High-temperature high-pressure floating air entraining seal structure

Abstract

The application discloses a high-temperature and high-pressure floating air-seal structure and belongs to the technical field of an aero-engine air system. The structure comprises a combustion chamber case, an outer-duct case, an adapter pipe and a seat bend pipe. The combustion chamber case is provided with an air-seal floating mechanism. The outer-duct case is provided with an air extraction mounting seat. One end of the adapter pipe is in gap cooperation with the air-seal floating mechanism and is communicated with the inside of the combustion chamber through the air-seal floating mechanism. The other end of the adapter pipe and one end of the seat bend pipe are fixed to the air extraction mounting seat through a plurality of connecting components. The end of the adapter pipe, which is away from the combustion chamber case, is communicated with the outside through the seat bend pipe. The air-seal floating mechanism is sealed by utilizing the air pressure difference between the inside and outside of the combustion chamber cavity and the cooperation between the components. The sealing performance is good, the service life is prolonged, the structure of the adapter pipe is simplified, and the manufacturing cost is reduced. The adapter pipe is not fixed to the combustion chamber case, so that the influence of the vibration stress on the adapter pipe is reduced.

Description

Technical Field

[0001] This invention relates to a high-temperature and high-pressure floating bleed air sealing structure, belonging to the technical field of aero-engine air system. Background Technology

[0002] The bleed air duct is an important component of the air system of an aero-engine. It connects the combustion chamber and the outer bypass casing, safely drawing the high-temperature, high-pressure hot airflow from the combustion chamber to the outside of the engine. It then connects with other ducts to transport the hot air, ultimately serving two purposes on the engine: supporting the pressurization of the front chamber and preventing icing at the engine inlet.

[0003] Currently, the high-temperature, high-pressure airflow inside aero engines is typically extracted directly using an integrated duct and sealed with rubber rings or expansion rings. Existing aero engine casings often use high-strength high-temperature alloys for the inner casing and lighter aluminum alloys for the outer casing. The two materials have significantly different coefficients of linear expansion, and the temperature difference between the inner and outer casings is also large, resulting in significant relative displacement of the mounting holes on the inner and outer casings under hot conditions. The integrated duct has limited mobility, making it prone to squeezing and rubbing against the casing wall, generating internal stress and greatly reducing its service life. In severe cases, this can threaten engine safety. Furthermore, the integrated duct requires precise positioning of the mounting holes, making it susceptible to scratches and collisions during installation, resulting in poor assemblability and maintainability.

[0004] To address this, Chinese patent document CN116518159A discloses a pipeline lead-out structure, a casing, and an aero-engine. The pipeline lead-out structure includes a lead-out sleeve for connecting the interior and exterior of the casing and a mounting base for mounting on the outer casing. A stepped hole is formed through the mounting base along the height direction. A floating ring is fitted with the small-diameter hole of the stepped hole with clearance. A first frustum protrudes radially from the outer side of the floating ring's upper end along the height direction, fitting with the large-diameter hole of the stepped hole with clearance. A cover plate is provided on the mounting base to restrict the movement of the floating ring along the height direction. One end of the lead-out sleeve is located on the inner casing, and the other end is fitted with the inner hole of the floating ring with clearance, extending to the outside of the outer casing for external pipeline connection. A first sealing ring is provided between the lead-out sleeve and the inner hole of the floating ring. This invention achieves installation compensation and compensation for the radial offset of the lead-out sleeve due to thermal expansion between the inner and outer casings, reducing the positional accuracy requirements of the lead-out sleeve's mounting hole.

[0005] However, the pipeline outlet structure uses a first sealing ring and a second sealing ring, but the sealing effect and service life of the sealing ring may not be ideal in high-temperature environments; multiple grooves need to be machined circumferentially on the outlet sleeve, as well as the first annular groove for installing the first sealing ring, which is relatively complicated to manufacture; in addition, one end of the outlet sleeve is fixed to the inner casing with large vibration, which causes the outlet sleeve to still generate large vibration stress during actual use. Summary of the Invention

[0006] To solve the above-mentioned technical problems, the present invention provides a high-temperature and high-pressure floating air-sealing structure.

