CN213775555U - Low-temperature high-rotating-speed floating ring sealing test device for rocket engine turbine pump - Google Patents

Low-temperature high-rotating-speed floating ring sealing test device for rocket engine turbine pump Download PDF

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Publication number
CN213775555U
CN213775555U CN202022146741.4U CN202022146741U CN213775555U CN 213775555 U CN213775555 U CN 213775555U CN 202022146741 U CN202022146741 U CN 202022146741U CN 213775555 U CN213775555 U CN 213775555U
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floating ring
shell
sealing
test device
cavity
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杨军
张小平
郑国真
李勇
姜圣杰
赵玉龙
周小义
任荣波
张士强
周旭
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Lanjian Spaceflight Technology Co ltd
Landspace Technology Co Ltd
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Lanjian Spaceflight Technology Co ltd
Landspace Technology Co Ltd
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Abstract

The utility model provides a low-temperature high-rotating-speed floating ring sealing test device for a rocket engine turbine pump, which comprises a shell, a shell I, a shell II and a shell III; a stepped spindle disposed inside the housing; the front floating ring sealing assembly and the rear floating ring sealing assembly are sleeved on the stepped spindle; the front floating ring seal assembly and the rear floating ring seal assembly form a test cavity in the housing II. Rocket engine is low temperature high rotational speed floating ring seal test device for turbo pump, functional strong, compatible good, the performance is good under low temperature high speed state, can carry out multiple floating ring low temperature seal test, both can verify the sealing performance of floating ring subassembly, also can examine the rationality of floating ring structure.

Description

Low-temperature high-rotating-speed floating ring sealing test device for rocket engine turbine pump
Technical Field
The utility model relates to a floating ring seal application field for rocket engine turbo pump, and in particular to multipurpose low temperature high rotational speed floating ring seal test device for rocket engine turbo pump is applied to multiple rocket engine floating ring seal assembly's batch selective examination experiment, running-in test and research nature test.
Background
The high-speed rotating turbine pump is an important component of a liquid rocket engine, the floating ring sealing component is a key part in the turbine pump, and the reliability of the floating ring seal is the basis of the reliability of the engine. Under the working conditions of low temperature and high rotating speed, the sealing performance of the floating ring sealing assembly is related to factors such as working pressure, rotating speed and floating ring clearance. The floating ring sealing test device can simulate the real working condition of the engine turbopump, and can perform low-temperature operation test partial working condition examination of the inlet pressure change of the sealing test cavity and the rotating speed boundary and verify the rationality of the sealing scheme, the structural design and the performance. The device is designed with the advantages of good compatibility of a sealing product on the testing device, convenience in disassembly and assembly, high utilization rate, good performance of the testing device in the sealing test operation in the low-temperature environment, stable structure, no shrinkage deformation in the low-temperature environment, system stability and safety and reliability of the stepped spindle, and the problems of critical rotating speed avoidance and the like due to the working rotating speed. At present, a floating ring sealing test device suitable for the working conditions of low temperature and high rotating speed is not found.
Chinese patent CN 108708802 a discloses a low-temperature high-speed end face seal test device for a liquid rocket engine turbine pump. The device is applied to in the selective examination of liquid hydrogen liquid oxygen propellant's rocket engine end face seal subassembly is experimental, the running-in is experimental and the research nature is experimental, assembles the end face seal subassembly product the utility model discloses among the testing device, the operational environment of simulation engine turbo pump. This device has the following disadvantages: the test method is only used for end face sealing product tests and cannot be used for high-speed low-temperature operation examination tests of floating ring sealing products.
Therefore, how to provide a low-temperature high-rotation-speed floating ring seal test device for a rocket engine turbine pump, which is suitable for a high-speed low-temperature operation examination test of a floating ring seal product, is a technical problem to be solved urgently by technical personnel in the field.
SUMMERY OF THE UTILITY MODEL
In order to solve at least part above-mentioned technical problem, the utility model provides a rocket engine is low temperature high rotational speed floating ring seal test device for turbo pump, this test device includes: a housing comprising housing I, housing II and housing III; the stepped spindle is arranged in the shell, one end of the stepped spindle is fixed on the shell I through a front bearing, and the other end of the stepped spindle penetrates through the shell II and is fixed on the shell III through a rear bearing; the front floating ring sealing assembly and the rear floating ring sealing assembly are sleeved on the stepped spindle; the front floating ring sealing assembly is fixed to the shell II through a front floating ring shell, the rear floating ring sealing assembly is fixed to the shell II through a rear floating ring shell, and the front floating ring sealing assembly and the rear floating ring sealing assembly form a test cavity in the shell II.
In some embodiments, in the low-temperature high-rotation-speed floating ring seal test device for the rocket engine turbine pump, a first circular groove is formed in the front end surface of the inner wall of the casing I, 3 first leather cups are used for sealing in the first circular groove, the first leather cups are fixed on the inner wall of the casing I through first leather cup pressing covers, and a leakage cavity is formed by the first circular groove, the casing I and the front floating ring assembly; the rear floating ring sealing assembly, the rear end face of the inner wall of the shell II and the shell III enclose a secondary leakage cavity.
In some embodiments, in the low-temperature high-rotation-speed floating ring seal test device for a rocket engine turbine pump, 3 fourth through holes communicated with the first leakage cavity and 3 fifth through holes communicated with the second leakage cavity are formed in the shell I; and the shell II is provided with 3 sixth through holes communicated with the first leakage cavity and 3 seventh through holes communicated with the second leakage cavity.
In some embodiments, in the test device for the low-temperature high-speed floating ring seal for the rocket engine turbine pump, the test device further comprises a front end cover arranged on the shell I and a rear end cover arranged on the shell III.
