Turboshaft engine inclusive hot end casing and turbine engine with same

Abstract

The invention discloses a turboshaft engine inclusive hot end casing and a turbine engine with the same. The turboshaft engine inclusive hot end casing comprises a hot end outer casing, an inner casing and a gas turbine casing. The hot-end outer casing comprises a casing front mounting section, a casing head and a power turbine section which are integrally designed and are connected through two circumferential electron beams arranged in sequence in an annular welding mode so that the hot-end outer casing can form the integrated hot-end outer casing. The gas turbine casing and the inner casing are arranged in a sleeved mode, and the gas turbine casing, the inner casing, the flame tube inner ring, the flame tube outer ring and the hot end outer casing are matched to form a multi-layer wall face to contain gas turbine blades. The power turbine section is also subjected to containment design to contain power turbine blades. According to the casing, the number of mounting edges and welding seams can be greatly reduced, the weight of the hot-end outer casing is further reduced, the manufacturing cost is reduced, damage to an engine caused by broken and flying blades is effectively prevented, the working safety of the engine is improved, and the service life of the engine is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of turboshaft engines, and in particular to a turboshaft engine containing hot end casing. Furthermore, the present invention also relates to a turbine engine comprising the turboshaft engine containing hot end casing. Background Art

[0002] The operating environment temperature of the engine's hot-end outer casing, inner casing, and gas turbine casing is relatively high. These components are hot-end components, and the hot-end outer casing is also a load-bearing and pressure-bearing part. For civil engines, not only technical and airworthiness success are required, but also commercial success. Lifespan is one of the key factors affecting the lifecycle cost of an engine. Therefore, when designing the engine's hot-end outer casing, inner casing, and gas turbine casing, lifespan and cost are key considerations. Furthermore, airworthiness regulations clearly stipulate that the engine's outer casing must be tolerant to damage caused by rotor blade failure. Therefore, when designing the engine's hot-end casing, tolerant design must also be considered.

[0003] The hot end outer casing of an engine is usually composed of a combustion chamber outer casing and a turbine outer casing connected by bolts. The split design of the hot end outer casing of the engine not only has more connecting mounting edges, but also has a large number of welds on the hot end outer casing. This results in a heavy weight of the hot end outer casing of the engine and a relatively high total manufacturing cost. When the design is unreasonable, problems such as cracks in the mounting seat welds, deformation of the nozzle mounting end face, and cracking of the mounting edge may occur. On the other hand, when the wall thickness is not selected reasonably, there is a possibility that the flying broken blades caused by failure of the rotor blades cannot be accommodated, or the wall thickness is too thick, which greatly increases the weight and cost of the casing. In addition, the anti-loosening structure of the nozzle fastening screws on some engine hot end outer casings has poor maintainability and high maintenance costs. Summary of the Invention

[0004] The present invention provides a turboshaft engine inclusive hot end casing and a turbine engine having the same, so as to solve the technical problem that the existing split-type engine hot end outer casing not only has a large number of connection and installation edges, but also has a large number of welds on the hot end outer casing, which leads to a heavy weight of the engine hot end outer casing and a relatively high total manufacturing cost. In addition, when the wall thickness is not selected reasonably, there is a technical problem that it cannot contain the flying broken blades caused by the failure of the rotor blades.

[0005] The technical solution adopted in the present invention is as follows: The invention relates to a turboshaft engine containing hot-end casing, comprising: a hot-end outer casing of a full-ring structure, an inner casing and a gas turbine casing; the hot-end outer casing comprises a casing front mounting section, a casing head section and a power turbine section arranged in sequence along the axial direction, the casing front mounting section, the casing head section and the power turbine section are respectively designed as an integrated whole, and the three are welded together by two circumferential electron beam ring weldings arranged in sequence to form an integrated hot-end outer casing, and a combustion chamber peephole seat, a turbine peephole seat and a plurality of mounting seats are also connected to the hot-end outer casing by electron beam welding; the gas turbine casing and the inner casing are arranged in an inner and outer manner and connected to the hot-end outer casing, and the gas turbine casing, the inner casing, the flame tube inner ring and the flame tube outer ring connected to the hot-end outer casing and arranged in an inner and outer manner, and the hot-end outer casing cooperate to form a multi-layer wall surface arranged in sequence from the inside to the outside to contain the gas turbine blades; the power turbine section is also designed to be inclusive to contain the power turbine blades.

