Turbine performance test piece bearing cavity structure

Abstract

The invention provides a turbine performance test piece bearing cavity structure, which belongs to the technical field of aero-engines and comprises a turbine shaft, a front fulcrum bearing and a rear fulcrum bearing, the front fulcrum bearing and the rear fulcrum bearing are mounted on the turbine shaft, a front labyrinth ring is mounted on the turbine shaft on the front side of the front fulcrum bearing, and a rear labyrinth ring is mounted on the turbine shaft on the rear side of the rear fulcrum bearing. A bearing cavity is formed between the front and rear fulcrum bearings; a front sealing ring is fixed to the position, matched with the front labyrinth ring, of the front turbine case, a rear sealing ring is fixed to the position, matched with the rear labyrinth ring, of the rear turbine case, a front air guiding pipe and a rear air guiding pipe are installed on the front sealing ring and the rear sealing ring respectively, an oil inlet pipe and a ventilation pipe are installed on the front turbine case, and a three-way cavity is formed in the front bearing case. After lubricating oil entering from the oil inlet pipe passes through the three-way cavity, one path supplies oil to the front fulcrum bearing through the oil spraying ring, and the other path supplies oil to the rear fulcrum bearing through the oil connecting pipe axially arranged in the bearing cavity and the oil spraying nozzle at the end.

Description

Technical Field

[0001] This application belongs to the field of aero-engine testing, and specifically relates to a bearing cavity structure for a turbine performance test piece. Background Technology

[0002] The normal and stable operation of the lubrication system of an aero-engine is of paramount importance to the reliability of the aero-engine. The bearing cavity is an important component of the aero-engine lubrication system, affecting the performance and lifespan of the aero-engine. The bearing cavity structure mainly includes the bearing housing, sealing device, oil supply pipe, oil return pipe, ventilation pipe, etc., and its function is to prevent lubricating oil leakage within the bearing cavity and ensure the safe and stable operation of the pivot bearing.

[0003] Aero-engine turbines operate under extremely harsh conditions, involving high temperature, high pressure, and high speed. Turbines designed based on theoretical calculations and design experience typically require aerodynamic performance testing on a turbine test facility to further verify their performance. For example... Figure 1 The figure shows a typical turbine performance test specimen rotor connection structure 100, which is supported by two support bearings 101 (the turbine shaft 102, turbine blades 103, and turbine disk 104 together constitute the turbine rotor). In order to ensure that the turbine rotor rotates smoothly during operation and avoid excessive vibration during the test run, the axial span between the two support bearings 101 needs to be set to be relatively large.

[0004] However, when the axial span of the two pivot bearings 101 is large, one bearing cavity is insufficient to accommodate both pivot bearings 101. Therefore, two independent bearing cavity structures are required to achieve lubrication and sealing of the pivot bearings 101. Simultaneously, two sets of lubricating oil pumps and a ground air source need to be designed on the test bench to provide lubricating oil and sealing air to the lubricating cavity of the turbine performance test piece. This increases structural complexity, assembly difficulty, reduces structural reliability, increases the number of test pieces and test equipment parts, and raises production and subsequent maintenance costs. Summary of the Invention

[0005] The purpose of this application is to provide a bearing cavity structure for a turbine performance test piece to solve or mitigate at least one of the problems in the prior art.

[0006] The technical solution of this application is: a bearing cavity structure for a turbine performance test piece, comprising:

[0007] A turbine shaft and a front pivot bearing and a rear pivot bearing mounted on the turbine shaft, a front grate ring is mounted on the turbine shaft in front of the front pivot bearing, and a rear grate ring is mounted on the turbine shaft in rear of the rear pivot bearing, and a bearing cavity is formed between the front pivot bearing and the rear pivot bearing.