[0007] This invention is achieved through the following technical solution:

[0008] A high-temperature, high-pressure floating bleed air sealing structure includes a combustion chamber casing, an outer bypass casing, a transfer pipe, and a seated bend. The combustion chamber casing is equipped with a gas-tight floating mechanism, and the outer bypass casing is equipped with a bleed air mounting seat. One end of the transfer pipe is clearance-fitted with the gas-tight floating mechanism and communicates with the interior of the combustion chamber through the gas-tight floating mechanism. The other end of the transfer pipe and one end of the seated bend are together installed and fixed to the bleed air mounting seat through multiple connecting components, and the end of the transfer pipe away from the combustion chamber casing communicates with the outside through the seated bend.

[0009] The gas-tight floating mechanism includes a cabin bleed air mounting base and a bushing assembly with a displacement ring. The cabin bleed air mounting base is located on the combustion chamber casing, and the bushing assembly with the displacement ring is detachably connected to the cabin bleed air mounting base.

[0010] The cabin bleed air mounting base is provided with a secondary cylindrical hole, which includes a primary hole and a secondary hole arranged coaxially. The diameter of the primary hole is smaller than that of the secondary hole, and the secondary hole is provided with internal threads. The cabin bleed air mounting base includes an arc-shaped base plate and a seat body provided on the arc-shaped base plate.

[0011] The bushing assembly with displacement ring includes a special nut, a displacement ring, and a plug. The plug is located inside the special nut and is fixedly connected to the special nut, thus confining the displacement ring within the special nut. The displacement ring can float along the axial and radial directions of the special nut.

[0012] The special nut is coaxially provided with a three-stage cylindrical hole, which includes a first-stage nut hole, a second-stage nut hole, and a third-stage nut hole arranged in sequence with increasing diameters. The special nut has an external thread on the outer circular surface at the first-stage nut hole. The special nut has an annular surface below the second-stage nut hole that fits 100% with the top surface of the cabin bleed air mounting base. The outer circle of the special nut has an annular platform, and multiple grooves are formed in a circular array on the annular platform.

[0013] The displacement ring is provided with a through hole on the same axis. The displacement ring includes a large annular platform and a small annular platform. The small annular platform is connected to the large annular platform through a cylindrical section, and the small annular platform, the cylindrical section and the large annular platform together form a flanged groove.

[0014] The plug includes a cylinder and a ring inside the cylinder. The lower end face of the ring is coplanar with the lower end face of the cylinder. The cylinder is clearance-fitted with the three-stage hole of the nut on the special nut. The upper end face of the cylinder is coplanar with the upper end face of the three-stage hole of the nut and is sealed by welding. The upper end of the inner hole of the ring extends upward along the axial direction to form an annular flange groove with the cylinder. The lower end of the inner hole of the ring extends downward along the axial direction to form an annular contact surface with a fit of not less than 80% with the top surface of the large annular platform.

[0015] The combustion chamber casing is provided with lugs, and a locking hole is provided on the annular platform. The locking hole is connected to the lugs by a steel wire to prevent the special nut from loosening.

[0016] The connecting pipe includes a thick-walled section and a thin-walled section. One end of the thin-walled section is coaxially connected to one end of the thick-walled section, and the inner diameter of the thin-walled section is the same as that of the thick-walled section. A pipe butterfly platform is provided on the end of the thick-walled section away from the thin-walled section, and multiple bolt holes are provided on the pipe butterfly platform.

[0017] A chamfer R is provided at the junction of the outer circle of the thin-walled section and the outer circle of the thick-walled section;

[0018] The thin-walled section is fitted with a clearance fit to the through hole on the displacement ring.

[0019] The air extraction mounting base includes an arc plate and a butterfly-shaped platform on the arc plate. The arc plate has multiple rivet holes, and the butterfly-shaped platform has multiple threaded holes. The arc plate and the butterfly-shaped platform together have a through hole.

[0020] The seated bend includes a bend seat and a bend provided on the bend seat. The bend and the bend seat are provided with an airflow channel. The bend seat is provided with multiple screw holes.

[0021] A conduit is connected to the end of the bend that is away from the bend seat.

[0022] The connecting assembly includes a bolt and a locking plate fitted onto the bolt.

[0023] The beneficial effects of this invention are as follows:

[0024] 1. By utilizing the fact that the gas pressure inside the combustion chamber is greater than the gas pressure inside the outer bypass channel and is also greater than the external gas pressure, the high-temperature and high-pressure gas inside the combustion chamber is led out to the outside of the outer bypass casing through the transfer pipe and the seated elbow, thus realizing the bleed gas.

