CN116428363A - Floating ring sealing structure with V-shaped micro-texture and sealing runway - Google Patents

Floating ring sealing structure with V-shaped micro-texture and sealing runway Download PDF

Info

Publication number
CN116428363A
CN116428363A CN202310437365.XA CN202310437365A CN116428363A CN 116428363 A CN116428363 A CN 116428363A CN 202310437365 A CN202310437365 A CN 202310437365A CN 116428363 A CN116428363 A CN 116428363A
Authority
CN
China
Prior art keywords
texture
sealing
micro
arrangement
shaped micro
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202310437365.XA
Other languages
Chinese (zh)
Inventor
赵欢
樊汝凤
孙丹
任国哲
温帅方
徐文峰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shenyang Aerospace University
Original Assignee
Shenyang Aerospace University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shenyang Aerospace University filed Critical Shenyang Aerospace University
Priority to CN202310437365.XA priority Critical patent/CN116428363A/en
Publication of CN116428363A publication Critical patent/CN116428363A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16J—PISTONS; CYLINDERS; SEALINGS
    • F16J15/00—Sealings
    • F16J15/16—Sealings between relatively-moving surfaces
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C17/00—Sliding-contact bearings for exclusively rotary movement
    • F16C17/02—Sliding-contact bearings for exclusively rotary movement for radial load only
    • F16C17/026—Sliding-contact bearings for exclusively rotary movement for radial load only with helical grooves in the bearing surface to generate hydrodynamic pressure, e.g. herringbone grooves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
    • F16C33/02—Parts of sliding-contact bearings
    • F16C33/04—Brasses; Bushes; Linings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16J—PISTONS; CYLINDERS; SEALINGS
    • F16J15/00—Sealings
    • F16J15/16—Sealings between relatively-moving surfaces
    • F16J15/164—Sealings between relatively-moving surfaces the sealing action depending on movements; pressure difference, temperature or presence of leaking fluid
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16J—PISTONS; CYLINDERS; SEALINGS
    • F16J15/00—Sealings
    • F16J15/16—Sealings between relatively-moving surfaces
    • F16J15/40—Sealings between relatively-moving surfaces by means of fluid

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Sealing (AREA)
  • Sealing Devices (AREA)
  • Sealing Using Fluids, Sealing Without Contact, And Removal Of Oil (AREA)

Abstract

The invention discloses a floating ring sealing structure with V-shaped micro-texture and a sealing runway, wherein the floating ring structure comprises: the rotor, sealing seat and floating ring seal assembly, floating ring seal assembly includes sealing runway and sealing ring, sealing runway fixed cover is established on the rotor, the sealing ring is installed in sealing seat and the periphery of sealing runway is located to the cooperation cover, multiunit V-arrangement micro-texture has evenly been seted up along its circumference to sealing runway's periphery, the V-arrangement micro-texture includes left chute and right chute, the front end intercommunication of left chute and right chute forms the tip of V-arrangement micro-texture, the afterbody of the little texture of rear end formation V-arrangement, the tip of the little texture of V-arrangement is towards the direction of rotation of rotor, and the degree of depth of the little texture of V-arrangement reduces or stepwise reduction along the direction of its tip to afterbody gradually. The floating ring sealing structure and the sealing runway with the V-shaped micro-texture have the advantages of being simple in structure, capable of remarkably enhancing dynamic pressure effect of sealing fluid of the floating ring, reducing abrasion degree of the sealing ring and prolonging service life of the sealing component.