[0008] The turbine housing comprises a front turbine casing and a rear turbine casing. A front sealing ring is fixed to the front turbine casing at a position adapted to the front grate ring, and a rear sealing ring is fixed to the rear turbine casing at a position adapted to the rear grate ring. A front bleed pipe is installed on the front sealing ring to introduce sealing bleed air into the front sealing cavity formed between the front grate ring and the front sealing ring. A rear bleed pipe is installed on the rear sealing ring to introduce sealing bleed air into the rear sealing cavity formed between the rear grate ring and the rear sealing ring. An oil inlet pipe and a ventilation pipe are installed on the front turbine casing. A three-way cavity is provided inside the front bearing casing. The lubricating oil entering from the oil inlet pipe passes through the three-way cavity and is supplied to the front pivot bearing through an oil injection ring, and to the rear pivot bearing through an axially arranged oil connecting pipe and an oil injection nozzle at the end of the bearing cavity.

[0009] In at least one embodiment of this application, the front bearing housing is provided with an oil return pool and a first oil return hole connecting the front sealing cavity and the bearing cavity, and an oil return groove connecting the oil return pool and the bearing cavity. At the same time, an oil return pipe is installed on the front bearing housing adapted to the position of the oil return pool. The lubricating oil in the front sealing cavity can flow into the oil return pool along the first oil return hole and the oil return groove, and finally flow out from the oil return pipe.

[0010] In at least one embodiment of this application, the rear bearing housing is provided with a second oil return hole connecting the rear sealing cavity and the bearing cavity, and an inner sleeve is installed on the rear bearing housing. A groove is formed between the inner sides of the rear bearing housing and the front bearing housing. The front bearing housing is provided with a third oil return hole connecting the groove and the oil return pool. The lubricating oil in the rear sealing cavity can flow into the oil return pool along the second oil return hole, the inner sleeve, and the groove, and finally flow out from the oil return pipe.

[0011] In at least one embodiment of this application, the inner sleeve is an inclined structure.

[0012] In at least one embodiment of this application, the oil return groove and the oil return pipe are staggered in the axial direction and have a predetermined distance.

[0013] In at least one embodiment of this application, the rear air duct passes through the rear bearing housing from the front bearing housing side and extends to the rear sealing ring.

[0014] In at least one embodiment of this application, the volume of the front sealing cavity and / or the rear sealing cavity does not exceed 10% of the bearing cavity volume.

[0015] In at least one embodiment of this application, an oil baffle ring is provided between the front grate ring and the front pivot bearing, and an oil catch ring is provided on the rear side of the front pivot bearing. The radial height of the oil baffle ring is not lower than the mating height between the grate teeth of the front grate ring and the coating of the front sealing ring.

[0016] In at least one embodiment of this application, the front side of the rear grate ring is provided with an outwardly biased oblique tooth structure.

[0017] The bearing cavity structure of the turbine performance test piece provided in this application can achieve cooling and lubrication of the two support bearings with a large span through a set of efficient lubricating oil organization system. At the same time, it can achieve rapid and effective sealing of the bearing cavity lubricating oil. Compared with the use of two independent bearing cavity structures, it can greatly simplify the structural complexity, improve reliability, reduce the number of parts, and reduce production and subsequent maintenance costs. Attached Figure Description

[0018] To more clearly illustrate the technical solutions provided in this application, the accompanying drawings will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application.

[0019] Figure 1 This is a schematic diagram of a typical rotor connection structure for a turbine performance test piece.

[0020] Figure 2 This is a schematic diagram of the bearing cavity structure of the turbine performance test piece of this application.

[0021] Figure 3 This is a schematic diagram of the helical tooth structure of the rear grate ring in this application. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings.

[0023] This application provides a bearing cavity structure for a turbine performance test piece. It achieves cooling and lubrication of the bearings at two support points with a large span through a set of efficient lubricating oil organization system, and at the same time achieves rapid and effective sealing of the bearing cavity lubricating oil. Compared with the two independent bearing cavity structures, it solves the problems of complex structure, low reliability and high production and maintenance costs of the two independent bearing cavity structures.

[0024] like Figure 2 As shown, the turbine performance test specimen bearing cavity structure 200 provided in this application includes a turbine shaft 201, a front grate ring 202, a front sealing ring 203, a front air intake pipe 204, a front bearing housing 205, an oil inlet pipe 206, a ventilation pipe 207, a rear air intake pipe 208, a rear bearing housing 209, a rear sealing ring 210, a rear grate ring 211, an oil baffle ring 212, a front pivot bearing 213, an oil catch ring 214, an oil injection ring 215, an oil connecting pipe 216, an oil injector 217, a rear pivot bearing 218, an inner sleeve 219, and an oil return pipe 220.