[0025] 2. By utilizing the pressure difference between the inside and outside of the combustion chamber and the cooperation between the various components in the floating bleed air sealing structure, a seal is achieved without the need for sealing elements. This eliminates the need for sealing rings in existing technologies, ensuring that the floating bleed air sealing structure has good sealing performance in high-temperature environments and extending its service life. At the same time, it helps to simplify the structure of the transfer pipe and reduce its manufacturing cost.

[0026] 3. Since the transfer pipe is not fixed to the combustion chamber casing, most of the vibration from the engine body is effectively cut off, so that only a small part of the vibration of the whole engine is transmitted to the transfer pipe, which significantly reduces the impact of vibration stress on the transfer pipe.

[0027] 4. The present invention can achieve a guiding function: a chamfer R is provided at the junction of the outer circle of the thin-walled section and the outer circle of the thick-walled section on the transfer pipe. When gas leaks from the combustion chamber, the chamfer R can guide the high-temperature gas to flow backward with the outer duct flow, so as to protect the composite outer duct casing.

[0028] 5. This invention can achieve a two-line defense function: After the special nut is threadedly connected to the cabin bleed air mounting seat fixed on the combustion chamber casing, the annular surface of the special nut fits against the top surface of the cabin bleed air mounting seat to achieve a seal, preventing high-temperature gas from leaking out from here, which is the first line of sealing defense; When the engine is running, there is combustion chamber airflow from front to back in the combustion chamber cavity, and there is also bypass airflow from front to back in the bypass duct. Since the air pressure in the combustion chamber cavity is greater than the air pressure in the bypass duct and greater than the air pressure in the duct, an automatic bleed air function can be achieved. At this time, the displacement ring moves in the positive direction of the Z-axis under the action of air pressure. The top surface of the large annular platform of the displacement ring fits against the annular contact surface of the bottom of the plug ring, which plays a sealing role against the high-temperature and high-pressure airflow, which is the second line of sealing defense.

[0029] 6. This invention can achieve three compensation functions: First, the lower end of the transfer pipe is clearance-fitted with the displacement ring, so that the lower end of the transfer pipe is not absolutely constrained. When the transfer pipe is subjected to high temperature and high pressure gas and undergoes thermal expansion, it can freely contract in the Z direction, reducing structural stress, which is stress compensation; Second, since the displacement ring is relatively free in all directions in space, that is, the displacement ring can move along its own radial and axial directions in a limited space, the machining deviation of the air extraction mounting seat and the cabin bleed air mounting seat can be ignored within a small range, and the transfer pipe can be compensated for displacement in all directions in space; Third, since the transfer pipe is not fixed to the combustion chamber casing, most of the vibration from the engine body is effectively cut off, so that only a small part of the vibration of the whole machine is transmitted to the transfer pipe, reducing the impact of the vibration of the whole machine, which is vibration compensation. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of the present invention;

[0031] Figure 2 This is a schematic diagram of the cockpit bleed air mounting base of the present invention;

[0032] Figure 3 This is a cross-sectional view of the cockpit bleed air mounting base of the present invention;

[0033] Figure 4 This is a schematic diagram of the structure of the displacement ring bushing assembly of the present invention;

[0034] Figure 5 This is a cross-sectional view of the displacement ring bushing assembly of the present invention;

[0035] Figure 6 for Figure 5 A magnified view of a portion at point A;

[0036] Figure 7 for Figure 6 Enlarged view of the area after the gap transfer;

[0037] Figure 8 This is an assembly diagram of the plug and special nut of the present invention;

[0038] Figure 9 This is a top view of the special nut of the present invention;

[0039] Figure 10 This is a cross-sectional view of the special nut of the present invention;

[0040] Figure 11 This is a schematic diagram of the plug structure of the present invention;

[0041] Figure 12 This is a cross-sectional view of the plug of the present invention;

[0042] Figure 13 This is a schematic diagram of the displacement ring structure of the present invention;

[0043] Figure 14 This is a cross-sectional view of the displacement ring of the present invention;

[0044] Figure 15 This is a schematic diagram of the transfer tube structure of the present invention;

[0045] Figure 16 This is a cross-sectional view of the adapter pipe of the present invention;

[0046] Figure 17 This is a schematic diagram of the structure of the vacuum mounting base of the present invention;

[0047] Figure 18 This is a cross-sectional view of the vacuum mounting base of the present invention;

[0048] Figure 19 This is a schematic diagram of the structure of the seated bend of the present invention;

[0049] Figure 20 This is a partial cross-sectional view of the seated bend of the present invention.

