Device for testing gap pressure distribution of fixed gap cylindrical surface seal

Abstract

The invention discloses a fixed gap cylindrical surface sealing gap pressure distribution testing device, and belongs to the technical field of cylindrical surface sealing test. The sealing device comprises a sealing stator assembly, a sectioning shaft sleeve assembly, a shaft sleeve driving assembly and a mounting seat assembly, the sectioning shaft sleeve assembly and the shaft sleeve driving assembly are both arranged on the mounting seat assembly; the split shaft sleeve assembly comprises a split shaft sleeve and a shaft sleeve clamping assembly used for clamping the shaft sleeve. The shaft sleeve is rotatably arranged on the mounting seat assembly; the shaft sleeve is sleeved with the sealing stator assembly, and a sealing gap is formed between the sealing stator assembly and the shaft sleeve; the shaft sleeve is controlled by a shaft sleeve driving assembly to realize axial movement and rotation; the testing device further comprises a sensor used for measuring pressure at the inlet and outlet of the sealing gap and internal pressure. According to the invention, based on the structural design which is simple and convenient to mount and dismount, the accurate test of the omnibearing pressure distribution of the fixed gap cylindrical surface sealing gap is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of cylindrical sealing test, and in particular relates to a fixed-gap cylindrical sealing gap pressure distribution test device. Background Art

[0002] Fixed stator cylindrical gap seals, including labyrinth seals, honeycomb seals and hole-type damping seals, are commonly used sealing forms for steam turbines, gas turbines and various turbine machinery, with the advantages of simple structure, easy installation and high reliability. The main structure of the fixed stator cylindrical seal is a pair of seals consisting of a rotating shaft or sleeve as a sealing rotor and a sealing stator fixedly installed on a stationary housing. The main channel for medium leakage, i.e., the sealing gap, is formed between the inner surface of the sealing stator and the outer surface of the sealing rotor. The study of pressure distribution in the sealing gap is crucial to revealing the throttling and pressure reduction mechanism of the sealing structure and improving the flow resistance and leakage control ability of the sealing structure, and has a significant impact on the leakage characteristics and dynamic characteristics of the fixed stator cylindrical seal. In the actual application of cylindrical gap sealing, the intake and exhaust pressure of the seal can be tested by installing pressure sensors at the inlet and outlet of the cylindrical gap seal. However, due to the complexity of the sealing structure at the sealing gap, the existing fixed stator cylindrical seal test platform generally finds it difficult to test the sealing pressure in the cylindrical sealing gap, and cannot achieve accurate testing to obtain the all-round pressure distribution in the cylindrical sealing gap, which restricts the research on the influence of the pressure distribution of the cylindrical sealing gap. Summary of the invention

[0003] In order to solve the problem that the existing cylindrical gap sealing test platform is difficult to accurately test the omnidirectional pressure distribution in the sealing gap, the present invention provides a cylindrical sealing gap pressure distribution test device with convenient control and accurate testing. The technical solution adopted by the present invention is:

[0004] A fixed-gap cylindrical seal gap pressure distribution test device comprises a sealing stator assembly, a split-petal sleeve assembly, a sleeve drive assembly and a mounting seat assembly; the split-petal sleeve assembly and the sleeve drive assembly are both arranged on the mounting seat assembly; the split-petal sleeve assembly comprises a split sleeve and a sleeve clamping assembly for clamping the sleeve; the sleeve is rotatably arranged on the mounting seat assembly; the sealing stator assembly is sleeved on the sleeve, and a sealing gap is arranged between the sealing stator assembly and the sleeve; the sleeve is controlled by the sleeve drive assembly to realize axial movement and rotation;

[0005] The test device also includes sensors for measuring the pressure at the inlet and outlet of the sealing gap and the internal pressure.