In some embodiments, in the low-temperature high-rotation-speed floating ring seal test device for a rocket engine turbine pump, a second circular groove is formed in the rear end cover, 3 second cups are used for sealing in the second circular groove, and the second cups are fixed to the rear end cover through second cup pressing covers.
In some embodiments, in the low-temperature high-speed floating ring seal testing device for the rocket engine turbine pump, a front bearing cooling cavity is formed between the front end cover and the first leather cup; and a rear bearing cooling cavity is formed between the rear end cover and the second large leather cup.
In some embodiments, in the low-temperature high-rotation-speed floating ring seal test device for the rocket engine turbine pump, the housing I is provided with an eighth through hole and a ninth through hole which are communicated with the front bearing cooling cavity, the eighth through hole is used for inputting a bearing cooling medium into the front bearing cooling cavity, and the ninth through hole is used for discharging the cooling medium in the front bearing cooling cavity; the front end cover is provided with a tenth through hole and an eleventh through hole which are communicated with the front bearing cooling cavity, the tenth through hole is used for detecting the pressure value of the front bearing cooling cavity, and the eleventh through hole is used for detecting the temperature value of the front bearing cooling cavity; and a twelfth through hole and a thirteenth through hole which are communicated with the rear bearing cooling cavity are formed in the shell III, the twelfth through hole is used for inputting bearing cooling media into the rear bearing cooling cavity, and the thirteenth through hole is used for discharging the cooling media in the rear bearing cooling cavity.
In some embodiments, in the low-temperature high-speed floating ring seal test device for a rocket engine turbine pump, a third circular groove is formed in the inner side wall of the rear end of the housing II, the third circular groove is sealed by using 3 third cup seals, and the third circular groove separates the rear bearing cooling cavity from the two leakage cavities.
In some embodiments, in the low-temperature high-speed floating ring seal test device for a rocket engine turbine pump, the other end of the stepped main shaft penetrates through the rear end cover, and the other end is connected with a speed increasing box arranged outside the casing through a flexible coupling.
In some embodiments, in the low-temperature high-speed floating ring seal test device for a rocket engine turbine pump, sealing gaskets are arranged between the front floating ring seal assembly and the casing, between the rear floating ring seal assembly and the casing, between the front end cover and the casing, and between the rear end cover and the casing; the sealing gasket material is soft aluminum subjected to annealing treatment; the machining precision of the matching surface of the stepped main shaft and the front bearing, the matching surface of the stepped main shaft and the rear bearing, the matching surface of the stepped main shaft and the front floating ring sealing assembly and the matching surface of the stepped main shaft and the rear floating ring sealing assembly is 0.8 grade, and the form and position tolerance is less than 0.02 mm.
The embodiment of the utility model provides a rocket engine is low temperature high rotational speed floating ring seal test device for turbo pump has one of following beneficial effect at least:
rocket engine is low temperature high rotational speed floating ring seal test device for turbo pump, functional strong, compatible good, the performance is good under low temperature high speed state, can carry out multiple floating ring low temperature seal test, both can verify the sealing performance of floating ring subassembly, also can examine the rationality of floating ring structure.
Rocket engine is low temperature high rotational speed floating ring seal test device for turbo pump, can carry out 2 sets of seal assembly's experiments simultaneously, compare other test device and improve 1 doubly efficiency.
Rocket engine is low temperature high rotational speed floating ring seal test device for turbo pump, can have to let out one and two float ring subassembly that let out experimental, application range is wide.
Rocket engine is low temperature high rotational speed floating ring seal test device for turbo pump, the design of ladder main shaft is the rigidity axle, makes its operating speed avoid first-order critical speed, has guaranteed sufficient rigidity and stability. The stepped spindle performs action balance and weight removal, and the stability of the test device in a high-speed (0-36000r/min) state is further improved.
Rocket engine is low temperature high rotational speed floating ring seal test device for turbo pump, each component part carries out cryrogenic treatment in the liquid nitrogen before the finish machining, guarantees not shrink deformation of test device in the low temperature test process.
Rocket engine is low temperature high rotational speed floating ring seal test device for turbo pump, coaxial precision is high, rational in infrastructure, convenient assembling. The machining precision of the key matching surfaces of the stepped spindle, the shell and parts assembled on the stepped spindle is required to be 0.8 grade, and the geometric tolerance is required to be less than 0.02mm, so that the coaxiality precision of the stepped spindle of the testing device and the driving shaft of the testing table is ensured.
Drawings
Fig. 1 is a schematic structural diagram of a low-temperature high-speed floating ring seal test device for a rocket engine turbine pump according to an embodiment of the present invention.
Fig. 2 is a left side view structural schematic diagram of the low-temperature high-speed floating ring seal test device for the rocket engine turbine pump according to one embodiment of the present invention.
Fig. 3 is a schematic diagram of a structure of a low-temperature high-speed floating ring seal test device for a rocket engine turbine pump according to an embodiment of the present invention from the right.
Fig. 4 is an assembly schematic diagram of a low-temperature high-speed floating ring seal test device for a rocket engine turbine pump according to one embodiment of the present invention.
Fig. 5 is a test flowchart of the low-temperature high-speed floating ring seal test device for the rocket engine turbine pump according to one embodiment of the present invention.
