an outer diameter (195) and an inner diameter (185) defining a radial thickness (t₁).

[0019] The tophat component (120) illustrated in the shown embodiments of FIGs 3 and 4 is also a hollow cylindrical component with a radial thickness (t₂) and includes an outer diameter (125) and an inner diameter (115). A range for the inner diameter (115) of the tophat component (120) may be 460mm - 520mm. In another embodiment the range may be 490mm - 520mm. This inner diameter range may present an increase over the inner diameter range of the tophat component (20) for the conventional arrangement (10). An increased inner diameter would increase the cross sectional area of the tophat component and potentially increase the fluid flow through the tophat component (120). An increased fluid flow would thus increase the efficiency of the gas turbine. As shown in FIG 4, a portion of the length of the tophat (120) fits within the combustor component (130) such that the outer diameter (125) of the tophat is coaxial with the inner diameter (185) of the combustor housing (130). [0020] In an embodiment, in order to retain the tophat (120) within the combustor component (130), a spanner nut (140) may be used. The spanner nut (140) retains the tophat (120) from within the combustor component (130). The spanner nut (140) may include threads on at least a portion of an inner surface that correspond to a threaded portion of the tophat component (120). In an embodiment only an end portion of an outer surface of the tophat component (120) includes threads such that the spanner nut (140) may be fastened to the tophat (120) within the combustor component (130). In another embodiment, an inner surface may include the threads that correspond to a spanner nut.

[0021] The spanner nut (140) may also abut the combustor component (130) on a non-threaded side of the spanner nut (140). The abutment would occur at a landing within the combustor component (130). In an embodiment, as shown in FIG 5, the landing may be provided as a recess (190) and may match the contacting surface of the nut such that the surfaces mate.

[0022] In an embodiment, the combustor component (130) may include a lip (160) onto which a flange (150) of the tophat component (120) abuts. At this abutment interface between the tophat component (120) and the combustor component (130) a sealing occurs. Due to the torque applied to the spanner nut when tightening, the spanner nut (140) provides the force for the sealing between the tophat component (120) and combustor component (130) by pulling the tophat flange (150) tight against the lip (160) of the combustor component (130). [0023] The spanner nut (140) may be attached to the tophat component (120) and appropriately tightened using a torque-multiplier type tool (200). An example of a torque-multiplier tool (200) is shown in FIG 6. The torque-multiplier tool (200) shown is a manual type tool with gear reduction stages. However, powered forms of the tool may also be used.

[0024] The arrangement (100) of the tophat (120) and the combustor component (130) and engine including the arrangement (100) include different features than the conventional arrangement (10) using a flanged joint (40). The radial thickness of the tophat component (t?) could be thinner than the conventional arrangement (10) using the provided arrangement (100) with a spanner nut (140) as the wider flange (50) of the conventional arrangement with bolt holes (70) requires a thicker cylindrical wall due to material requirements. Using less material for the tophat component (120) could result in a cost savings. In addition, the tophat flange (150) would not need to be as wide to accommodate holes and corresponding fasteners. A narrow tophat flange (150) may be used in the provided arrangement as illustrated in FIGs 3 and 4.

[0025] The elimination of holes and the corresponding fastening could also allow for an increased cross-sectional area of the combustor component bore which may potentially increase the fluid flow through the combustor and also reduce the pressure loss of the air flowing into the combustor. As mentioned above, the inner diameter (1 15) of the tophat component (120) may be in a range of 460mm to 520mm. An inner diameter of a conventional arrangement (10) as shown in FIGs 1 and 2 would be approximately 460mm. For this example, the increase in fluid flow using the arrangement shown in FIGs 3 and 4 may be as much as 35% over the conventional arrangement (10). Increased fluid flow through the combustor could increase the efficiency of the combustor. Also, in the engine, which includes a number of combustor arrangements arranged around an engine centerline, the combustor housings could be angled to be closer to the engine centerline reducing the diameter of the midframe. A reduced midframe diameter allows the engine to be transported easier.

[0026] Referring to FIGs 1-5, a method for attaching a casing component (120) to a combustor component (130) is also provided. The tophat component (120) would be inserted into a smooth bore (180) of the combustor component (130), A portion of the length of the tophat component (120) as shown in FIGs 3 and 4 would fit within the combustor housing (130) such that the outer diameter (125) of the tophat component (120) is coaxial with the inner diameter (185) of the combustor component (130). The tophat component (120) would then be retained within the combustor component (130) by a spanner nut (140) until the tophat flange (150) abuts the combustor component lip (160).