[0025] The inner rings of the front pivot bearing 213 and the rear pivot bearing 218 are mounted on the turbine shaft 201, and the outer rings of the two pivot bearings are mounted on the front bearing housing 205 and the rear bearing housing 209, respectively. The front pivot bearing 213 and the rear pivot bearing 218 form the support structure for the turbine rotor. The load of the turbine rotor is transferred to the load-bearing housing through the two pivot bearings, thus realizing the load transfer.

[0026] The front pivot bearing 213 and the rear pivot bearing 218 have a large span in the axial direction. For example, a span greater than 500 mm is considered a large span. In order to achieve cooling and lubrication of the two pivot bearings, reduce the number of lubrication system parts, and simplify the structure, a front grate ring 202 is provided on the front side of the front pivot bearing 213 of the turbine shaft, and a front sealing ring 203 is provided corresponding to the front grate ring 202. A front air duct 204 is provided on the front sealing ring 203 for introducing sealing air. The front sealing ring 203 is fixedly connected to the front bearing housing 205. A rear grate ring 211 is provided on the rear side of the rear pivot bearing 218 of the turbine shaft 201, and a rear sealing ring 210 is provided corresponding to the rear grate ring 211. The rear sealing ring 210 is fixedly connected to the rear bearing housing 209, thereby forming a bearing cavity with a large span between the front pivot bearing 213 and the rear pivot bearing 218.

[0027] Oil inlet pipe 206 and ventilation pipe 207 are installed on the front bearing housing 205. The front bearing housing 205 has a three-way cavity 2015. Lubricating oil enters the three-way cavity 2015 through the oil inlet pipe 206 and is divided into two paths. One path of lubricating oil passes through an oil spray ring 215 installed at the end of the three-way cavity 2051 to cool and lubricate the front pivot bearing 213. The other path of lubricating oil is introduced into the rear pivot bearing 218 through an oil connecting pipe 216 installed on the side of the three-way cavity 2051, and lubricates and cools the rear pivot bearing 218 through an oil spray nozzle 217 installed on the oil connecting pipe 216. The rear bleed air pipe 208 is supported on the front bearing housing 205 and the rear bearing housing 209 and connected to the rear sealing ring 210 for introducing sealing bleed air.

[0028] The turbine performance test specimen bearing cavity structure 200 provided in this application is designed with a high-efficiency lubricating oil system to achieve cooling and lubrication of the large-span bearings at two support points. Compared with two independent bearing cavity structures, it can greatly simplify the structural complexity, improve reliability, and enhance lubricating oil efficiency through reasonable structural design.

[0029] In this application, the front bearing housing 205 is provided with a first oil return hole 2052 connecting the front sealing cavity of the front pivot bearing 213 and the bearing cavity, and the rear bearing housing 209 is provided with a second oil return hole 2091 connecting the rear sealing cavity of the rear pivot bearing 2018 and the bearing cavity. The lubricating oil in the front sealing cavity can flow into the bearing cavity through the first oil return hole 2052, and at the same time, the lubricating oil in the rear sealing cavity can flow into the bearing cavity through the second oil return hole 2091. The front bearing housing 205 is further provided with an oil return groove 2053, and an inner sleeve 219 is provided inside the bearing cavity. The inner sleeve 219 guides the lubricating oil flowing out of the second oil return hole 2091 to the splicing position of the front bearing housing 205 and the rear bearing housing 209. A groove 2055 is formed between the inner splicing of the front bearing housing 205 and the rear bearing housing 209. The front bearing housing 205 is further provided with an oil return pool 2056, and at the same time, a groove 25 is located on the side of the rear bearing housing 209 on the front bearing housing 205. The bearing housing is provided with a third oil return hole 2054 at 5 locations. The oil return groove 2053 is connected to the oil return pool 2056 via the third oil return hole 2054. After the lubricating oil lubricates and cools the front pivot bearing 213 and the rear pivot bearing 218, it enters the oil return pool 2056 of the front bearing housing 205 through the first oil return hole 2052 and the oil return groove 2053, the second oil return hole 2091 and the third oil return hole 2054, respectively. Finally, it flows out of the bearing cavity through the oil return pipe 220 installed on the front bearing housing 205 and connected to the oil return pool 2056.