Reference numerals:
1 represents a shell I, 2 represents a shell II, 3 represents a shell III, 4 represents a disc spring retainer, 5 represents an adjusting gasket, 6 represents a rear end cover, 7 represents a second cup gland, 8 represents a second cup, 9 represents a rear bearing pressure plate, 10 represents a bearing intermediate sleeve, 11 represents a third cup gland, 12 represents a rear bearing pressure nut, 13 represents a front bearing pressure nut, 14 represents a front lock nut, 15 represents a rear lock nut, 16 represents a rear bearing pressure sleeve, 17 represents a front bearing pressure plate, 18 represents a front bearing pressure sleeve, 19 represents a third cup, 20 represents a front end cover, 21 represents a main shaft, 22 represents a front shaft sleeve, 23 represents a rear shaft sleeve, 24 represents a bearing pre-tightening disc spring, 25 represents a graphite seal gasket, 26 represents a third cup gasket, 27 represents a second cup gasket, 28 represents a first cup gasket, 29 represents a first shell seal gasket, 30 represents a second shell seal gasket, 31 represents a third housing seal gasket, 32 represents a first filler neck seal gasket, 33 represents a second filler neck seal gasket, 34 represents a third filler neck seal gasket, 35 represents a fourth filler neck seal gasket, 36 represents a first screwed-in filler neck, 37 represents a second screwed-in filler neck, 38 represents a third screwed-in filler neck, 39 represents a fourth screwed-in filler neck, 40 represents a cryogenic bearing, 41 represents a key A5X15, 42 represents a pin A8X15, 43 represents a pin A8X65, 44 represents a first bolt, 45 represents a second bolt, 46 represents a third bolt, 47 represents a front floating ring seal assembly, 48 represents a rear floating ring seal assembly, 49 represents a first cup, 50 represents a first cup gland, 51 represents a leakage chamber, 52 represents a second leakage chamber, 53 represents a front bearing cooling medium inlet, 54 represents a front bearing cooling medium outlet, 55 represents a rear bearing cooling medium inlet, 56 represents a rear bearing cooling medium outlet, 57 represents a process oxygen seal one-way discharge outlet, 58 represents a process oxygen seal two-way discharge outlet, 59 represents an oxygen seal medium inlet, 60 represents an oxygen seal one-way discharge outlet, 61 represents an oxygen seal two-way discharge outlet, 62 represents an oxygen seal one-way discharge cavity pressure measuring port, 63 represents an oxygen seal two-way discharge cavity pressure measuring port, 64 represents an oxygen seal two-way discharge cavity temperature measuring port, 65 represents an oxygen seal medium inlet pressure measuring port, 66 represents a process oxygen seal one-way discharge pressure measuring port, 67 represents a process oxygen seal discharge cavity temperature measuring port, 68 represents an oxygen seal medium inlet temperature measuring port, 69 represents a process oxygen seal two-way discharge pressure measuring port, 70 represents a bearing cooling pressure measuring port, 71 represents a bearing cooling temperature measuring port, and 72 represents a test cavity.
Detailed Description
Reference will now be made in detail to various exemplary embodiments of the invention, which should not be considered limiting of the invention, but rather should be understood to be a more detailed description of certain aspects, features and embodiments of the invention.
It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Further, to the extent that numerical ranges are recited in the present disclosure, it is understood that the upper and lower limits of the range, and each intervening value therebetween, is specifically disclosed. Every smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in a stated range is also encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only the preferred methods and materials are described in this disclosure, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present disclosure. All documents mentioned in this specification are incorporated by reference herein for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.
It will be apparent to those skilled in the art that various modifications and variations can be made in the embodiments of the present disclosure without departing from the scope or spirit of the disclosure. The specification and examples are exemplary only.
As used herein, the terms "comprising," "including," "having," "containing," and the like are open-ended terms that mean including, but not limited to.
As used herein, "and/or" includes any and all combinations of the stated items.
The present invention will be further described with reference to the following detailed description and accompanying drawings.
As shown in fig. 1 to 5, the utility model provides a rocket engine is low temperature high rotational speed floating ring seal test device for turbo pump, this test device includes:
a housing comprising housing I1, housing II2, and housing III 3. The shell of the testing device is made of 2Cr13 stainless steel;
a stepped main shaft 21 arranged inside the housing, wherein one end of the stepped main shaft 21 is fixed on the housing I1 through a front bearing, and the other end of the stepped main shaft 21 passes through the housing II2 and is fixed on the housing III3 through a rear bearing; the stepped main shaft 21 is positioned in the shell, the stepped main shaft 21 passes through a flat key, a bearing intermediate sleeve 10, a front bearing and a rear bearing support which are arranged in the shell, the front bearing is arranged in a front bearing pressing sleeve 18 and is pressed by a front bearing pressing plate 17, a front bearing pressing nut 13 (reverse thread) is locked, and the front bearing pressing sleeve 18 is fastened on the shell I1 through a bolt; the rear bearing is installed in the rear bearing pressing sleeve 16 and is locked by the rear bearing compression nut 12. The disc spring 24, the disc spring retainer 4, the adjusting shim 5, the rear bearing pressure plate 9 and the bolt are tightly fixed on the shell III3 through the bearing pretension. The bearing pre-tightening disc spring 24, the disc spring retainer 4 and the adjusting gasket 5 are used for applying axial pre-tightening force to the front bearing and the rear bearing during assembly. The low temperature test bearing selects angular contact ball bearings to pair for use, pays attention to the bearing installation direction, adopts bearing pre-tightening disc springs 24 to compress the bearing, and provides axial pre-tightening force for the bearing by utilizing the compression of the pre-tightening disc springs, so that the bearing can bear axial force and radial force simultaneously.
A front floating ring seal assembly 47 and a rear floating ring seal assembly 48 which are sleeved on the stepped spindle 21; the front floating ring seal assembly 47 is secured to the housing II2 by a front floating ring housing, the rear floating ring seal assembly 48 is secured to the housing II2 by a rear floating ring housing, the front and rear floating ring seal assemblies 47, 48 forming a test chamber 72 within the housing II 2.
The shaft system also comprises 4 sets of lock nuts which are made of 2Cr13 stainless steel and can ensure that the nuts are not adhered to the threads of the stepped spindle 21, wherein the front lock nuts are reverse threads and can play an effective anti-loose effect when the stepped spindle 21 runs at high speed. The locking nuts are all in threaded connection with the stepped spindle 21 and comprise a front locking nut 14 and a rear locking nut 15, 2 sets of locking nuts are respectively used for fastening the front floating ring shaft sleeve and the rear floating ring shaft sleeve on the stepped spindle 21, 2 sets of locking nuts are used for fixing a front bearing and a rear bearing, and the front locking nuts are reverse threads.