[0006] Furthermore, the sleeve clamping assembly includes an outer conical ring and an inner conical ring. The outer conical ring is overlapped on the inner conical ring and fastened by fastening screws. During the fastening process, the axial spacing between the outer conical ring and the inner conical ring is reduced, and the conical matching structure on the inner side between the inner conical ring and the outer conical ring is used to apply a clamping radial force to the sleeve.

[0007] Furthermore, the sealing stator assembly includes a sealing stator sleeved on the shaft sleeve and a sealing cavity sleeved on the sealing stator, and the sealing cavity is provided with a second pressure sensor for detecting the pressure at the inlet and outlet of the sealing gap.

[0008] Furthermore, the mounting seat assembly includes a driving end sealing end cover, a free end sealing end cover and a vertical mounting plate; the shaft sleeve can be rotatably inserted into the driving end sealing end cover and the free end sealing end cover.

[0009] Furthermore, a sealing structure is provided between the driving end sealing end cover and the shaft sleeve, and between the free end sealing end cover and the shaft sleeve; an axial compression sleeve for axially compressing and sealing the stator is provided in the free end sealing end cover 42 .

[0010] Furthermore, the sealing stator is located between the driving end sealing end cover and the free end sealing end cover, and a first pressure chamber and a second pressure chamber are formed between its two ends and the corresponding sealing end covers respectively, and the first pressure chamber and the second pressure chamber are connected through a sealing gap; a vent hole connected to the first pressure chamber and the second pressure chamber is opened on the sealing cavity body.

[0011] Furthermore, the shaft sleeve driving assembly is arranged on the vertical mounting plate, and includes an axial displacement table for controlling the axial movement of the shaft sleeve and a rotation angle table for controlling the rotation of the shaft sleeve.

[0012] Furthermore, an interface seal is provided at the contact surface of the shaft sleeve split structure.

[0013] Furthermore, the interface seal includes sealing paper and sealant coated on the sealing paper.

[0014] Furthermore, the shaft sleeve is provided with at least one pressure measuring hole and a sensor mounting hole connected to the pressure measuring hole.

[0015] By adopting the above technology, compared with the prior art, the beneficial effects of the present invention are as follows:

[0016] 1) The device of the present invention constructs a cylindrical sealing gap scenario by providing a sealing stator assembly and a split sleeve assembly. Based on the split structural design of the sleeve, it is easy to install and disassemble the sensor. The sleeve clamping assembly provided in combination can apply a clamping radial force to the split sleeve, so that the split structures of the sleeve are more closely fitted.

[0017] 2) In the present invention, by setting the sleeve drive assembly, based on the axial displacement platform and the control sleeve motion control of the sleeve, the omnidirectional pressure distribution in the cylindrical sealing gap can be accurately tested and obtained;

[0018] 3) In the present invention, by opening a pressure measuring hole on the shaft sleeve and cooperating with a sensor, the pressure at the inlet and outlet of the sealing gap and the pressure inside the sealing gap can be accurately measured, thereby realizing efficient pressure testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic cross-sectional structure diagram of a cylindrical sealing gap pressure distribution testing device according to the first embodiment of the present invention;

[0020] Figure 2 It is a three-dimensional structural schematic diagram of a cylindrical sealing gap pressure distribution testing device according to the first embodiment of the present invention;

[0021] Figure 3 It is a schematic diagram of the three-dimensional structure of the petal sleeve assembly according to the first embodiment of the present invention;

[0022] Figure 4 It is a schematic diagram of the installation position of the first pressure sensor on the split-petal sleeve of the first embodiment of the present invention;

[0023] Figure 5 It is a schematic cross-sectional structure diagram of a cylindrical sealing gap pressure distribution test device when the first pressure sensor of the first embodiment of the present invention is in the rightmost axial state;

[0024] Figure 6 It is a schematic cross-sectional structure diagram of a cylindrical sealing gap pressure distribution testing device when the first pressure sensor of the first embodiment of the present invention is in a state of circumferential rotation of 180°;

[0025] Figure 7 Schematic diagram of the split-petal shaft sleeve interface sealing structure of an embodiment of the present invention;