[0006] Furthermore, the diffuser casing is axially arranged upstream of the front mounting section of the casing, the auxiliary mounting section is sleeved outside the front mounting section of the casing, and the rear mounting edge of the diffuser casing, the front mounting edge of the front mounting section of the casing and the auxiliary mounting section are connected and locked by fastening bolts passing through the three and self-locking nuts sleeved on the outer circle of the fastening bolts.

[0007] Furthermore, the annular wall thickness δ1 of the front mounting section of the casing near its front mounting edge is 1.5mm to 3mm; the outer diameters of the outer edge surfaces of the rear mounting edge of the diffuser casing and the front mounting edge of the front mounting section of the casing are equal, and the distance L1 between the outer edge surfaces of the two and the center of the fastening bolt is 6mm to 9mm.

[0008] Furthermore, the inner surface of the power turbine section is a stepped surface arranged along the axial direction; the wall thickness δ2 of the power turbine section corresponding to the power turbine is 5mm~8mm; and the distance L2 between the rear exhaust edge of the power turbine section and the axial end of the power turbine is 10mm~15mm.

[0009] Furthermore, a flame tube head connecting the flame tube inner ring and the flame tube outer ring is provided in the hot end outer casing, and the flame tube head is also connected to a nozzle; the nozzle mounting section for mounting the nozzle is vertically arranged on the casing head, and the nozzle is fixed to the nozzle mounting section by a fastening screw, and a wire thread sleeve is also provided on the fastening screw to prevent rotation.

[0010] Furthermore, the wall surface of the nozzle installation section where the nozzle is installed is locally thickened so that the local wall thickness δ3 after the thickening design is 7 to 9 mm; the wall surface of the nozzle installation section where the fastening screw is installed is locally thickened so that the local wall thickness δ4 after the thickening design is 11 to 13 mm.

[0011] Furthermore, the outer ring of the flame tube is also fixed to the front mounting section of the receiver by a plurality of fixing pins evenly distributed circumferentially; the multiple mounting seats include two nozzle mounting seats and two nozzle seats, the two nozzle mounting seats are fixed on the outer wall surface of the front mounting section of the receiver at intervals along the circumference, and the two nozzle seats are fixed on the outer wall surface of the outer ring of the flame tube at intervals along the circumference, and the two nozzle seats are arranged corresponding to the two nozzle mounting seats; each nozzle mounting seat is provided with an ignition nozzle, and the bottom end of the ignition nozzle is inserted into the corresponding nozzle seat.

[0012] Furthermore, the centers of the two ignition nozzles coincide with the centers of the main combustion holes on the outer ring of the flame tube respectively; the first ignition nozzle is located directly above the engine, and the projection of the first ignition nozzle in the vertical plane perpendicular to the axis is located between the projections of the two adjacent mounting pins in the vertical plane; the second ignition nozzle is located on one side directly below the engine.

[0013] Furthermore, the first ends of the inner casing and the gas turbine casing are circumferentially locked and fixed by multiple sets of fastening bolts and flared self-locking nuts in the casing head; the second ends of the inner casing and the gas turbine casing extend toward the free end of the inner ring of the flame tube, and the second end of the inner casing is overlapped and connected to the free end of the inner ring of the flame tube through an overlapping edge.

[0014] According to another aspect of the present invention, there is also provided a turbine engine having a turboshaft engine inclusive hot end casing as described above.