For carrying out liquid rocket engine turbopump floating ring seal low temperature high speed batch selective examination experiment and running-in test, the sealed sealing performance of examination turbopump floating ring, test device, satisfy operating condition under-196 ℃ -186 ℃ low temperature and 36000r/min rotational speed to do not shrink deformation under low temperature environment, simultaneously, ladder main shaft 21 has dynamic stability, and the ladder owner satisfies the requirement that low-speed dynamic balance went the heavy.
With sealed product assembly to the utility model discloses among the testing device, the true operational environment of simulation engine turbopump examines the sealing performance and the structural rationality of seal assembly product design to the sealing performance of detection seal assembly product that can be quantitative solves the various problems that appear in the seal assembly product design, provides important foundation and technical support for improving product design.
In the scheme, the stepped spindle 21 is made of 9Cr18 stainless steel, dynamic balance is required during processing, the dynamic balance rotating speed is not lower than 4000r/min, and the dynamic balance precision grade is G1 grade.
In the scheme, a first circular groove is formed in the front end face of the inner wall of the shell I1, 3 first leather cups 49 are used for sealing in the first circular groove, the first leather cups 49 are fixed on the inner wall of the shell I1 through first leather cup pressing covers 50, and the first circular groove, the shell I1 and the front floating ring assembly form a leakage cavity 51;
the rear floating ring seal assembly 48, the rear end face of the inner wall of the housing II2 and the housing III3 enclose a secondary leakage cavity 52.
In the above scheme, the casing I1 is provided with 3 fourth through holes communicated with the first leakage cavity 51 and 3 fifth through holes communicated with the second leakage cavity 52; and 3, the fourth through holes are distributed and used for connecting a pressure sensor, a temperature sensor and a leakage sensor to detect the pressure value, the temperature value and the leakage in the leakage cavity 51. And 3 fifth through holes are distributed and used for connecting a pressure sensor, a temperature sensor and a leakage sensor and detecting the pressure value, the temperature value and the leakage in the second leakage cavity 52.
The shell II2 is provided with 3 sixth through holes communicated with the first leakage cavity 51 and 3 first through holes communicated with the second leakage cavity 52. And 3, the sixth through holes are distributed and used for connecting a pressure sensor, a temperature sensor and a leakage sensor to detect a pressure value, a temperature value and a leakage in the leakage cavity 51. And 3, the seventh through holes are distributed and used for connecting a pressure sensor, a temperature sensor and a leakage sensor and detecting the pressure value, the temperature value and the leakage in the second leakage cavity 52.
In the scheme, the inlet and outlet pipelines and the sensor are connected in a horn-mouth ball head sealing mode, and the ball head sealing effect is good after multiple times of verification;
in the above solution, the testing device further comprises a front end cap 20 disposed on the housing I1 and a rear end cap 6 disposed on the housing III 3.
In the scheme, the rear end cover 6 is provided with a second circular groove, 3 second leather cups 8 are used for sealing in the second circular groove, and the second leather cups 8 are fixed on the rear end cover 6 through second leather cup pressing covers 7.
In the above scheme, a front bearing cooling cavity is formed between the front end cover 20 and the first leather cup 49; and a rear bearing cooling cavity is formed between the rear end cover 6 and the second large leather cup. The front bearing cooling cavity and the rear bearing cooling cavity are sealed, and liquid nitrogen is prevented from leaking from the spline end of the stepped shaft.
In the above scheme, the housing I1 is provided with an eighth through hole and a ninth through hole, the eighth through hole is communicated with the front bearing cooling cavity, the eighth through hole is used for inputting a bearing cooling medium into the front bearing cooling cavity, and the ninth through hole is used for discharging the cooling medium in the front bearing cooling cavity.
The front end cover 20 is provided with a tenth through hole and an eleventh through hole which are communicated with the front bearing cooling cavity, the tenth through hole is used for detecting the pressure value of the front bearing cooling cavity, and the eleventh through hole is used for detecting the temperature value of the front bearing cooling cavity.
A twelfth through hole and a thirteenth through hole which are communicated with the rear bearing cooling cavity are formed in the shell III3, the twelfth through hole is used for inputting bearing cooling media into the rear bearing cooling cavity, and the thirteenth through hole is used for discharging the cooling media in the rear bearing cooling cavity.
In the above scheme, a third circular groove is formed in the inner side wall of the rear end of the shell II2, the third circular groove is sealed by using 3 third leather cups 19, and the third circular groove separates the rear bearing cooling cavity from the second leakage cavity 52. A third cup 19 is secured to the third circular groove with a third cup gland 11, adjacent third cups 19 being separated by a third cup gasket 26.
In the above scheme, the first leather cup 49, the second leather cup 8 and the third leather cup 19 all adopt polytetrafluoroethylene and graphite, and a good sealing effect is achieved during a low-temperature test. Set up first gasket interval between adjacent first leather cup 49, first gasket is set up the aluminium gasket interval between aluminium gasket, adjacent second leather cup 8 and sets up the aluminium gasket interval between adjacent third leather cup 19, and the aluminium gasket is for getting ideal sealed effect, need select the gasket of suitable thickness according to the compressive capacity, and the aluminium gasket has good sealed effect under the low temperature environment.
In the above scheme, the other end of the stepped spindle 21 passes through the rear end cover 6, and the other end is connected with a speed increasing box arranged outside the housing through a flexible coupling.