[0026] Figure 8 is a schematic diagram of a three-dimensional cross-sectional structure of a shaft sleeve clamping assembly according to an embodiment of the present invention;

[0027] Fig. 9 It is a three-dimensional structural diagram of the shaft sleeve drive assembly and the petal shaft sleeve assembly of the first embodiment of the present invention;

[0028] Fig.10 is a schematic cross-sectional view of the axial compression structure of the sealing stator according to an embodiment of the present invention;

[0029] Fig.11 It is a schematic cross-sectional structure diagram of a cylindrical sealing gap pressure distribution testing device according to the second embodiment of the present invention. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments of the specification. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] On the contrary, the present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention as defined by the claims. Further, in order to make the public have a better understanding of the present invention, some specific details are described in detail in the detailed description of the present invention below. Those skilled in the art can fully understand the present invention without the description of these details.

[0032] Embodiment 1:

[0033] Reference Figure 1 , 2 A fixed gap cylindrical seal gap pressure distribution test device includes a seal stator assembly 1, a petal sleeve assembly 2, a sleeve drive assembly 3 and a mounting seat assembly 4. The seal stator assembly 1 includes a seal cavity 11 and a seal stator 12, the outer surface of the seal stator 12 is in contact with the inner surface of the seal cavity 11, and the seal cavity 11 and the seal stator 12 always maintain a concentric state.

[0034] Reference Figure 3-6 The split sleeve assembly 2 includes a sleeve 21, a sleeve clamping assembly 22 and a first pressure sensor 23. The sleeve 21 is composed of a first sleeve 211 and a second sleeve 212 and is radially clamped by the sleeve clamping assembly 22. A pressure sensor mounting hole 25 is provided on the inner surface of the sleeve 21, and a plurality of pressure measuring holes 26 are arranged staggered in the circumferential direction and the axial direction on the outer surface of the sleeve 21. The first pressure sensor 23 is installed on the inner surface of the sleeve 21, and the first pressure sensor 23 is installed in the pressure sensor mounting hole 25. The pressure sensor mounting hole 25 is connected to the pressure measuring hole 26. A sealing gap 51 is provided between the outer surface of the sleeve 21 and the inner surface of the sealing stator 12 in the radial direction. One axial side of the sealing stator 12 is the high-pressure medium side, and the other side is the low-pressure medium side. Under the action of the pressure difference, the sealing medium leaks from the high-pressure medium side to the low-pressure medium side through the sealing gap 51. The pressure measuring hole 26 is connected to the sealing gap 51. At this time, the sealing pressure in the sealing gap 51 can be directly measured by the first pressure sensor 23. The adjacent first pressure sensors 23, pressure sensor mounting holes 25 and pressure measuring holes 26 are arranged at an angle of 180° and are equidistant, corresponding to the positions of 0, 1 / 4, 1 / 2 and 3 / 4 of the axial length of the sealing stator 12, respectively. When the axial displacement table 31 axially moves 1 / 4 of the axial length of the sealing stator 12 and the rotation angle table 33 rotates 180° circumferentially at different axial positions, the all-round pressure distribution in the cylindrical sealing gap 51 can be obtained by testing.

[0035] Reference Figure 7 The sleeve 21 includes a first-lobe sleeve 211 and a second-lobe sleeve 212. The plane of the first-lobe sleeve 211 fits with the plane of the second-lobe sleeve 212. To ensure good sealing performance at the contact surface, the two planes should be processed as smoothly as possible. At the same time, a petal interface seal 24 is provided between the first-lobe sleeve 211 and the second-lobe sleeve 212. The petal interface seal 24 is a composition of a sealant 241 and an ultra-thin sealing paper 242. The petal interface seal 24 not only has a good sealing effect, but also makes it convenient to open the sleeve 21 for installation of the first pressure sensor 23.