[0030] The integrated bearing cavity structure of the turbine performance test piece in this application can improve lubricating oil efficiency through reasonable structural design. In this application, the inner sleeve 219 has an inclined structure, which allows the lubricating oil to flow quickly to the oil return pool 2056, thereby improving the oil return efficiency at the rear support bearing 218. It is understood that the inclination angle of the inner sleeve 219 can be set as large as possible within the structural limits. The inner sleeve 219 and the rear bearing housing 209 form a double-layer cavity structure, reducing heat conduction from the high-temperature environment outside the rear bearing housing 209, achieving heat insulation for the lubricating oil in the bearing cavity, and reducing the operating temperature of the lubricating oil in the bearing cavity. Furthermore, the oil return groove 2052 and the oil return pipe 220 are provided with a predetermined distance in the axial direction. For example, this predetermined distance can be set to more than 30 cm, thereby forming a large distance between the oil return groove 2052 and the oil return pipe 220 in the axial direction, avoiding the influence of turbine rotor agitation on the inlet of the oil return pipe 220, and improving the oil return efficiency.

[0031] The turbine performance test specimen bearing cavity structure 200 of this application features a compact sealing cavity structure, achieving rapid and effective sealing of the bearing cavity lubricating oil. Specifically, in this application, the honeycomb and coating of the front sealing ring 203 and the rear sealing ring 210, together with the grates of the front grate ring 202 and the rear grate ring 211, form the front sealing cavity Q1 and the rear sealing cavity Q2. Sealing gas enters the front sealing cavity Q1 and the rear sealing cavity Q2 through the front air vent 204 and the rear air vent 208, thereby sealing the lubricating oil inside the bearing cavity. The oil and gas inside the bearing cavity are discharged through the ventilation pipe 207, maintaining stable pressure in the bearing cavity.

[0032] In this application, both the front sealing cavity Q1 and the rear sealing cavity Q2 are small-volume structures, which allows for rapid establishment of sealing pressure and achieves fast and effective sealing. For example, a small-volume structure is defined as one whose volume does not exceed 10% of the bearing cavity volume. The front vent pipe 204, oil inlet pipe 206, ventilation pipe 207, rear vent pipe 208, and oil return pipe 220 are all installed near the front bearing housing 205, reducing the space required for pipe distribution and achieving a compact pipe layout.

[0033] In this application, an oil retaining ring 212 is designed between the front grate ring 202 and the front pivot bearing 213, and an oil receiving ring 214 is provided on the rear side of the front pivot bearing 213. The radial height of the oil retaining ring 212 is not lower than the mating height between the grate teeth of the front grate ring 202 and the coating of the front sealing ring 203, thereby preventing the debris generated by the friction between the grate teeth of the front grate ring 202 and the coating of the front sealing ring 203 from entering the front pivot bearing 213.

[0034] like Figure 3 As shown, the front side of the rear grate ring 211 in this application is designed with an outwardly inclined helical tooth structure 2111 to prevent the debris generated by the friction between the grate teeth of the rear grate ring 211 and the coating of the rear sealing ring 210 from entering the rear pivot bearing 218, thereby improving the reliability of the bearing.

[0035] The bearing cavity structure of the turbine performance test piece provided in this application can achieve cooling and lubrication of the two support bearings with a large span through a set of efficient lubricating oil organization system. At the same time, it can achieve rapid and effective sealing of the bearing cavity lubricating oil. Compared with the use of two independent bearing cavity structures, it can greatly simplify the structural complexity, improve reliability, reduce the number of parts, and reduce production and subsequent maintenance costs.

[0036] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A bearing cavity structure (200) for a turbine performance test piece, characterized in that, include: A turbine shaft (201) and a front pivot bearing (213) and a rear pivot bearing (218) mounted on the turbine shaft (201), a front grate ring (202) is mounted on the turbine shaft (201) in front of the front pivot bearing (213), and a rear grate ring (21) is mounted on the turbine shaft (201) in rear of the rear pivot bearing (218), and a bearing cavity is formed between the front pivot bearing (213) and the rear pivot bearing (218); The turbine housing consists of a front turbine casing (205) and a rear turbine casing (209). A front sealing ring (203) is fixed to the front turbine casing (205) at a position adapted to the front grate ring (202). A rear sealing ring (210) is fixed to the rear turbine casing (209) at a position adapted to the rear grate ring (21). A front air intake pipe (204) is installed on the front sealing ring (203) to introduce sealing air into the front sealing cavity formed between the front grate ring (202) and the front sealing ring (203). A rear air intake pipe (208) is installed on the rear sealing ring (210) to introduce air into the rear grate ring. The rear sealing cavity formed between the ring (211) and the rear sealing ring (210) introduces sealing bleed air. The front turbine casing (205) is equipped with an oil inlet pipe (206) and a ventilation pipe (207). The front bearing casing (205) is provided with a three-way cavity (2051). The lubricating oil entering from the oil inlet pipe (206) passes through the three-way cavity (2051) and then supplies oil to the front pivot bearing (213) through the oil injection ring (215). The other path supplies oil to the rear pivot bearing (218) through the axially arranged oil connecting pipe (216) in the bearing cavity and the oil injection nozzle (217) at the end.

2. The bearing cavity structure of the turbine performance test piece as described in claim 1, characterized in that, The front bearing housing (205) is provided with an oil return pool (2056) and a first oil return hole (2052) connecting the front sealing cavity and the bearing cavity, and an oil return groove (2053) connecting the oil return pool (2056) and the bearing cavity. At the same time, an oil return pipe (220) is installed on the front bearing housing (205) adapted to the position of the oil return pool (2056). The lubricating oil in the front sealing cavity can flow into the oil return pool (2056) along the first oil return hole (2052) and the oil return groove (2053), and finally flow out from the oil return pipe (220).

3. The bearing cavity structure of the turbine performance test piece as described in claim 2, characterized in that, The rear bearing housing (209) is provided with a second oil return hole (2091) connecting the rear sealing cavity and the bearing cavity, and an inner sleeve (219) is installed on the rear bearing housing (209). A groove (2055) is formed between the inner side surfaces of the rear bearing housing (209) and the front bearing housing (205). The front bearing housing (205) is provided with a third oil return hole (2054) connecting the groove (2055) and the oil return pool (2056). The lubricating oil in the rear sealing cavity can flow into the oil return pool (2056) along the second oil return hole (2091), the inner sleeve (219), and the groove (2053), and finally flow out from the oil return pipe (220).

4. The bearing cavity structure of the turbine performance test piece as described in claim 3, characterized in that, The inner sleeve (219) has an inclined structure.

5. The bearing cavity structure of the turbine performance test piece as described in claim 3, characterized in that, The oil return groove (2053) and the oil return pipe (220) are staggered in the axial direction and have a predetermined distance.

6. The bearing cavity structure of the turbine performance test piece as described in claim 1, characterized in that, The rear air duct (208) passes through the rear bearing housing (209) from the front bearing housing (205) and extends to the rear sealing ring (210).

7. The bearing cavity structure of the turbine performance test piece as described in claim 1 or 2, characterized in that, The volume of the front sealing cavity and / or the rear sealing cavity shall not exceed 10% of the bearing cavity volume.

8. The bearing cavity structure of the turbine performance test piece as described in claim 1, characterized in that, An oil baffle ring (212) is provided between the front grate ring (202) and the front pivot bearing (213), and an oil collection ring (214) is provided on the rear side of the front pivot bearing (213). The radial height of the oil baffle ring (212) is not lower than the mating height between the grate teeth of the front grate ring (202) and the coating of the front sealing ring (203).

9. The bearing cavity structure of the turbine performance test piece as described in claim 1, characterized in that, The front side of the rear comb ring (211) is provided with an outwardly inclined tooth structure (2111).

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