Description

Floating ring sealing structure with V-shaped micro-texture and sealing runway
Technical Field
The invention relates to the field of aeroengine bearing cavity sealing, and particularly provides a floating ring sealing structure with V-shaped micro-textures and a sealing runway.
Background
The seal is widely applied to turbomachinery such as aeroengines and plays a key role in reducing leakage of working medium. However, in the starting-up or rotor speed-changing process, the sealing ring is easy to contact with the rotor, namely, the phenomenon that the sealing ring is not centered and cannot float easily occurs, so that the sealing gap is uneven, the floating ring is abnormally worn, the sealing effect is invalid, and the sealing service life of the floating ring is greatly reduced. Research shows that the micro-texture is formed on the surface of the inner diameter of the floating ring seal, so that the fluid dynamic pressure effect can be generated, the contact load of the sealing surface is reduced, the service life of the seal assembly is prolonged, and the leakage rate of the seal ring under non-contact operation is minimized. However, the traditional integral floating ring seal with the rectangular micro-texture of the inner surface of the floating ring cannot ensure that the sealing ring is completely floating due to the dynamic pressure effect, so that the failure caused by abrasion failure of the sealing surface cannot be fundamentally solved.
Therefore, how to further improve the floating ring sealing structure so as to effectively enhance the hydrodynamic pressure effect, ensure the sealing ring to float up quickly and completely, reduce the abrasion of the sealing ring, and become a problem to be solved urgently.
Disclosure of Invention
In view of the above, the invention aims to provide a floating ring sealing structure with V-shaped micro-texture and a sealing runway, so as to solve the problems that a sealing ring cannot float during starting up or rotor speed change, and is extremely easy to rub against a rotor.
In one aspect, the present invention provides a floating ring seal structure with V-shaped micro-texture, comprising: rotor, sealing seat and floating ring seal assembly, wherein, floating ring seal assembly includes sealing runway and sealing ring, sealing runway fixed cover is established on the rotor, the sealing ring install in the sealing seat and the cooperation cover is located sealing runway's periphery, multiunit V-arrangement micro-texture has evenly been seted up along its circumference to sealing runway's periphery, V-arrangement micro-texture includes left chute and right chute that the symmetry set up, the front end intercommunication of left chute and right chute forms the tip of V-arrangement micro-texture, the rear end of left chute and right chute forms the afterbody of V-arrangement micro-texture, the tip of V-arrangement micro-texture is towards the direction of rotation of rotor, just the degree of depth of V-arrangement micro-texture reduces or stepwise reduces along the direction of its tip to afterbody gradually.
Preferably, each set of V-shaped micro-textures comprises a plurality of V-shaped micro-textures arranged coaxially and at equal intervals.
Further preferably, the width of the plurality of V-shaped micro-textures in each set of V-shaped micro-textures increases in the direction of rotation of the rotor, and the lengths of the left chute and the right chute increase in length.
Further preferably, each group of V-shaped micro-textures comprises 3V-shaped micro-textures, the distance between every two adjacent V-shaped micro-textures is 2-3 mm, the widths of the 3V-shaped micro-textures are 2-2.5 mm, 1.5-2 mm and 1-1.5 mm in sequence, the lengths of the left chute and the right chute are 6 mm-8 mm,4 mm-6 mm and 2 mm-4 mm in sequence, the maximum depth of the tip is 15-20 um, the minimum depth of the tail is 0-5 um, and the included angle alpha between the left chute and the right chute of the 3V-shaped micro-textures is equal and is 110-150 degrees.
Further preferably, the V-shaped micro-texture is provided at an axial center position of the seal ring.
Further preferably, the sealing ring is a complete ring or is composed of a plurality of ring petals.
Further preferably, an axial spring groove is formed in the end face of the high-pressure inlet of the sealing ring, an axial compression spring is mounted in the axial spring accommodating groove in a matched mode, and the axial compression spring abuts against a baffle plate fixedly arranged and is used for pressing the sealing ring onto the sealing seat.
Further preferably, a circlip is provided on the outside of the baffle.