[0036] Reference Figure 8 The sleeve clamping assembly 22 is composed of an outer conical ring 221, an inner conical ring 222 and a fastening screw 223. The outer conical ring 221 is overlapped on the inner conical ring 222, and the two are connected by the fastening screw 223. By tightening the fastening screw 223, the axial distance between the outer conical ring 221 and the inner conical ring 222 can be reduced. The conical matching structure on the inner side between the inner conical ring 222 and the outer conical ring 221 is used to apply a clamping radial force to the sleeve (21). Under the action of the radial force, the plane of the first petal sleeve 211 and the plane of the second petal sleeve 212 fit more closely.

[0037] Reference Fig. 9 The sleeve drive assembly 3 includes an axial displacement table 31, an adapter plate 32, a rotation angle table 33 and a sleeve adapter seat 34 which are fixedly connected in sequence. The axial displacement table 31 and the rotation angle table 33 are fixedly connected via the adapter plate 32. To realize the axial movement and circumferential rotation of the sleeve 21, the rotation angle table 33 and the sleeve adapter seat 34 are fixedly connected. The sleeve 21 is mounted on the sleeve adapter seat 34. The axial displacement and circumferential rotation angle of the sleeve 21 are driven by the axial displacement table 31 and the rotation angle table 33 respectively. The axial displacement table 31 is fixed on the vertical mounting plate 43.

[0038] Reference Fig.10The mounting seat assembly 4 includes a driving end sealing end cover 41 and a free end sealing end cover 42. The driving end sealing end cover 41 and the free end sealing end cover 42 are fixed on the horizontal mounting plate 44, and the sealing cavity 11 is fixedly installed at the axial distance between the two sealing end covers. The shaft sleeve 21 passes through the inner hole 411 of the driving end sealing end cover and the inner hole 421 of the free end sealing end cover. In order to ensure reliable sealing between the driving end sealing end cover 41 and the shaft sleeve 21 and between the free end sealing end cover 42 and the shaft sleeve 21, a first auxiliary sealing ring 412 is provided between the driving end sealing end cover 41 and the shaft sleeve 21, and a second auxiliary sealing ring 422 is provided between the free end sealing end cover 42 and the shaft sleeve 21. The sealing cavity 11 is provided with a first air hole 111 and a second air hole 112, and a second pressure sensor 14 is installed on the sealing cavity 11. The first pressure chamber 52 is between the driving end sealing end cover 41 and the sealing stator 12, which is the high-pressure medium side, and the second pressure chamber 53 is between the free end sealing end cover 42 and the sealing stator 12, which is the low-pressure medium side. The first pressure chamber 52 is connected to the first air hole 111, and the second pressure chamber 53 is connected to the second air hole 112. The first pressure chamber 52 and the second pressure chamber 53 are connected through the sealing gap 51. The second pressure sensor 14 is used to measure the inlet and outlet pressures before and after the sealing gap 51. The free end sealing end cover 42 is provided with an axial compression sleeve 13 for axially compressing the sealing stator 12, and the axial compression sleeve 13 is provided with an air hole connected to the second air hole 112 for gas discharge.

[0039] Embodiment 2:

[0040] Reference Fig.11 The difference between the embodiment 1 and the embodiment 1 is that only one pressure measuring hole 26 is provided on the sleeve 21, and a first pressure sensor 23 is installed on the inner surface of the sleeve 21. The first pressure sensor 23 is installed in the pressure sensor mounting hole 25. The pressure sensor mounting hole 25 is connected with the pressure measuring hole 26, and is used to directly measure the sealing pressure in the sealing gap 51. In order to obtain the all-round pressure distribution in the cylindrical sealing gap 51 through testing, the axial displacement platform 31 needs to axially move a complete axial length of the sealing stator 12 and the rotation angle platform 33 needs to rotate 180° circumferentially at different axial positions. The rest of the structure and principle are the same as those of the embodiment 1.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A fixed gap cylindrical seal gap pressure distribution test device, characterized in that: The invention comprises a sealing stator assembly (1), a split-petal sleeve assembly (2), a sleeve drive assembly (3) and a mounting seat assembly (4); the split-petal sleeve assembly (2) and the sleeve drive assembly (3) are both arranged on the mounting seat assembly (4); the split-petal sleeve assembly (2) comprises a split sleeve (21) and a sleeve clamping assembly (22) for clamping the sleeve (21); the sleeve (21) is rotatably arranged on the mounting seat assembly (4); the sealing stator assembly (1) is sleeved on the sleeve (21), and a sealing gap (51) is arranged between the sealing stator assembly (1) and the sleeve (21); the sleeve (21) is controlled by the sleeve drive assembly (3) to achieve axial movement and rotation; The testing device also includes a sensor for measuring the pressure at the inlet and outlet of the sealing gap (51) and the internal pressure.