In the above scheme, sealing gaskets are arranged between the front floating ring sealing assembly 47 and the shell, between the rear floating ring sealing assembly 48 and the shell, between the front end cover 20 and the shell, and between the rear end cover 6 and the shell; the sealing gasket material is soft aluminum subjected to annealing treatment.
The machining precision of the matching surface of the stepped main shaft 21 and the front bearing, the matching surface of the stepped main shaft 21 and the rear bearing, the matching surface of the stepped main shaft 21 and the front floating ring sealing assembly 47 and the matching surface of the stepped main shaft 21 and the rear floating ring sealing assembly 48 is 0.8 grade, and the form and position tolerance is less than 0.02 mm.
In the above scheme, the cooling device further comprises a front bearing cooling medium inlet 53, a front bearing cooling medium outlet 54, a rear bearing cooling medium inlet 55 and a rear bearing cooling medium outlet 56.
In the above embodiment, the stepped spindle 21 is a rigid shaft, and dynamic balance and weight removal are performed during processing.
In the scheme, each component part of the test device needs to be subjected to cryogenic treatment in liquid nitrogen before finish machining, so that the part is prevented from being influenced by low temperature to shrink and deform during testing.
In the scheme, the device further comprises an oxygen sealing first-outlet cavity pressure measuring port 62, an oxygen sealing second-outlet cavity pressure measuring port 63, a process oxygen sealing leakage cavity temperature measuring port 67, an oxygen sealing medium inlet cavity temperature measuring port 68, a process oxygen sealing second-outlet cavity pressure measuring port 69 and a bearing cooling pressure measuring port 70.
The utility model discloses in one of them embodiment, as shown in fig. 4, need press cover 18 and back bearing pressure cover 16 with casing I1, casing II2, casing III3, front bearing during processing and need assemble, join in marriage the drilling pin hole, beat the pin, the hole of processing front bearing pressure cover 18 before the alignment on the precision boring machine, the hole of reprocessing back bearing pressure cover 16 guarantees that two hole axialities are not more than the
Figure BDA0002703155750000101
So as to ensure the assembly precision and the coaxiality of the shafting. In the above embodiment, the key includes a key A5X 1541, a pin A8X 1542, a pin A8X 6543, a first bolt 44, a second bolt 45, and a third bolt 46.
In the scheme, the test device is further provided with a process oxygen sealing first-path outlet 6057, a process oxygen sealing second-path outlet 6158, an oxygen sealing medium inlet 59, an oxygen sealing first-path outlet 60 and an oxygen sealing second-path outlet 61.
In the above scheme, the test device further comprises: a first filler neck sealing gasket 32, a second filler neck sealing gasket 33, a third filler neck sealing gasket 34, a fourth filler neck sealing gasket 35, a first screwed-in filler neck 36, a second screwed-in filler neck 37, a third screwed-in filler neck 38 and a fourth screwed-in filler neck 39.
Test device, its assembly process as follows:
the outer diameters of the front and rear shaft sleeves 23 and the inner diameter of the floating ring are measured and recorded, the front shaft sleeve 22 and the rear shaft sleeve 23 are mounted on the shaft according to fig. 1 to 3, and a front lock nut (reverse thread) and a rear lock nut are respectively locked by a special spanner.
Graphite seal 25 is installed in a seal groove in housing II2 as shown in FIGS. 1-3, and rear floating ring seal assembly 48 is installed on housing II2 and tightened with grease-coated bolts and saddle washers.
Graphite packing 25 is installed in a seal groove in housing I1 as shown in fig. 1, and front floating ring seal assembly 47 is installed on housing I1 and tightened with grease-coated bolts and saddle washers.
The bearing is installed into the front bearing pressing sleeve 18 according to the direction shown in the figure, and then the front bearing pressing plate 17 is installed and screwed down by bolts.
With housing I1 positioned horizontally, stepped spindle 21 is shown passing through housing I1 without allowing scoring of the front floating ring assembly inner race.
The first cup 49, first cup washer 28, first cup cover 50 are shown installed in the housing I1, noting the installation orientation of the first cup 49.
The flat key is arranged in a key groove of the shaft, the bearing middle sleeve 10 is arranged in a bearing assembly, then the bearing assembly is arranged on the shaft and is connected with the shell I1, a positioning pin is inserted, and the bearing assembly is screwed by a bolt; and (4) installing a front bearing lock nut, temporarily not screwing, and screwing after the connection of the shells I1, II and III is finished.
The shell I1 assembly is vertically placed on an assembly table, a first shell sealing gasket 29 is installed on the outer edge of a boss of a shell I1, then the shell II2 assembly is slowly penetrated through a shaft system to be connected with the shell I1 assembly, the inner ring of the floating ring assembly is not allowed to be scratched, a positioning pin is inserted, and the positioning pin and the gasket are used for fastening.
The second housing sealing gasket 30 is installed in the sealing groove of housing II2, housing III3 is installed on housing II2, and the positioning pin is inserted and fastened with bolt and gasket.
The second cup 8, the second cup gasket 27 and the second cup cover 7 in the housing III3 are installed into the housing III3 according to the drawing, and the installation direction of the second cup 8 is noted.
The flat key is arranged in a flat key groove of a stepped spindle 21, a bearing intermediate sleeve 10 is arranged on a shaft, and then the bearing is arranged on the bearing intermediate sleeve 10 according to the direction shown in the figure; the rear bearing press sleeve 16 is mounted and bolted to the housing III 3.
A disc spring 24 is pre-tightened on a bearing, a disc spring retainer 4 is pressed on the bearing, an adjusting gasket 5 with the calculated compression amount is placed on the disc spring retainer 4, a rear bearing pressing plate 9 is installed and fastened by a screw, and a front bearing pressing nut 12 and a rear bearing pressing nut 12 are fastened by a special spanner.
The third housing sealing gasket 31 is fitted into the sealing groove of the housing III3, and the rear end cap 6 is closed and screwed down with bolts.