[0050] In the diagram: 1-Conduit, 2-Bend with seat, 3-Bolt, 4-Annular contact surface, 5-Ejection mounting base, 6-Outer bypass casing, 7-Transfer pipe, 8-Plug, 9-Displacement ring, 10-Special nut, 11-Combustion chamber casing, 12-Cockpit bleed air mounting base, 13-Ear plate;

[0051] A1 - Top surface of the ring-shaped platform, A2 - Special process surface, A3 - Circular surface, A4 - Circular contact surface, A5 - Circular ring, A6 - Cylinder, A7 - Outer cylindrical surface;

[0052] D1 - Primary hole, D2 - Secondary hole, D3 - Through hole, D4 ​​- Primary nut hole, D5 - Secondary nut hole, D6 - Tertiary nut hole, D7 - Locking hole, D8 - Gas outlet channel, D9 - Bolt hole, D10 - Through hole, D11 - Threaded hole, D12 - Rivet hole, D13 - Airflow channel, D14 - Screw hole;

[0053] e1 - Internal thread, e2 - External thread;

[0054] G1-Circular arc base plate, G2-Small annular stage, G3-Large annular stage, G4-Annular stage, G5-Tube butterfly stage, G6-Butterfly stage seat, G7-Circular arc plate, G8-Bent pipe seat, g1-Flanged groove, g2-Groove, g3-Annular flanged groove.

[0055] H1 - Annular cavity;

[0056] K1 - outer bypass channel, K2 - cavity, K3 - L-shaped cavity, K6 - combustion chamber cavity;

[0057] L2 - Thick-walled section, L3 - Thin-walled section. Detailed Implementation

[0058] The technical solution of the present invention is further described below, but the scope of protection is not limited to what is described.

[0059] like Figures 1 to 20As shown, the high-temperature and high-pressure floating bleed-out gas sealing structure of the present invention includes a combustion chamber housing 11, an outer bypass housing 6, a transfer pipe 7, and a seated bend 2. The combustion chamber housing 11 is equipped with a gas-tight floating mechanism, and the outer bypass housing 6 is equipped with a suction mounting seat 5. One end of the transfer pipe 7 is clearance-fitted with the gas-tight floating mechanism and communicates with the interior of the combustion chamber through the gas-tight floating mechanism. The other end of the transfer pipe 7 and one end of the seated bend 2 are together installed and fixed to the suction mounting seat 5 through multiple connecting components. The end of the transfer pipe 7 away from the combustion chamber housing 11 communicates with the outside through the seated bend 2. In use, taking advantage of the fact that the gas pressure inside the combustion chamber cavity K6 is greater than the gas pressure inside the outer bypass channel K1 and greater than the external gas pressure, the high-temperature and high-pressure gas inside the combustion chamber cavity K6 is drawn out to the outside of the outer bypass housing 6 through the transfer pipe 7 and the seated bend 2, thus achieving bleed-out gas. By utilizing the pressure difference between the inside and outside of the combustion chamber cavity K6 and the cooperation between the components in the floating bleed air sealing structure, sealing is achieved without the need for seals, eliminating the need for sealing rings in existing technologies. This ensures that the floating bleed air sealing structure has good sealing performance in high-temperature environments and extends its service life. It also helps simplify the structure of the adapter pipe 7 and reduce its manufacturing cost. One end of the adapter pipe 7 is clearance-fitted with the gas-tight floating mechanism mounted on the combustion chamber casing 11 to achieve omnidirectional floating functionality. Because the adapter pipe 7 is not fixedly connected to the combustion chamber casing 11, most of the vibration from the engine body is effectively cut off, so that only a small portion of the overall engine vibration is transmitted to the adapter pipe 7, significantly reducing the impact of vibration stress on the adapter pipe 7.