[0015] The present invention has the following beneficial effects: Compared with the prior art, the combustion chamber outer casing and the turbine outer casing are respectively formed by welding multiple sections of casings, and the combustion chamber outer casing and the turbine outer casing are also detachably connected by mounting edges and several groups of connecting bolts. In the inclusive hot end casing of the turboshaft engine of the present invention, the casing front mounting section, the casing head and the power turbine section are respectively formed by integrated design and processing, and the casing front mounting section, the casing head and the power turbine section are also connected by two circumferential electron beam ring weldings arranged in sequence, so that the hot end outer casing forms an integrated hot end outer casing, which not only greatly reduces the number of mounting edges and welds, thereby reducing the weight of the hot end outer casing and reducing manufacturing costs, but also makes the overall structure of the hot end outer casing stable and less prone to welds. Cracks and welding deformations are prevented, thereby prolonging the service life of the hot end outer casing; on the other hand, for civil engines, the airworthiness clauses clearly stipulate that the engine outer casing must be tolerant to damage caused by failure of the rotor blades. Therefore, in the casing structure of the present invention, the gas turbine casing, the inner casing, the inner ring of the flame tube, the outer ring of the flame tube and the hot end outer casing are coordinated to form a multi-layer wall arranged from the inside to the outside to contain the gas turbine blades. At the same time, an inclusive design is also carried out in the power turbine section to contain the power turbine blades, thereby achieving the containment of the gas turbine blades and the power turbine blades that are broken by flying, effectively preventing the broken flying blades from damaging the engine, improving the safety of the engine operation and extending its service life.

[0016] In addition to the above-described objects, features and advantages, the present invention has other objects, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings: Figure 1 This is a schematic diagram of the main structure of the turboshaft engine inclusive hot end casing according to a preferred embodiment of the present invention; Figure 2 yes Figure 1 Schematic diagram of the assembly and connection between the middle diffuser casing and the auxiliary mounting section and the hot end outer casing; Figure 3 yes Figure 1 Schematic diagram of the inclusive structural design of the medium power turbine section; Figure 4 yes Figure 1 Schematic diagram of the projection of the center locating pin and ignition nozzle in the vertical plane; Figure 5 yes Figure 1 Schematic diagram of the position of the nozzle mounting base; Figure 6 yes Figure 1 Schematic diagram of the structure of the middle receiver head; Figure 7 yes Figure 6 Partial schematic diagram of the structure in the middle left view.

[0018] Legend: 1. Hot end outer casing; 11. Casing front mounting section; 12. Casing head; 121. Nozzle mounting section; 122. Nozzle mounting hole; 123. Bolt mounting hole; 13. Power turbine section; 131. Rear exhaust edge; 14. Electron beam girth welding; 15. Combustion chamber peephole seat; 16. Turbine peephole seat; 17. Retaining pin; 18. Nozzle mounting seat; 19. Nozzle seat; 31. Inner casing; 311. Overlapping edge; 32. Gas turbine casing; 33. Diffuser casing; 34. Auxiliary mounting section; 35. Fastening bolts; 36. Self-locking nuts; 41. Inner ring of flame tube; 42. Outer ring of flame tube; 51. Gas turbine blades; 52. Power turbine blades; 61. Ignition nozzle. DETAILED DESCRIPTION

[0019] The embodiments of the present invention are described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0020] Reference Figure 1 A preferred embodiment of the present invention provides a turboshaft engine enclosed hot-end casing, comprising: a full-ring hot-end outer casing 1, an inner casing 31, and a gas turbine casing 32. The hot-end outer casing 1 comprises a casing front mounting section 11, a casing head 12, and a power turbine section 13, which are sequentially arranged along the axial direction. The casing front mounting section 11, the casing head 12, and the power turbine section 13 are each integrally designed and welded together via two circumferential electron beam girth welds 14, forming an integrated hot-end outer casing 1. A combustion chamber peephole seat 15, a turbine peephole seat 16, and various mounting seats are also electron beam welded to the hot-end outer casing 1. The gas turbine casing 32 and the inner casing 31 are arranged in an inner and outer manner and connected to the hot end outer casing 1. The gas turbine casing 32, the inner casing 31, the flame tube inner ring 41 and the flame tube outer ring 42 connected to the hot end outer casing 1 and arranged in an inner and outer manner, and the hot end outer casing 1 cooperate to form a multi-layer wall arranged sequentially from the inside to the outside to accommodate the gas turbine blades 51. The power turbine section 13 is also designed to be inclusive to accommodate the power turbine blades 52.