The second leather cup 8, the second leather cup gasket 27 and the second leather cup pressing plate are arranged according to the direction of the figure and are screwed by bolts.
The first housing sealing gasket 29 is installed in the sealing groove of the housing I1, and the front end cap 20 is closed and screwed down.
All the screwed pipe connecting nozzles and the gaskets are installed in the corresponding threaded holes.
The front floating ring assembly and the rear floating ring assembly are symmetrically arranged, the front floating ring sealing assembly 47 is fixed on the shell II2 through a front floating ring shell, and a front test cavity 72 is formed in the shell II 2; the rear floating ring seal assembly 48 is secured to the housing II2 by a rear floating ring housing and forms a rear test cavity 72 within the housing II 2.
A first circular groove is processed on the inner side of the front end of the shell I1, and 3 sealing first leather cups 49 are arranged in the first circular groove, so that a leakage cavity 51 is formed between the shell I1 and the front floating ring assembly; the shell I1 is provided with 6 through holes, wherein 3 fourth through holes are communicated with the first leakage cavity 51 and are respectively used for measuring the pressure, the temperature and the two-way sealing leakage quantity of the leakage cavity, and the other 3 fifth through holes are communicated with the second leakage cavity 52 of the floating ring sealing assembly and are respectively used for measuring the pressure, the temperature and the leakage quantity of the first sealed leakage cavity 51.
The inner side of the rear end of the shell II2 is also provided with a third circular groove which is sealed by 3 third leather cups 19 and used for separating the bearing cooling cavity from the two leakage cavities 52. Two leakage cavities 52 are formed between the rear end of the shell II2 and the right floating ring assembly, 6 through holes are additionally processed on the shell II2, wherein 3 sixth through holes are communicated with one leakage cavity 51 and are respectively used for measuring the pressure, the temperature and the first sealing leakage quantity of the leakage cavities, and the other 3 seventh through holes are communicated with the two leakage cavities 52 of the floating ring sealing assembly and are respectively used for measuring the pressure, the temperature and the leakage quantity of the two sealed leakage cavities 52.
The front end cover 20 is connected with a shell I1, a front bearing cooling cavity is formed between the first leather cup 49 at the front end and the front end cover 20, an eighth through hole and a ninth through hole are formed in the shell I1, the eighth through hole at the lower end is a bearing cooling medium inlet, the ninth through hole at the upper end is a cooling medium outlet, and meanwhile, a tenth through hole and an eleventh through hole are formed in the front end cover 20 and are used for measuring the pressure and the temperature of the bearing cooling cavity.
The rear end cover 6 is connected with the shell III3, a rear bearing cooling cavity is formed between the second leather cup 8 at the rear end and the rear end cover 6, a twelfth through hole and a thirteenth through hole are machined in the shell III3, the twelfth through hole at the lower end is a bearing cooling medium inlet, and the thirteenth through hole at the upper end is a cooling medium outlet.
The stepped main shaft 21 penetrates out of the rear end cover 6 and is connected with an external speed increasing box through a specially designed flexible coupling.
The rear end cover 6 is provided with a second circular groove, 3 second sealing leather cups are installed in the second circular groove, a gasket is arranged between the 3 second sealing leather cups, and the 3 second sealing leather cups are fixed on the rear end cover 6 through a second leather cup pressing cover 7 and used for sealing a bearing cooling cavity to prevent liquid nitrogen from leaking from the spline end of the stepped shaft to reduce the cooling capacity of liquid nitrogen in the bearing cavity and damage a gear box.
Sealing gaskets are arranged between the engine floating ring assembly and the shell, between the front end cover 20 and the shell, and between the rear end cover 6 and the shell; the shell sealing gasket material is aluminum, and annealing treatment is carried out after mechanical processing.
And a bearing pre-tightening disc spring 24, a disc spring retainer 4 and an adjusting gasket 5 are arranged between the rear bearing and the rear bearing gland and are used for applying axial pre-tightening force to the front bearing and the rear bearing during assembly.
All component parts of the test device need to be subjected to cryogenic treatment in liquid nitrogen before finish machining, and the parts are prevented from being affected by low temperature to shrink and deform during testing.
The machining precision of the matching surface of the stepped main shaft 21 and the front bearing, the matching surface of the stepped main shaft 21 and the rear bearing and the matching surface of the stepped main shaft 21 and the engine rotating ring are all 0.8 grade, and the form and position tolerance is less than 0.02 mm.
Because the floating ring seal assembly product kind is many, and every batch of product quantity is more, carries out the low temperature operation test examination, and the test device assembly is dismantled frequently, and the rate of utilization is high, to the part that has threaded connection on the ladder main shaft 21, chooses for use the material different with ladder main shaft 21: the stepped spindle 21 is made of 9Cr18 stainless steel, and the rear bearing compression nut 12, the front bearing compression nut 13, the front locking nut and the rear locking nut are made of 2Cr13 stainless steel so as to prevent adhesion when the threads are matched and frequently disassembled and assembled.
After the assembly is completed, clearance inspection needs to be carried out on the sealing effect between the shells by using the feeler gauge.
The stepped main shaft 21 passes through the second leather cup 8 for sealing and is connected with the high-speed output shaft of the gearbox through a specially designed flexible coupling.
After the test device is assembled, the rotation runout of the stepped spindle 21 is required to be not more than 0.02mm, a specially designed coaxial adjusting tool is adopted, the vertical offset of the end faces of the stepped spindle 21 and the rear end cover 6 is adjusted to be not more than 0.02mm, and otherwise, a shaft system needs to be adjusted or reassembled.
The test device is integrally placed on the support, the circular runout of the high-speed shaft of the rechecking gearbox is not more than 0.02mm, the coaxiality of the stepped main shaft 21 and the high-speed shaft of the gearbox of the test device is adjusted, and the vertical offset of the end face of the high-speed shaft of the gearbox and the end face of the rear end cover 6 is not more than 0.02 mm. The left and right offset between the high-speed shaft of the gear box and the stepped main shaft 21 of the test device is not more than 0.02 mm.
During low temperature test, the test device can wholly sink after letting in liquid nitrogen, and in order to guarantee that the upper and lower offset of gearbox high-speed axle and test device ladder main shaft 21 is not more than 0.02mm, so when installing test device, ladder main shaft 21 central height need have the improvement volume.
The inlet and outlet connecting pipes in the test device pass through engineering hydrodynamics accounting, and the flow resistance of the inlet and outlet connecting pipes is ensured to meet the test requirements.
The utility model discloses a test process as follows:
according to the attached drawing 3, when a low-temperature test of the floating ring seal assembly with one-way discharge and two-way discharge is carried out, a test device is mounted on a special support on a low-temperature seal test platform and is fastened by bolts with corresponding specifications, the coaxiality of a shaft of the test device and a high-speed shaft of a gearbox is adjusted, a coupling between the high-speed shaft of the gearbox and a stepped spindle 21 of the test device is mounted and is fastened by a nylon rope, and flexible connection is formed; the inlet and outlet pipeline and the sensor which are required by the connection test device comprise a bearing cooling inlet, a bearing cooling outlet, a test cavity 72 pressure measuring port, a first medium leakage amount detection port, a second medium leakage amount detection port, a leakage amount pressure measuring port and a leakage amount temperature measuring port; carrying out gas blowing on the test system, and after the blowing is finished; introducing low-pressure compressed air into the test device, and detecting the leakage of each sealing surface of the test device by using leakage detection liquid; and after the leakage detection is qualified, detecting the static normal-temperature gas leakage amount of the sealing assembly under the specified pressure. And after the normal-temperature gas leakage detection is finished, opening the medium inlet valve and the medium outlet valve, filling liquid nitrogen into the test device, precooling the test device, and detecting the static low-temperature gas leakage under the specified pressure of the floating ring sealing assembly when the temperature of the bearing cooling temperature measuring port 71 is lower than minus 180 ℃. When the temperatures of the two leakage temperature measuring ports of the front floating ring assembly and the rear floating ring assembly are lower than-190 ℃, the motor can be started, the pressure of a test cavity 72 of the test device is adjusted by a gas distribution table pressurization liquid nitrogen storage tank, an oil return pump and an oil supply pump of a gear box lubricating oil station are started, then the motor is started to drive the gear box and a stepped spindle 21 of the test device to run, the speed is slowly increased to a specified rotating speed according to test conditions, when the pressure of the seal cavity reaches the working pressure, the medium inlet flow of the seal cavity is regulated on the premise of keeping the pressure and the temperature of the seal inlet, the medium inlet flow, the pressure of the test cavity 72, the temperature of a bearing leakage port, the temperature of a bearing of the gear box, the vibration of the test device, the pressure of the leakage cavity of the floating ring seal assembly, the temperature of the leakage cavity, the leakage amount, the working rotating speed, the power of a test system and the like are measured, and whether the sealing performance of the seal assembly is qualified is judged by judging a leakage amount curve, and after the test time and times are reached, the oil pumps of the motor and the gear box lubricating oil station are closed, the static low-temperature gas leakage amount of the sealing assembly under the specified pressure is detected, the medium inlet valve is closed, and the test is finished.
When the low-temperature test of the floating ring sealing assembly with only one leakage is carried out, only two leakage detection ports, a temperature measurement port and a pressure measurement port on the shell I1 and the shell II2 are required to be plugged.
When the low-temperature test of the floating ring sealing assembly with only two leaks is carried out, only the detection port, the temperature measurement port and the pressure measurement port which are one leak on the shell I1 and the shell II2 are all plugged.
After the test device recovers to normal temperature, static normal-temperature gas leakage amount detection is carried out on the floating ring sealing assembly under specified pressure, then the test device is disassembled, the abrasion condition of the inner diameter of the engine floating ring assembly is measured and recorded, and all measurement parameter curves are obtained. The sealing performance and structural rationality of the seal assembly product are analyzed in terms of floating ring seal assembly test chamber 72 pressure, temperature and leakage, providing technical support and basis for improving various problems that arise in the seal assembly product design.
The utility model discloses accomplished batch random access test, running-in test and research nature test of liquid rocket engine floating ring sealing member (sealed like fuel, oxidant and the sealed floating ring of turbine) of many batches and kind, excellent in use effect. Reach according to many times experiment the utility model discloses test device rated parameter as follows: working rotating speed: 0-36000 r/min; test chamber 72 pressure: 4MPa (gauge pressure); working medium: liquid nitrogen; working temperature: -196 ℃ to-186 ℃. The parameters that the test apparatus can measure are as follows: working speed, test cavity 72 medium pressure, test cavity 72 temperature, test cavity 72 flow, leakage cavity leakage, leakage cavity pressure, leakage cavity temperature, test system power and inner diameter wear loss of the floating ring assembly. Many times of experiments show, the utility model discloses a test device is low temperature resistant and normal atmospheric temperature, and the machining precision is high, and structural design is reasonable, and device compatibility is good, stability is high under normal atmospheric temperature and low temperature high speed state.
Many times of experiments show, the utility model discloses the test device is low temperature resistant, and the machining precision is high, and is rational in infrastructure, and is experimental high-efficient, and device stability is strong under the high rotational speed state of low temperature.
It will be apparent to those skilled in the art that various modifications and variations can be made in the embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The specification and examples are exemplary only.