[0060] The gas-tight floating mechanism includes a cabin bleed air mounting base 12 and a bushing assembly with a displacement ring. The cabin bleed air mounting base 12 is mounted on the combustion chamber casing 11, and the bushing assembly with the displacement ring is detachably connected to the cabin bleed air mounting base 12. In use, the cabin bleed air mounting base 12 is welded to the combustion chamber casing 11.

[0061] The cabin bleed air mounting base 12 has a secondary cylindrical hole, which includes a primary hole D1 and a secondary hole D2 arranged coaxially. The diameter of the primary hole D1 is smaller than the diameter of the secondary hole D2, and the secondary hole D2 has an internal thread e1. The cabin bleed air mounting base 12 includes an arc-shaped base plate G1 and a seat body disposed on the arc-shaped base plate G1. In use, the internal thread e1 on the secondary hole D2 is used to threadly connect with the external thread e2 on the special nut 10, so as to assemble the special nut 10 with the cabin bleed air mounting base 12.

[0062] The bushing assembly with displacement ring includes a special nut 10, a displacement ring 9, and a plug 8. The plug 8 is located inside the special nut 10 and is fixedly connected to the special nut 10, and restricts the displacement ring 9 inside the special nut 10. The displacement ring 9 can float along the axial and radial directions of the special nut 10.

[0063] The special nut 10 is coaxially provided with a three-stage cylindrical hole, which includes a first-stage nut hole D4, a second-stage nut hole D5, and a third-stage nut hole D6 arranged coaxially and sequentially with increasing diameters. The special nut 10 has an external thread e2 on the outer circular surface at the first-stage nut hole D4. The special nut 10 has an annular surface A3 below the second-stage nut hole D5, which has a 100% fit with the top surface of the cabin bleed air mounting base 12. The special nut 10 has an annular platform G4 on its outer circle, and the annular platform G4 has multiple grooves g2 arranged in a circular array.

[0064] The displacement ring 9 is provided with a through hole D3 on the same axis. The displacement ring 9 includes a large annular platform G3 and a small annular platform G2. The small annular platform G2 is connected to the large annular platform G3 through a cylindrical section. The small annular platform G2, the cylindrical section and the large annular platform G3 together form a flanged groove g1.

[0065] The plug 8 includes a cylinder A6 and a ring A5 disposed inside the cylinder A6. The lower end face of the ring A5 is coplanar with the lower end face of the cylinder A6. The cylinder A6 is clearance-fitted with the nut three-stage hole D6 on the special nut 10. The upper end face of the cylinder A6 is coplanar with the upper end face of the nut three-stage hole D6 and is sealed and welded. The upper end of the inner hole of the ring A5 extends upward along the axial direction to form an annular flange groove g3 with the cylinder A6. The lower end of the inner hole of the ring A5 extends downward along the axial direction to form an annular contact surface A4 with a fitting degree of not less than 80% with the top surface A1 of the large annular platform G3.

[0066] like Figure 8 As shown, during use, after the upper end face of cylinder A6 is coplanar with the upper end face of the nut's third-stage hole D6 and sealed by welding, an annular cavity H1 of unequal height is formed between the bottom surface of ring A5 and the upper end face of the nut's first-stage hole D4. The large annular platform G3 on displacement ring 9 is assembled in this annular cavity H1, and a cavity K2 is formed between the flanged groove g1 on displacement ring 9 and the inner wall of the ring A5. It is ensured that the height of the large annular platform G3 is less than the minimum height of the annular cavity H1, and that the outer diameter of the large annular platform G3 is less than the diameter of the nut's second-stage hole D5 on the special nut 10, to form... Figure 5 and Figure 6 The inverted L-shaped cavity K3 shown is a variable cavity that can be transformed into, for example, the L-shaped cavity K3. Figure 7 The L-shaped cavity shown. Figure 5 and Figure 6 As shown, when the aero-engine is not operating, there is a gap between the top surface A1 of the displacement ring 9 and the annular contact surface A4 of the plug 8, and the cavity K2 and the L-shaped cavity K3 are two connected cavities; as Figure 7As shown, when the aero-engine is operating, the top surface A1 of the annular platform on the displacement ring 9 is in contact with the annular contact surface A4 on the plug 8, and the gap shifts to the area between the bottom surface of the large annular platform G3 and the upper end surface of the first-stage hole D4 on the special nut 10. At this time, the cavity K2 and the L-shaped cavity K3 are separated by the displacement ring 9 and are two independent cavities. Due to the presence of the cavity K2 and the L-shaped cavity K3, the displacement ring 9 can move radially and axially within a limited space and can also be flipped within a limited space. A special process surface A2 is provided on the wall of the through hole D3 on the displacement ring 9 (for example, a wear-resistant coating is plated on the wall of the through hole D3 to form a special process surface A2) to prevent the displacement ring 9 from rubbing against the adapter pipe 7. Multiple grooves g2 are formed in a circular array on the annular platform G4 to reduce the impact of airflow on the special nut 10 and reduce the stress on the entire structure. After the special nut 10 is installed on the cabin bleed air mounting base 12, the annular surface A3 on the special nut 10 fits against the top surface of the cabin bleed air mounting base 12, forming a gas sealing barrier.