[0021] Compared with the prior art, the combustion chamber outer casing and the turbine outer casing are respectively formed by welding multiple sections of casings, and the combustion chamber outer casing and the turbine outer casing are also detachably connected by mounting edges and several groups of connecting bolts. In the inclusive hot end casing of the turboshaft engine of the present invention, the casing front mounting section 11, the casing head 12 and the power turbine section 13 are respectively formed by integrated design and processing, and the casing front mounting section 11, the casing head 12 and the power turbine section 13 are also welded and connected by two circumferential electron beam ring weldings 14 arranged in sequence, so that the hot end outer casing 1 forms an integrated hot end outer casing 1, which not only greatly reduces the number of mounting edges and welds, thereby reducing the weight of the hot end outer casing and reducing manufacturing costs, but also makes the overall structure of the hot end outer casing stable and not prone to weld cracks. and welding deformation, thereby increasing the service life of the hot end outer casing; on the other hand, for civil engines, the airworthiness clauses clearly stipulate that the engine outer casing must be inclusive of damage caused by failure of the rotor blades. Therefore, in the casing structure of the present invention, the gas turbine casing 32, the inner casing 31, the flame tube inner ring 41, the flame tube outer ring 42 and the hot end outer casing 1 are coordinated to form a multi-layer wall arranged from the inside to the outside to contain the gas turbine blades 51. At the same time, the power turbine section 13 is also designed to be inclusive to contain the power turbine blades 52, thereby achieving the containment of the gas turbine blades 51 and the power turbine blades 52 that are broken by flying, effectively preventing the broken flying blades from damaging the engine, improving the safety of the engine operation and extending its service life.

[0022] Alternatively, as Figure 2 As shown, the diffuser casing 33 is arranged axially upstream of the casing front mounting section 11, the auxiliary mounting section 34 is sleeved outside the casing front mounting section 11, and the rear mounting edge of the diffuser casing 33, the front mounting edge of the casing front mounting section 11 and the auxiliary mounting section 34 are connected and locked by fastening bolts 35 passing through the three and self-locking nuts 36 sleeved on the outer circle of the fastening bolts 35. In this optional solution, if Figure 2 As shown, the hot end outer casing 1, the diffuser casing 33 and the auxiliary mounting joint 34 are designed as separate parts, and are connected and locked by fastening bolts 35 and self-locking nuts 36, thereby effectively improving the maintainability of the auxiliary mounting joint 34. Under the premise of fully considering the economic efficiency, the connection and centering design of the hot end outer casing 1, the diffuser casing 33 and the auxiliary mounting joint 34 is carried out to improve the accuracy of the connection and assembly of the three.

[0023] Furthermore, if Figure 2As shown, the annular surface wall thickness δ1 of the front mounting edge of the casing front mounting section 11 near its front mounting edge is 1.5mm to 3mm, ensuring sufficient strength and preventing deformation of the annular surface, while also achieving a lightweight design for the hot end outer casing 1. The outer edge surfaces of the rear mounting edge of the diffuser casing 33 and the front mounting edge of the casing front mounting section 11 have equal outer diameters, and the distance L1 between the outer edges of the two surfaces and the center of the fastening bolts 35 is 6mm to 9mm. This prevents the front mounting edge of the casing front mounting section 11 from being torn by the auxiliary mounting section 34 and fastening bolts 35 when the engine is subjected to excessive external forces.

[0024] Alternatively, as Figure 3 As shown, the inner profile of the power turbine section 13 is an axially stepped surface, which facilitates gas flow. Furthermore, considering both engine weight and cost, the distance L2 between the rear exhaust edge 131 of the power turbine section 13 and the end of the power turbine should be as large as possible to increase the distance between the power turbine and the weak rear exhaust edge 131, thereby ensuring adequate containment of the power turbine blades 52. Furthermore, considering economic efficiency, the annular wall thickness δ2 of the power turbine section 13 corresponding to the power turbine position is set at 5 mm to 8 mm in the present invention, and the distance L2 between the rear exhaust edge 131 of the power turbine section 13 and the axial end of the power turbine is set at 10 mm to 15 mm.

[0025] Alternatively, as Figure 1 and Figure 5 As shown, the hot end outer casing 1 also houses a flame tube head connecting the flame tube inner ring 41 and the flame tube outer ring 42. The flame tube head is also connected to a nozzle. A nozzle mounting section 121 for mounting the nozzle is vertically positioned on the casing head 12. The nozzle is secured to the nozzle mounting section 121 via setscrews, which are also equipped with wire screws to prevent rotation. In this alternative solution, the hot end outer casing 1 is subject to significant axial forces, so the nozzle is secured with setscrews. To eliminate the need for fuses and improve engine maintainability and repairability, the setscrews are also secured with wire screws to prevent loosening.

[0026] Preferably, if Figure 6 and Figure 7 As shown, since the nozzle mounting section 121 is arranged vertically, it bears a large axial force and is easy to deform. Therefore, in this preferred solution, the wall of the nozzle mounting section 121 where the nozzle is installed is locally thickened, that is, Figure 7 The nozzle mounting hole 122 is locally thickened so that the local wall thickness δ3 after the thickening design is 7 to 9 mm. Furthermore, in order to achieve the installation of the wire screw sleeve and combine it with weight control, the nozzle mounting section 121 of the casing head is designed with a non-uniform wall thickness structure. On the basis of the local thickening design at the fastening screw installation position, the wall surface of the nozzle mounting section 121 for the fastening screw to pass through and install is also locally thickened, that is, for example Figure 7The position of the middle bolt mounting hole 123 is locally thickened so that the thickness δ4 of the local wall after the thickening design is 11 to 13 mm.

[0027] Alternatively, as Figure 1 and Figure 5 As shown, the outer ring 42 of the flame tube is also fixed to the front mounting section 11 of the casing by a plurality of fixing pins 17 evenly distributed in the circumferential direction. The various mounting seats include two nozzle mounting seats 18 and two nozzle seats 19. The two nozzle mounting seats 18 are fixed on the outer wall surface of the front mounting section 11 of the casing at intervals in the circumferential direction, and the two nozzle seats 19 are fixed on the outer wall surface of the outer ring 42 of the flame tube at intervals in the circumferential direction, and the two nozzle seats 19 are arranged corresponding to the two nozzle mounting seats 18. An ignition nozzle 61 is provided in each nozzle mounting seat 18, and the bottom end of the ignition nozzle 61 is inserted into the corresponding nozzle seat 19. In this optional scheme, the combustion chamber is ignited by means of two ignition nozzles 61 inserted into the interior of the flame tube, and the ignition nozzle 61 is mounted on the nozzle mounting seat 18 and the corresponding nozzle seat 19 of the hot end outer casing 1; in this optional scheme, as Figure 4 As shown, the hot end outer casing 1 is designed with 6 evenly distributed fixing pin mounting seats, which are equipped with 6 evenly distributed fixing pins 17 to support and fix the flame tube.

[0028] Preferably, if Figure 5 As shown, the centers of the two ignition nozzles 61 coincide with the centers of the main combustion holes on the outer ring 42 of the flame tube. The first ignition nozzle 61 is located directly above the engine, and the projection of the first ignition nozzle 61 in the vertical plane perpendicular to the axis is located between the projections of the two adjacent mounting pins in the vertical plane. The second ignition nozzle 61 is located to one side directly below the engine. In this preferred embodiment, one ignition nozzle 61 is arranged directly above the engine, and the ignition nozzle 61 installed there will not be soaked in oil, which can avoid the failure of ignition caused by the ignition nozzle 61 being soaked in oil, thereby improving the reliability of ignition and combustion; the other ignition nozzle 61 is arranged 20° to the left of the engine directly below (when viewed in the reverse direction, as shown in FIG. 1 ). Figure 4 As shown in the figure), it is not arranged directly under the engine. Firstly, it prevents the misfire problem caused by oil accumulation on the surface of the ignition nozzle 61; secondly, it realizes the error-proof property of the flame tube, ensures the performance of the combustion chamber components after installation, and avoids the deterioration of the combustion chamber outlet temperature field caused by the angular position error of the fuel nozzle; thirdly, it is affected by the gravity of the fuel, which can ensure excellent combustion chamber ignition performance. At 4.5km and -40℃, ignition can be successful without the help of a fuel heating device.

[0029] Alternatively, as Figure 1As shown, the first ends of both the inner casing 31 and the gas turbine casing 32 are circumferentially secured to the casing head 12 with multiple sets of fastening bolts 35 and flared, self-locking nuts to prevent the screws from rotating. The second ends of both the inner casing 31 and the gas turbine casing 32 extend toward the free end of the liner inner ring 41. The second end of the inner casing 31 is overlapped and connected to the free end of the liner inner ring 41 via an overlapping edge 311. This simplifies the structure while ensuring that the total pressure loss in the combustion chamber is not excessively reduced.

[0030] According to another aspect of the present invention, a turbine engine is also provided, having a turboshaft engine containment hot end casing as described above. In the turbine engine of the present invention, the hot end outer casing 1 is an integrated design, and the selection of welding position and welding method, the selection of the distance between the center of the connecting bolt hole on the front mounting edge of the hot end outer casing 1 and the maximum outer circle of the front mounting edge, the power turbine containment design, the selection of the circumferential position of the nozzle mounting seat 18, and the structural design of the nozzle mounting section 121 of the casing head 12 of the hot end outer casing 1 are focused on. Problems such as weld cracks, insufficient strength, and non-containment of power turbine blades are solved. At the same time, the error-proofing design of the flame tube is taken into consideration, the circumferential position of the nozzle mounting seat 18 is reasonably selected, and the integrated hot end outer casing is locally thickened, taking into account strength, containment, weight, and economy.

[0031] The engine of the present invention has been evaluated by over-temperature, endurance and high-altitude platform airworthiness tests. It can be successfully ignited at 4.5km and -40℃ without the aid of a fuel heating device. A 3000-hour acceleration spectrum equivalent test has been completed on two complete machines. At the same time, it has passed the complete machine inclusive airworthiness test and the integrated hot end outer casing pressure airworthiness test. No deformation, cracks or damage to the front mounting edge have occurred. The structure is reliable and the service life is long. On the basis of ensuring the service life, maintainability and repairability, the economy is fully considered to obtain an integrated casing with long service life, high maintainability, good economy and inclusiveness. At the same time, it is guaranteed that the adapted combustion chamber can be successfully ignited without the aid of a fuel heating device under high-altitude and cold conditions.

[0032] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A turboshaft engine inclusive hot end casing, characterized in that: include: A hot end outer casing (1), an inner casing (31) and a gas turbine casing (32) of a full-ring structure; The hot end outer casing (1) includes a casing front mounting section (11), a casing head (12) and a power turbine section (13) arranged in sequence along the axial direction. The casing front mounting section (11), the casing head (12) and the power turbine section (13) are designed as an integrated whole. The three are welded together by two circumferential electron beam ring welding (14) arranged in sequence to form an integrated hot end outer casing (1). The hot end outer casing (1) is also connected to a combustion chamber peephole seat (15), a turbine peephole seat (16) and a plurality of mounting seats by electron beam welding. The gas turbine casing (32) and the inner casing (31) are arranged in an inner and outer manner and connected to the hot end outer casing (1), and the gas turbine casing (32), the inner casing (31), the flame tube inner ring (41) and the flame tube outer ring (42) connected to the hot end outer casing (1) and arranged in an inner and outer manner, and the hot end outer casing (1) cooperate to form a multi-layer wall surface arranged in sequence from the inside to the outside to accommodate the gas turbine blades (51); The power turbine section (13) is also designed to contain the power turbine blades (52).

2. The turboshaft engine inclusive hot end casing according to claim 1, characterized in that: The diffuser casing (33) is arranged axially upstream of the casing front mounting section (11), the auxiliary mounting section (34) is sleeved outside the casing front mounting section (11), and the rear mounting edge of the diffuser casing (33), the front mounting edge of the casing front mounting section (11) and the auxiliary mounting section (34) are connected and locked by a fastening bolt (35) passing through the three and a self-locking nut (36) sleeved on the outer circle of the fastening bolt (35).

3. The turboshaft engine inclusive hot end casing according to claim 2, characterized in that: The annular wall thickness δ1 of the front mounting section (11) of the casing near its front mounting edge is 1.5 mm to 3 mm; the outer diameters of the outer edges of the rear mounting edge of the diffuser casing (33) and the front mounting edge of the casing front mounting section (11) are equal, and the distance L1 between the outer edges of the two and the center of the fastening bolt (35) is 6 mm to 9 mm.

4. The turboshaft engine inclusive hot end casing according to claim 1, characterized in that: The inner profile of the power turbine section (13) is a stepped surface arranged along the axial direction; the wall thickness δ2 of the power turbine section (13) corresponding to the power turbine is 5 mm to 8 mm; and the spacing L2 between the rear exhaust edge (131) of the power turbine section (13) and the axial end of the power turbine is 10 mm to 15 mm.

5. The turboshaft engine inclusive hot end casing according to claim 1, characterized in that: A flame tube head connected to the flame tube inner ring (41) and the flame tube outer ring (42) is also provided in the hot end outer casing (1), and a nozzle is also connected to the flame tube head; a nozzle mounting section (121) for mounting the nozzle is vertically arranged on the casing head (12), and the nozzle is fixed to the nozzle mounting section (121) by a fastening screw, and a wire screw sleeve is also provided on the fastening screw to prevent rotation.

6. The turboshaft engine inclusive hot end casing according to claim 5, characterized in that: The nozzle installation section (121) is provided with a local wall thickening design at a location where the nozzle is inserted and installed, so that the local wall thickness δ3 after the thickening design is 7 to 9 mm; the nozzle installation section (121) is provided with a local wall thickening design at a location where the fastening screw is inserted and installed, so that the local wall thickness δ4 after the thickening design is 11 to 13 mm.

7. The turboshaft engine inclusive hot end casing according to claim 1, characterized in that: The flame tube outer ring (42) is also fixed to the front mounting section (11) of the casing by a plurality of fixing pins (17) uniformly distributed in the circumferential direction; the multiple mounting seats include two nozzle mounting seats (18) and two nozzle seats (19), the two nozzle mounting seats (18) are fixed on the outer wall surface of the front mounting section (11) of the casing at intervals along the circumferential direction, and the two nozzle seats (19) are fixed on the outer wall surface of the flame tube outer ring (42) at intervals along the circumferential direction, and the two nozzle seats (19) are arranged corresponding to the two nozzle mounting seats (18); each nozzle mounting seat (18) is provided with an ignition nozzle (61), and the bottom end of the ignition nozzle (61) is inserted into the corresponding nozzle seat (19).

8. The turboshaft engine inclusive hot end casing according to claim 7, characterized in that: The centers of the two ignition nozzles (61) respectively coincide with the centers of the main combustion holes on the outer ring (42) of the flame tube; The first ignition nozzle (61) is located directly above the engine, and the projection of the first ignition nozzle (61) in a vertical plane perpendicular to the axis is located between the projections of two adjacent mounting pins in the vertical plane; the second ignition nozzle (61) is located directly below the engine and slightly to one side.

9. The turboshaft engine inclusive hot end casing according to claim 1, characterized in that: The first ends of the inner casing (31) and the gas turbine casing (32) are circumferentially locked and fixed with flared self-locking nuts in the casing head (12) by multiple sets of fastening bolts (35); the second ends of the inner casing (31) and the gas turbine casing (32) extend toward the free end of the flame tube inner ring (41), and the second end of the inner casing (31) is overlapped and connected with the free end of the flame tube inner ring (41) through an overlap edge (311).

10. A turbine engine, characterized in that: A turboshaft engine containing hot end casing according to any one of claims 1 to 9.

Images