[0027] in order to retain the tophat component (120) to a combustor component (130), the spanner nut (140) may be inserted from within the combustor component (130). in an embodiment, a non-threaded side of the spanner nut (140) would abut the combustor component (130) at a landing within the combustor component (130). The landing may be a recess (190). A threaded side of the spanner nut (140) would be threaded onto a corresponding threaded end portion on the outer surface of the tophat component (120), [0028] In an embodiment, the spanner nut (140) is tightened in order to secure the casing component (120) to the combustor housing (130) such that a sealing occurs at the interface of the lip (160) of the combustor component (130) and a flange (150) of the tophat component (120). The spanner nut (140) provides the force for the sealing between the tophat component (120) and combustor component (130) by pulling the tophat flange (150) tight against the lip (160) of the combustor component (130),

[0029] In order to tighten the spanner nut (140) within the combustor component, a tool may be attached to the spanner nut (140), however, one skilled in the art would understand that other steps may be taken to tighten the spanner nut (140) on the tophat component (120). In the illustrated embodiment shown in FIG 5, a torque multiplier- type wrenching tool (200) may be used to tighten the spanner nut. The tool shown is a manual type tool with multiple gear reduction stages. Powered forms of this tool may also be used. The spanner nut is then torqued to an appropriate tightness.

[0030] Additionally, tensioning may be used to secure the spanner nut (140) within the combustor component (130) to the casing component (120). A tensioning tool would be used to tension the casing component while the spanner nut (140) is secured onto the casing component (120). The tensioning tool would then release the casing component providing an appropriate air tight and pressure tight seal at the abutment of a flange (150) of the casing component and the lip (160) of the combustor component (130). [0031] The method provides a quicker way to attach the tophat component (120) to the combustor component (130) than the conventional arrangement (10). The sealing at the interface between the lip (160) of the combustor component (130) and the flange (150) of the tophat component (120) may be accomplished with one nut instead of a plurality of fasteners and corresponding nuts. Additionally,, the method provides a way to attach the tophat component (120) to the combustor component (130) without drilling holes directly into the combustor component (130) which is a costly component.

[0032] While embodiments of the present disclosure have been disclosed in exemplary forms, it will be apparent to those skilled in the art that many modifications, additions, and deletions can be made therein without departing from the spirit and scope of the invention and its equivalents, as set forth in the following claims.

Claims

What is claimed is:

1. An arrangement (100) of a casing component (120) and a combustor component (130) comprising:

a combustor component (130) including a cylindrical portion (170), the cylindrical portion (170) including a smooth bore (180);

a casing component (120), a portion of which fits within the smooth bore (180) of the combustor component (130); and

a spanner nut (140),

wherein the spanner nut (140) retains the casing component (120) from within the combustor component (130).

2. The arrangement (100) as claimed in claim 1, wherein at least a portion of the casing component (120) is a cylindrical component.

3. The arrangement (100) as claimed in claim 2, wherein at least a portion of the casing component (120) is threaded on an outer surface.

4. The arrangement (100) as claimed in claim 3, wherein at least a portion of the spanner nut (140) is threaded on an inside surface to accommodate the threading of the casing component (120).

5. The arrangement (100) as claimed in claims 2-4, wherein the outer diameter (125) of the casing component (120) and the inner diameter (185) of the combustor component (130) are coaxial.

6. The arrangement (100) as claimed in claim 5, wherein an inner diameter (115) of the casing component (120) is in a range of 460 mm - 520 mm.

7. The arrangement (100) as claimed in the previous claims,

wherein the casing component (120) comprises a flange (150) and the combustor component comprises a lip (160), and

wherein the flange (150) abuts the lip (160).

8. The arrangement (100) as claimed in claim 7, wherein a sealing occurs at the abutment of the flange (150) and the lip (160).

9. The arrangement (100) as claimed in claim 8, wherein the spanner nut (140) provides a force which creates an air tight and pressure tight sealing between the flange (150) and the combustor component lip (160).

10. The arrangement (100) as claimed in claim 6, wherein a hollow portion of the casing component (120) has increased flow passage area wherein the increase is created by a reduced radial thickness of the casing component (120) caused by an el imination of bolt holes in the flange (150).

11. The arrangement as claimed in the previous claims, wherein an outer non-threaded portion of the spanner nut (140) abuts the combustor component (130).

12. The arrangement as claimed in claim 11, wherein the outer non- threaded portion abuts the combustor component at a landing.

13. The arrangement as claimed in claim 12, wherein the landing is a recess (190).

14. A method of attaching a casing component (120) to a combustor component (130) comprising:

inserting the casing component (120) into a smooth bore (180) of the combustor component (130); and

retaining the casing component (120) within the combustor component (130) using a spanner nut (140) until a casing component flange (150) abuts a combustor component lip (160).

15. The method as claimed in claim 14, wherein the retaining includes inserting the spanner nut (140) from within the combustor component (130).

16. The method as claimed in claims 14 and 15, wherein the retaining includes tightening the spanner nut (140) within the combustor component (130).

17. The method as claimed in claim 14, wherein the retaining includes tensioning the casing component (120) via a tensioning device followed by securing the spanner nut (140).

18. The method as claimed in claims 14-17, wherein at least a portion of the casing component (120) is a cylindrical component.

19. The method as claimed in claim 18, wherein at least a portion of the casing component (120) is threaded on an outer surface.

20. The method as claimed in claim 19, wherein at least a portion of the spanner nut (140) is threaded on an inside surface to accommodate the threading of the casing component (120).

21. The method as claimed in claims 18-20, wherein the outer diameter (125) of the casing component (120) and the inner diameter (185) of the combustor component (130) are coaxial.

22. The method as claimed in claim 21, wherein an inner diameter (115) of the casing component (120) is in a range of 460 mm - 520 mm.

23. The method as claimed in claims 14-22,

wherein the flange (150) abuts the lip (160).

24. The method as claimed in claim 23, wherein a sealing occurs at the abutment of the flange (150) and the lip (160).

25. The method as claimed in claim 24, wherein the spanner nut (140) provides a force which creates an air tight and pressure tight sealing between the flange (150) and the combustor component lip (160).

26. The method as claimed in claim 22, wherein a hollo w portion of the casing component (120) has increased flow passage area wherein the increase is created by a reduced radial thickness of the casing component (120) caused by an elimination of bolt holes in the flange (150).

27. The method as claimed in claims 14-26, wherein an outer non-threaded portion of the spanner nut (140) abuts the combustor component (130 ).

28. The method as claimed in claim 27, wherein the outer non-threaded portion abuts the combustor component at a landing.

29. The method as claimed in claim 28, wherein the landing is a recess (190).

30. The method as claimed in claims 14-29, wherein a threaded inner portion of the spanner nut (140) is threaded onto threads of an outer portion of the casing component (130).

31. An engine comprising:

a compressor section;

a turbine section;

a combustor section comprising,

a combustor component (130) including a smooth bore (180);

a casing component (120), a portion of which fits within the smooth bore (180) of the combustor component 130); and

a spanner nut (140),

32. The engine as claimed in claim 31 , wherein at least a portion of the casing component (120) is a cylindrical component.

33. The engine as claimed in claim 32, wherein at least a portion of the casing component (120) is threaded on an outer surface.

34. The engine as claimed in claim 33, wherein at least a portion of the spanner nut (140) is threaded on an inside surface to accommodate the threading of the casing component (120).

35. The engine as claimed in claims 32-34, wherein the outer diameter (125) of the casing component (120) and the inner diameter (185) of the combustor component (130) are coaxial.

36. The engine as claimed in claim 35, wherein an inner diameter (115) of the casing component (120) is in a range of 460 mm - 520 mm.

37. The engine as claimed in claims 31-36,

wherein the flange (150) abuts the lip (160).

38. The engine as claimed in claim 37, wherein a sealing occurs at the abutment of the flange (150) and the lip (160).

39. The engine as claimed in claim 31 , wherein the spanner nut (140) provides a force which creates an air tight and pressure tight sealing between the flange (150) and the combustor component lip (160).

40. The engine as claimed in claim 31 , wherein a hollow portion of the casing component (120) has increased flow passage area wherein the increase is created by a reduced radial thickness of the casing component (120) caused by an elimination of bolt holes in the flange (150).

41. The engine as claimed in claims 31-40, wherein an outer non-threaded portion of the spanner nut (140) abuts the combustor component (130).

42. The engine as claimed in claims 31-41 , wherein the outer non-threaded portion abuts the combustor component at a landing.

43. The engine as claimed in claim 42, wherein the landing is a recess

(190).