[0067] The combustion chamber casing 11 is provided with lugs 13, and the annular platform G4 is provided with locking holes D7. The locking holes D7 are connected to the lugs 13 by steel wire to prevent the special nut 10 from loosening.

[0068] The transfer pipe 7 includes a thick-walled section L2 and a thin-walled section L3. One end of the thin-walled section L3 is coaxially connected to one end of the thick-walled section L2, and the inner diameter of the thin-walled section L3 is the same as the inner diameter of the thick-walled section L2. A pipe butterfly platform G5 is provided on the end of the thick-walled section L2 away from the thin-walled section L3, and multiple bolt holes D9 are provided on the pipe butterfly platform G5.

[0069] A chamfer R is provided at the junction of the outer circle of the thin-walled section L3 and the outer circle of the thick-walled section L2;

[0070] The thin-walled section L3 is clearance-fitted with the through hole D3 on the displacement ring 9.

[0071] During use, the inner hole of the transfer pipe 7 serves as the gas outlet channel D8. A chamfer R is provided at the transition between the outer circle of the thin-walled section L3 and the outer circle of the thick-walled section L2 to facilitate a smooth transition in the wall thickness of the transfer pipe 7. The chamfer R also alters the flow direction of high-temperature gas leaking from the clearance between the displacement ring 9 and the transfer pipe 7 in the combustion chamber, thus protecting the composite outer casing 6. The outer cylindrical surface A7 of the thin-walled section L3 undergoes special treatment (e.g., a wear-resistant coating) to prevent friction with the wall of the through hole D3 on the displacement ring 9. Figure 1As shown, one end of the adapter pipe 7 is equipped with a pipe butterfly platform G5. The pipe butterfly platform G5 is fixed between the seated elbow 2 and the air extraction mounting base 5 by bolts 3. The end of the adapter pipe 7 away from the pipe butterfly platform G5 is clearance-fitted with the displacement ring 9. The displacement ring 9 is restricted within the special nut 10 by the plug 8. The displacement ring 9 can move in the X positive and negative directions, Y positive and negative directions, and Z positive and negative directions in a limited space. The movable distance is different in each direction, and engine pipeline displacement compensation can be achieved in each direction. The displacement ring 9 can also rotate around the X, Y, and Z axes in a limited space. At the same time, since the end of the adapter pipe 7 away from the pipe butterfly platform G5 is not constrained, it can also achieve its own thermal expansion compensation, that is, achieve dual displacement compensation in this direction.

[0072] The air extraction mounting base 5 includes an arc plate G7 and a butterfly-shaped platform G6 mounted on the arc plate G7. The arc plate G7 has multiple rivet holes D12, and the butterfly-shaped platform G6 has multiple threaded holes D11. The arc plate G7 and the butterfly-shaped platform G6 share a through hole D10. In use, the through hole D10 serves as the installation channel for the adapter pipe 7.

[0073] The bent pipe 2 with a seat includes a bent pipe seat G8 and a bent pipe provided on the bent pipe seat G8. The bent pipe and the bent pipe seat G8 are provided with an airflow channel D13. The bent pipe seat G8 is provided with a plurality of screw holes D14.

[0074] A conduit 1 is connected to the end of the bend away from the bend seat G8.

[0075] The connecting assembly includes a bolt 3 and a locking plate 4 fitted onto the bolt 3. After the locking plate 4 is fitted onto the bolt 3, one end of the bolt 3 passes through the screw hole D14 on the seated elbow 2 and the bolt hole D9 on the adapter pipe 7 in sequence, and then is threadedly connected and tightened with the threaded hole D11 on the vacuum mounting base 5, thereby installing and fixing one end of the seated elbow 2 and the adapter pipe 7 onto the vacuum mounting base 5, and then using the locking plate 4 to prevent the bolt 3 from loosening.