The invention also provides a sealing runway with the V-shaped micro-textures, wherein a plurality of groups of V-shaped micro-textures are uniformly arranged on the periphery of the sealing runway along the circumferential direction of the sealing runway, the V-shaped micro-textures comprise a left chute and a right chute which are symmetrically arranged, the front ends of the left chute and the right chute are communicated to form tip parts of the V-shaped micro-textures, the rear ends of the left chute and the right chute form tail parts of the V-shaped micro-textures, the tip parts of the V-shaped micro-textures face the rotating direction of a rotor for installing the sealing runway, and the depth of the V-shaped micro-textures gradually decreases or stepwise decreases along the direction from the tip parts to the tail parts.
The floating ring sealing structure with the V-shaped micro-texture and the sealing runway provided by the invention have the advantages of simple structure and controllable cost, can obviously enhance the dynamic pressure effect of the floating ring sealing fluid, reduce the abrasion degree of the sealing ring and prolong the service life of the sealing component.
Drawings
The invention will be described in further detail with reference to the accompanying drawings and embodiments:
FIG. 1 is an axial cross-sectional view of a floating ring seal structure with V-shaped micro-texture provided by the invention;
FIG. 2 is a circumferentially expanded view of the sealing track;
FIG. 3 is a radial cross-sectional view of the rotor and floating ring seal assembly.
Detailed Description
The invention will be further explained below in connection with specific embodiments, but is not limited to the invention.
As shown in fig. 1 to 3, the present invention provides a floating ring seal structure with V-shaped micro-texture, comprising: rotor 1, sealing seat 2 and floating ring seal assembly, wherein, floating ring seal assembly includes sealing runway 3 and sealing ring 4, sealing runway 3 fixed cover is established on the rotor 1, sealing ring 4 install in sealing seat 2 and cooperation cover are located sealing runway 3's periphery, multiunit V-arrangement micro-texture 31 has evenly been seted up along its circumference to sealing runway 3's periphery, V-arrangement micro-texture 31 includes left chute 311 and right chute 312 that the symmetry set up, the front end intercommunication of left chute 311 and right chute 312 forms the tip of V-arrangement micro-texture 31, the rear end of left chute 311 and right chute 312 forms the afterbody of V-arrangement micro-texture 31, the tip of V-arrangement micro-texture 31 is towards rotor 1's direction of rotation, just the degree of depth of V-arrangement micro-texture 31 reduces or stepwise along its direction towards the afterbody gradually.
The floating ring sealing structure with the V-shaped micro-textures is characterized in that a plurality of groups of V-shaped micro-textures are arranged on a sealing runway, when a rotor rotates, gas at a high pressure side can be introduced into a sealing gap between a sealing ring and the sealing runway under the action of pressure difference, meanwhile, under the high-speed shearing driving of the rotor, a large amount of gas can be extruded into the V-shaped micro-textures, and enters a small space (a deep region of the V-shaped micro-textures) from a large space (a deep region of the V-shaped micro-textures) along with the rotation of the rotor, so that a local high-pressure region is formed, a remarkable hydrodynamic effect is generated, the rapid floating of the sealing ring is ensured, the contact area between the inner peripheral surface of the sealing ring and the outer peripheral surface of the sealing runway is further reduced, the wearing degree of the sealing ring is reduced, the applicable working condition of the sealing ring is widened, the service life of the sealing assembly is prolonged, in addition, the airflow flow area is increased, the pressure is generated, the gas at the high pressure side enters the V-shaped micro-textures to play a lubricating role on the sealing surface, the circumferential direction of the sealing surface is reduced, the wearing degree of the airflow resistance is increased, the local hydrodynamic effect is reduced, and the service life of the dynamic pressure is prolonged.
As an improvement of the technical scheme, as shown in fig. 2 and 3, each group of V-shaped micro-textures 31 comprises a plurality of V-shaped micro-textures 31 which are coaxially and equally spaced, and the V-shaped micro-textures are used for increasing the complexity of the flow field in the axial direction of the seal, so that the energy dissipation of the flow field is increased, and the purpose of reducing the leakage is achieved.