Claims (10)

1. The utility model provides a rocket engine is low temperature high rotational speed floating ring seal test device for turbo pump which characterized in that, this test device includes:
a housing comprising a housing I (1), a housing II (2), and a housing III (3);
the stepped spindle (21) is arranged inside the shell, one end of the stepped spindle (21) is fixed on the shell I (1) through a front bearing, and the other end of the stepped spindle (21) penetrates through the shell II (2) and is fixed on the shell III (3) through a rear bearing;
a front floating ring sealing component (47) and a rear floating ring sealing component (48) which are sleeved on the stepped spindle (21); the front floating ring sealing assembly (47) is fixed to the shell II (2) through a front floating ring shell, the rear floating ring sealing assembly (48) is fixed to the shell II (2) through a rear floating ring shell, and the front floating ring sealing assembly (47) and the rear floating ring sealing assembly (48) form a test cavity (72) in the shell II (2).
2. The test device for testing the sealing of the low-temperature high-speed floating ring for the turbopump of the rocket engine according to claim 1,
a first circular groove is formed in the front end face of the inner wall of the shell I (1), 3 first leather cups (49) are used for sealing in the first circular groove, the first leather cups (49) are fixed on the inner wall of the shell I (1) through first leather cup pressing covers (50), and a leakage cavity (51) is formed among the first circular groove, the shell I (1) and the front floating ring sealing assembly;
the rear floating ring sealing assembly (48), the rear end face of the inner wall of the shell II (2) and the shell III (3) enclose a secondary leakage cavity (52).
3. The test device for testing the sealing of the low-temperature high-speed floating ring for the turbopump of the rocket engine according to claim 2,
the shell I (1) is provided with 3 fourth through holes communicated with the first leakage cavity (51) and 3 fifth through holes communicated with the second leakage cavity (52);
and the shell II (2) is provided with 3 sixth through holes communicated with the first leakage cavity (51) and 3 seventh through holes communicated with the second leakage cavity (52).
4. The test device for the sealing of the low-temperature high-speed floating ring for the turbopump of the rocket engine according to claim 3, characterized in that the test device further comprises a front end cover (20) arranged on the housing I (1) and a rear end cover (6) arranged on the housing III (3).
5. The test device for the sealing of the low-temperature high-rotating-speed floating ring for the rocket engine turbo pump according to claim 4, wherein a second circular groove is formed in the rear end cover (6), 3 second leather cups (8) are used for sealing in the second circular groove, and the second leather cups (8) are fixed on the rear end cover (6) through second leather cup pressing covers (7).
6. The test device for testing the sealing of the low-temperature high-speed floating ring for the turbopump of the rocket engine according to claim 5,
a front bearing cooling cavity is formed between the front end cover (20) and the first leather cup (49); and a rear bearing cooling cavity is formed between the rear end cover (6) and the second leather cup.
7. The test device for testing the sealing of the low-temperature high-speed floating ring for the turbopump of the rocket engine according to claim 6,
an eighth through hole and a ninth through hole which are communicated with the front bearing cooling cavity are formed in the shell I (1), the eighth through hole is used for inputting a bearing cooling medium into the front bearing cooling cavity, and the ninth through hole is used for discharging the cooling medium in the front bearing cooling cavity;
a tenth through hole and an eleventh through hole which are communicated with the front bearing cooling cavity are formed in the front end cover (20), the tenth through hole is used for detecting the pressure value of the front bearing cooling cavity, and the eleventh through hole is used for detecting the temperature value of the front bearing cooling cavity;
and a twelfth through hole and a thirteenth through hole which are communicated with the rear bearing cooling cavity are formed in the shell III (3), the twelfth through hole is used for inputting bearing cooling media into the rear bearing cooling cavity, and the thirteenth through hole is used for discharging the cooling media in the rear bearing cooling cavity.
8. The test device for testing the sealing of the low-temperature high-speed floating ring for the turbopump of the rocket engine according to claim 6,
and a third circular groove is formed in the inner side wall of the rear end of the shell II (2), the third circular groove is sealed by using 3 third leather cups (19), and the rear bearing cooling cavity and the second leakage cavity (52) are separated by the third circular groove.
9. The test device for testing the sealing of the low-temperature high-speed floating ring for the turbopump of the rocket engine according to claim 4,
the other end of the stepped spindle (21) penetrates through the rear end cover (6), and the other end of the stepped spindle is connected with a speed increasing box arranged outside the shell through a flexible coupling.
10. The test device for testing the sealing of the low-temperature high-speed floating ring for the turbopump of the rocket engine according to claim 4,
sealing gaskets are arranged between the front floating ring sealing assembly (47) and the shell, between the rear floating ring sealing assembly (48) and the shell, between the front end cover (20) and the shell and between the rear end cover (6) and the shell; the sealing gasket material is soft aluminum subjected to annealing treatment;
the machining precision of the matching surface of the stepped main shaft (21) and the front bearing, the matching surface of the stepped main shaft (21) and the rear bearing, the matching surface of the stepped main shaft (21) and the front floating ring sealing assembly (47), and the matching surface of the stepped main shaft (21) and the rear floating ring sealing assembly (48) is 0.8 grade, and the form and position tolerance is less than 0.02 mm.
CN202022146741.4U 2020-09-27 2020-09-27 Low-temperature high-rotating-speed floating ring sealing test device for rocket engine turbine pump Active CN213775555U (en)

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Application Number Priority Date Filing Date Title
CN202022146741.4U CN213775555U (en) 2020-09-27 2020-09-27 Low-temperature high-rotating-speed floating ring sealing test device for rocket engine turbine pump

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115182829A (en) * 2022-07-15 2022-10-14 哈尔滨工业大学 Large-pressure-difference high-rotation-speed floating ring sealing test bench

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115182829A (en) * 2022-07-15 2022-10-14 哈尔滨工业大学 Large-pressure-difference high-rotation-speed floating ring sealing test bench

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