[0076] Specifically, the high-temperature and high-pressure floating air-sealing structure described in this invention can achieve one guiding function, two protective lines, and three compensation functions.

[0077] One guide is provided: a chamfer R is provided at the junction of the outer circle of the thin-walled section L3 and the outer circle of the thick-walled section L2 on the transfer pipe 7. When gas leaks from the combustion chamber, the chamfer R can guide the high-temperature gas to flow backward with the outer duct airflow, so as to protect the composite outer duct casing 6.

[0078] The two lines of defense are as follows: After the special nut 10 is threadedly connected to the cockpit bleed air mounting bracket 12 fixed on the combustion chamber casing 11, the annular surface A3 on the special nut 10 fits against the top surface of the cockpit bleed air mounting bracket 12 to achieve a seal, preventing high-temperature gas from leaking out from here, which is the first line of sealing defense; such as Figure 1As shown, when the engine is running, there is a front-to-back combustion chamber airflow in the combustion chamber cavity K6 and a front-to-back bypass airflow in the bypass channel K1. Since the air pressure in the combustion chamber cavity K6 is greater than the air pressure in the bypass channel K1 and greater than the air pressure in the duct 1, the automatic air bleed function can be realized. At this time, the displacement ring 9 moves in the positive direction of the Z-axis under the action of air pressure. The top surface A1 of the large annular platform G3 of the displacement ring 9 fits against the annular contact surface A4 at the bottom of the circular ring A5 of the plug 8, which plays a sealing role against the high temperature and high pressure airflow, and is the second sealing defense line.

[0079] The three compensations are: such as Figure 1 As shown, firstly, the lower end of the transfer pipe 7 is clearance-fitted with the displacement ring 9, so that the lower end of the transfer pipe 7 is not absolutely constrained. When the transfer pipe 7 is subjected to high temperature and high pressure gas and undergoes thermal expansion, it can freely contract in the Z direction, reducing structural stress, which is stress compensation. Secondly, since the displacement ring 9 is relatively free in all directions in space, that is, the displacement ring 9 can move along its own radial and axial directions in a limited space, the machining deviation of the exhaust mounting seat 5 and the cabin bleed air mounting seat 12 can be ignored within a small range, and the transfer pipe 7 can be displacement compensated in all directions in space. Thirdly, since the transfer pipe 7 is not fixed to the combustion chamber casing 11, most of the vibration from the engine body is effectively cut off, so that only a small part of the vibration of the whole machine is transmitted to the transfer pipe 7, reducing the impact of the vibration of the whole machine, which is vibration compensation.

Claims

1. A high temperature high pressure floating bleed air seal structure, characterized by: The application relates to a combustion chamber casing (11), an outer casing (6), an adapter pipe (7) and a seat elbow (2), the combustion chamber casing (11) is provided with a gas seal floating mechanism, the outer casing (6) is provided with an air extraction mounting seat (5), one end of the adapter pipe (7) is in gap cooperation with the gas seal floating mechanism and is communicated with the inside of the combustion chamber through the gas seal floating mechanism, the other end of the adapter pipe (7) and one end of the seat elbow (2) are fixed to the air extraction mounting seat (5) through a plurality of connecting components, and the end of the adapter pipe (7) away from the combustion chamber casing (11) is communicated with the outside through the seat elbow (2); The gas seal floating mechanism comprises a displacement ring bush assembly; The displacement ring bush assembly comprises a special nut (10), a displacement ring (9) and a plug cover (8), the plug cover (8) is located in the special nut (10) and is fixedly connected with the special nut (10) and limits the displacement ring (9) in the special nut (10), and the displacement ring (9) can float along the axial and radial directions of the special nut (10); A three-stage cylindrical hole is coaxially arranged on the special nut (10), the three-stage cylindrical hole comprises a nut first-stage hole (D4), a nut second-stage hole (D5) and a nut third-stage hole (D6) which are coaxially and sequentially arranged and have diameters sequentially increasing, an annular table (G4) is arranged on the outer circle of the special nut (10), and a plurality of grooves (g2) are circularly arranged on the annular table (G4); A through hole (D3) is coaxially arranged on the displacement ring (9), the displacement ring (9) comprises a large annular table (G3) and a small annular table (G2), and the small annular table (G2) is connected with the large annular table (G3) through a cylindrical segment; The plug cover (8) comprises a cylinder (A6) and a ring (A5) arranged in the cylinder (A6), the lower end surface of the ring (A5) is coplanar with the lower end surface of the cylinder (A6), the cylinder (A6) is in gap cooperation with the nut third-stage hole (D6) of the special nut (10), and the upper end surface of the cylinder (A6) is coplanar with the upper end surface of the nut third-stage hole (D6) and is sealingly welded; The adapter pipe (7) comprises a thick wall segment (L2) and a thin wall segment (L3), one end of the thin wall segment (L3) is coaxially connected with one end of the thick wall segment (L2), and the inner diameter of the thin wall segment (L3) is consistent with the inner diameter of the thick wall segment (L2); A chamfer R is arranged at the transition of the outer circle of the thick wall segment (L2) and the outer circle of the thin wall segment (L3); The thin wall segment (L3) is in gap cooperation with the through hole (D3) of the displacement ring (9).