As an improvement of the technical solution, as shown in fig. 2 and 3, along the rotation direction of the rotor 1, the widths of the V-shaped micro-textures 31 in each group of V-shaped micro-textures 31 are increased gradually, and the lengths of the left chute 311 and the right chute 312 are increased gradually, so as to increase the circumferential flow velocity in the sealing gap gradually, and further enhance the hydrodynamic effect.
As an improvement of the technical scheme, as shown in fig. 2 and 3, each group of V-shaped micro-textures 31 comprises 3V-shaped micro-textures 31, the distance between adjacent V-shaped micro-textures 31 is 2-3 mm, the widths of the 3V-shaped micro-textures 31 are 2-2.5 mm, 1.5-2 mm and 1-1.5 mm in sequence, the lengths of the left chute 311 and the right chute 312 are 6-8 mm, 4-6 mm and 2 mm-4 mm in sequence, the maximum depth of the tip is 15-20 um, the minimum depth of the tail is 0-5 um, the included angle alpha between the left chute 311 and the right chute 312 of the 3V-shaped micro-textures 31 is equal and is 110-150 degrees, and the design can enable airflow to form a local high-pressure area from a large gap to a small gap, generate fluid dynamic pressure effect, reduce abrasion of a graphite ring and prolong the service life of the graphite ring.
As an improvement of the technical scheme, as shown in fig. 1, the V-shaped micro-texture 31 is disposed at the axial center of the sealing ring 4, so as to ensure the airflow velocity and achieve the effect of enhancing the hydrodynamic effect.
As an improvement of the technical scheme, the sealing ring 4 is a whole ring or consists of a plurality of ring petals, and when the sealing ring consists of the plurality of ring petals, as shown in fig. 1, the ring petals are clamped by a circumferential spring 8 arranged on the periphery of the ring petals.
As an improvement of the technical scheme, as shown in fig. 1, an axial spring groove is formed in the end face of the high-pressure inlet of the sealing ring 4, an axial compression spring 5 is installed in the axial spring accommodating groove in a matched mode, and the axial compression spring 5 abuts against a baffle 6 fixedly arranged and is used for pressing the sealing ring 4 on the sealing seat 1.
As an improvement of the technical scheme, as shown in fig. 1, a circlip 7 is arranged on the outer side of the baffle 6.
The invention also provides a sealing runway with V-shaped micro-textures, as shown in fig. 2, a plurality of groups of V-shaped micro-textures 31 are uniformly arranged on the periphery of the sealing runway 3 along the circumferential direction of the sealing runway, the V-shaped micro-textures 31 comprise a left chute 311 and a right chute 312 which are symmetrically arranged, the front ends of the left chute 311 and the right chute 312 are communicated to form tip parts of the V-shaped micro-textures 31, the rear ends of the left chute 311 and the right chute 312 form tail parts of the V-shaped micro-textures 31, the tip parts of the V-shaped micro-textures 31 face the rotating direction of a rotor 1 for mounting the sealing runway 3, and the depth of the V-shaped micro-textures 31 is gradually reduced or stepwise reduced along the direction from the tip parts to the tail parts.
When the floating ring sealing structure with the V-shaped micro-texture can be matched with the rotor, the sealing ring and the sealing seat for use (shown in figure 1), when the rotor rotates, gas at a high pressure side can be introduced into a sealing gap between the sealing ring and the sealing runway under the action of pressure difference, and simultaneously, a large amount of gas can be extruded into the V-shaped micro-texture under the high-speed shearing driving of the rotor, and enters a small space (a deep shallow depth area of the V-shaped micro-texture) from a large space (a deep depth area of the V-shaped micro-texture) along with the rotation of the rotor, so that a local high-pressure area is formed, a remarkable hydrodynamic effect is generated, the rapid floating of the sealing ring is ensured, the contact area between the inner peripheral surface of the sealing ring and the outer peripheral surface of the sealing runway is further reduced, the abrasion degree of the sealing ring is reduced, the applicable working condition of the sealing ring is widened, and the service life of the sealing assembly is prolonged.
The embodiments of the invention have been written in an incremental manner with emphasis on the differences between the various embodiments being placed upon which similar parts may be seen.
The embodiments of the present invention have been described in detail with reference to the drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the spirit of the present invention.