2. A fixed gap cylindrical seal gap pressure distribution test device according to claim 1, characterized in that: The shaft sleeve clamping assembly (22) comprises an outer conical ring (221) and an inner conical ring (222); the outer conical ring (221) is overlapped on the inner conical ring (222) and is fastened by a fastening screw (223); during the fastening process, the axial distance between the outer conical ring (221) and the inner conical ring (222) is reduced, and a clamping radial force is applied to the shaft sleeve (21) by utilizing the conical matching structure on the inner side between the inner conical ring (222) and the outer conical ring (221).

3. A fixed gap cylindrical seal gap pressure distribution test device according to claim 2, characterized in that: The sealing stator assembly (1) comprises a sealing stator (12) sleeved on a shaft sleeve (21) and a sealing cavity (11) sleeved on the sealing stator (12), wherein the sealing cavity (11) is provided with a second pressure sensor (14) for detecting the pressure at the inlet and outlet of the sealing gap (51).

4. A fixed gap cylindrical seal gap pressure distribution test device according to claim 3, characterized in that: The mounting seat assembly (4) comprises a driving end sealing end cover (41), a free end sealing end cover (42) and a vertical mounting plate (43); the shaft sleeve (21) is rotatably inserted into the driving end sealing end cover (41) and the free end sealing end cover (42).

5. A fixed gap cylindrical seal gap pressure distribution test device according to claim 4, characterized in that: A sealing structure is provided between the driving end sealing end cover (41) and the shaft sleeve (21), and between the free end sealing end cover (42) and the shaft sleeve (21); and an axial compression sleeve (13) for axially compressing and sealing the stator (12) is provided in the free end sealing end cover 42.

6. A fixed gap cylindrical seal gap pressure distribution test device according to claim 4, characterized in that: The sealing stator (12) is located between the driving end sealing end cover (41) and the free end sealing end cover (42), and a first pressure chamber (52) and a second pressure chamber (53) are formed between the two ends and the corresponding sealing end covers, respectively. The first pressure chamber (52) and the second pressure chamber (53) are connected via a sealing gap (51); and a vent hole connected to the first pressure chamber (52) and the second pressure chamber (53) is provided on the sealing cavity body (11).

7. The fixed gap cylindrical seal gap pressure distribution test device according to claim 4, characterized in that: The shaft sleeve driving assembly (3) is arranged on a vertical mounting plate (43), and comprises an axial displacement platform (31) for controlling the axial movement of the shaft sleeve (21) and a rotation angle platform (33) for controlling the rotation of the shaft sleeve (21).

8. The fixed gap cylindrical seal gap pressure distribution test device according to claim 1, characterized in that: An interface seal (24) is provided at the contact surface of the shaft sleeve (21) split structure.

9. A fixed gap cylindrical seal gap pressure distribution test device according to claim 8, characterized in that: The interface seal (24) comprises a sealing paper (242) and a sealing glue (241) coated on the sealing paper (242).

10. The fixed gap cylindrical seal gap pressure distribution test device according to claim 1, characterized in that: The shaft sleeve (21) is provided with at least one pressure measuring hole (26) and a sensor mounting hole (25) communicating with the pressure measuring hole (26).

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