2. The high temperature high pressure floating bleed air seal structure of claim 1, wherein: The gas seal floating mechanism comprises a cabin air induction mounting seat (12), the cabin air induction mounting seat (12) is arranged on the combustion chamber casing (11), and the displacement ring bush assembly is detachably connected with the cabin air induction mounting seat (12).

3. The high temperature high pressure floating bleed air seal structure of claim 2, wherein: The cabin bleed air mounting base (12) is provided with a secondary cylindrical hole, which includes a primary hole (D1) and a secondary hole (D2) arranged coaxially. The diameter of the primary hole (D1) is smaller than the diameter of the secondary hole (D2), and the secondary hole (D2) is provided with an internal thread (e1). The cabin bleed air mounting base (12) includes an arc-shaped base plate (G1) and a seat body provided on the arc-shaped base plate (G1).

4. The high-temperature high-pressure floating bleed air seal structure of claim 2 or 3, wherein: The special nut (10) has an external thread (e2) on the outer circular surface at the first-stage hole (D4) of the nut, and an annular surface (A3) with a 100% fit with the top surface of the cabin air bleed mounting base (12) is provided below the second-stage hole (D5) of the nut. The small annular platform (G2), the cylindrical section, and the large annular platform (G3) together form a flange groove (g1). The upper end of the inner hole of the ring (A5) extends upward along the axis and forms an annular flange groove (g3) with the cylinder (A6). The lower end of the inner hole of the ring (A5) extends downward along the axis to form an annular contact surface (A4) with a fit of not less than 80% with the top surface (A1) of the large annular platform (G3).

5. The high temperature high pressure floating bleed air seal structure of claim 1, wherein: The combustion chamber casing (11) is provided with a lug (13), and the annular platform (G4) is provided with a locking hole (D7). The locking hole (D7) is connected to the lug (13) by a steel wire to prevent the special nut (10) from loosening.

6. The high temperature high pressure floating bleed air seal structure of claim 1, wherein: The thick-walled section (L2) is provided with a tubular butterfly platform (G5) at one end away from the thin-walled section (L3), and the tubular butterfly platform (G5) is provided with multiple bolt holes (D9).

7. The high temperature high pressure floating bleed air seal structure of claim 1, wherein: The air extraction mounting base (5) includes an arc plate (G7) and a butterfly-shaped platform (G6) on the arc plate (G7). The arc plate (G7) has multiple rivet holes (D12), and the butterfly-shaped platform (G6) has multiple threaded holes (D11). The arc plate (G7) and the butterfly-shaped platform (G6) are together provided with a through hole (D10).

8. The high temperature high pressure floating bleed air seal structure of claim 1, wherein: The seated bend (2) includes a bend seat (G8) and a bend provided on the bend seat (G8). The bend and the bend seat (G8) are provided with an airflow channel (D13). The bend seat (G8) is provided with multiple screw holes (D14). A conduit (1) is connected to the end of the bend away from the bend seat (G8).

9. The high temperature high pressure floating bleed air seal structure of claim 1, wherein: The connecting assembly includes a bolt (3) and a locking piece (4) fitted onto the bolt (3).

Images