Claims (9)

1. Floating ring seal structure with V-arrangement micro-texture, its characterized in that includes: rotor (1), sealing seat (2) and floating ring seal assembly, wherein, floating ring seal assembly includes sealed runway (3) and sealing ring (4), sealed runway (3) fixed cover is established on rotor (1), sealing ring (4) install in sealed seat (2) and cooperation cover are located the periphery of sealed runway (3), multiunit V-arrangement micro-texture (31) have evenly been seted up along its circumference to sealed runway (3) periphery, V-arrangement micro-texture (31) including left chute (311) and right chute (312) that the symmetry set up, the front end intercommunication of left chute (311) and right chute (312) forms the tip of V-arrangement micro-texture (31), the rear end of left chute (311) and right chute (312) forms the afterbody of V-arrangement micro-texture (31), V-arrangement micro-texture (31) orientation the direction of rotation of rotor (1), just the degree of depth of V-arrangement micro-texture (31) reduces or reduces to its tip gradually along the tip.
2. The floating ring seal structure with V-shaped micro-texture of claim 1, wherein: each group of V-shaped micro-textures (31) comprises a plurality of V-shaped micro-textures (31) which are coaxially and equally spaced.
3. The floating ring seal structure with V-shaped micro-texture of claim 2, wherein: the widths of the plurality of V-shaped micro-textures (31) in each group of V-shaped micro-textures (31) are increased along the rotation direction of the rotor (1), and the lengths of the left chute (311) and the right chute (312) are increased.
4. A floating ring seal structure with V-shaped micro-texture as claimed in claim 3, wherein: each group of V-shaped micro-textures (31) comprises 3V-shaped micro-textures (31), the distance between every two adjacent V-shaped micro-textures (31) is 2-3 mm, the widths of the 3V-shaped micro-textures (31) are 2-2.5 mm, 1.5-2 mm and 1-1.5 mm in sequence, the lengths of the left chute (311) and the right chute (312) are 6-8 mm, 4-6 mm,2 mm-4 mm, the maximum depth of the tip is 15-20 um, the minimum depth of the tail is 0-5 um, and the included angle alpha of the left chute (311) and the right chute (312) of the 3V-shaped micro-textures (31) is equal and is 110-150 degrees.
5. The floating ring seal structure with V-shaped micro-texture of claim 1, wherein: the V-shaped micro-texture (31) is arranged at the axial center position of the sealing ring (4).
6. The floating ring seal structure with V-shaped micro-texture of claim 1, wherein: the sealing ring (4) is a whole ring or consists of a plurality of ring petals.
7. The floating ring seal structure with V-shaped micro-texture of claim 1, wherein: the high-pressure inlet end face of the sealing ring (4) is provided with an axial spring groove, an axial compression spring (5) is installed in the axial spring accommodating groove in a matched mode, and the axial compression spring (5) is abutted against a baffle plate (6) fixedly arranged and used for tightly pressing the sealing ring (4) on the sealing seat (1).
8. The floating ring seal structure with V-shaped micro-texture of claim 1, wherein: and an elastic retainer ring (7) is arranged on the outer side of the baffle plate (6).
9. Sealing runway with V-arrangement micro-texture, its characterized in that: the periphery of sealed runway (3) has evenly offered multiunit V-arrangement micro-texture (31) along its circumference, the little texture (31) of V-arrangement is including left chute (311) and right chute (312) that the symmetry set up, the front end intercommunication of left chute (311) and right chute (312) forms the tip of little texture (31) of V-arrangement, the rear end formation of left chute (311) and right chute (312) the afterbody of little texture (31) of V-arrangement, the tip orientation of little texture (31) of V-arrangement is installed the direction of rotation of rotor (1) of sealed runway (3), just the degree of depth of little texture (31) of V-arrangement reduces or stepwise reduces along the direction of its tip to the afterbody gradually.
CN202310437365.XA 2023-04-23 2023-04-23 Floating ring sealing structure with V-shaped micro-texture and sealing runway Pending CN116428363A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310437365.XA CN116428363A (en) 2023-04-23 2023-04-23 Floating ring sealing structure with V-shaped micro-texture and sealing runway

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310437365.XA CN116428363A (en) 2023-04-23 2023-04-23 Floating ring sealing structure with V-shaped micro-texture and sealing runway

Publications (1)

Publication Number Publication Date
CN116428363A true CN116428363A (en) 2023-07-14

Family

ID=87090689

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310437365.XA Pending CN116428363A (en) 2023-04-23 2023-04-23 Floating ring sealing structure with V-shaped micro-texture and sealing runway

Country Status (1)

Country Link
CN (1) CN116428363A (en)

Similar Documents

Publication Publication Date Title
US6145843A (en) Hydrodynamic lift seal for use with compressible fluids
EP0473018B1 (en) Compliant finger seal
US7461847B2 (en) Self centering, floating brush seal assembly
EP1116906A2 (en) A seal arrangement
JP2001012610A (en) Face seal structure
CN112161062B (en) Combined sealing structure
CN105221580B (en) bearing
CN113028067B (en) Self-adaptive labyrinth sealing device for high-speed shaft
CN111927635B (en) Graphite sealing structure with twill dynamic pressure groove
CN111998075B (en) Sealing structure suitable for engine bearing cavity
CN110439631B (en) Labyrinth sealing structure capable of controlling active clearance
CN116428363A (en) Floating ring sealing structure with V-shaped micro-texture and sealing runway
CN113090337A (en) Reverse shaft sealing device for double-rotor aircraft engine
CN111237163A (en) Piston ring sealing system with long service life
CN111927634B (en) Bearing chamber non-contact graphite sealing structure
CN113090341B (en) Fingertip sealing device capable of adapting to bidirectional rotation of rotor
US4302019A (en) Labyrinthine mechanical seal
CN114321389A (en) Balance type piston ring sealing device
CN114215916A (en) Air film sealing structure for main bearing cavity of aero-engine
CN111927633B (en) Graphite sealing structure with anti-fishbone dynamic pressure groove
CN111306304A (en) Rotary-vane type high-temperature high-pressure gas (liquid) elastic contact dynamic sealing device and preparation method
CN110863868A (en) Mechanical non-contact end face sealing system for gas turbine bearing cavity
CN216158130U (en) Clutch bearing sealing structure
CN218760577U (en) Wear-resistant water seal for internal combustion engine
CN111350551B (en) Be used for flexible cylinder air film seal structure between birotor axle

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination