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CN-122007805-A - Sealing end face preparation method and sealing ring

CN122007805ACN 122007805 ACN122007805 ACN 122007805ACN-122007805-A

Abstract

The invention provides a preparation method of a sealing end face and a sealing ring, which comprises the following steps of S1, processing a plurality of micro grooves which are arranged along the circumferential direction on the end face of a substrate of the sealing ring; the method comprises the steps of S2, preparing a plurality of diamond blocks, respectively placing the diamond blocks into a plurality of micro grooves, fixing the diamond blocks and a matrix by adopting an active brazing process, ensuring that the upper end face of each diamond protrudes out of the end face of the matrix, S3, uniformly piling and injecting a metal coating on the surfaces of the diamond blocks and the matrix which are fixed by brazing, wherein the thickness of the metal coating is higher than the protruding height of the diamond blocks, and S4, grinding and polishing the end face of the matrix where the metal coating is piled until the top ends of all the diamond blocks are exposed, and enabling the whole end face to reach mirror-surface finish. The preparation method of the sealing end face and the sealing ring provided by the invention have excellent physical and chemical properties, are low in cost and reliable in batch manufacturing, and can be used for adapting large-size sealing rings.

Inventors

  • CHEN KAN
  • JIANG MIN
  • LI ZHONGLIN

Assignees

  • 宁波天工流体科技股份有限公司

Dates

Publication Date
20260512
Application Date
20260127

Claims (10)

  1. 1. The preparation method of the sealing end face is characterized by comprising the following steps of: S1, processing a plurality of prearranged micro grooves (2) which are arrayed along the circumferential direction on the end surface of a substrate (1) of a sealing component; S2, preparing a plurality of diamond blocks (3), respectively placing the diamond blocks (3) into the micro grooves (2), and fixing the diamond blocks (3) and the substrate (1), so as to ensure that the upper end surfaces of the diamond blocks (3) protrude out of the end surfaces of the substrate (1); S3, arranging a metal coating layer (4) on the surfaces of the diamond (3) and the substrate (1) which are fixed by brazing, wherein the thickness of the metal coating layer (4) is higher than the protruding height of the diamond (3) block; and S4, grinding and polishing the end face of the base body (1) stacked with the metal coating (4) until the top ends of all the diamond (3) blocks are exposed, and enabling the whole end face to reach mirror-surface-level smoothness.
  2. 2. The method for preparing a sealing end face according to claim 1, wherein in the step S1, the diamond (3) and the substrate (1) are fixed in a manner including but not limited to active brazing, high-temperature glue bonding or in-situ ultrasonic crimping.
  3. 3. The method for preparing the sealing end face according to claim 2, wherein the diamond (3) and the substrate (1) are fixed in an active brazing mode, the active brazing is performed in vacuum, the brazing temperature is 800-900 ℃, and the brazing material is high-temperature brazing material containing active titanium.
  4. 4. The method for producing a sealing end face according to claim 1, wherein in step S1, the micro grooves (2) are produced by machining, laser machining or precision electric spark machining techniques.
  5. 5. The method for producing a sealing end face according to claim 1, wherein in step S2, the diamond (3) is a block of single crystal or polycrystalline diamond (3) subjected to chamfering treatment in advance.
  6. 6. The method for manufacturing the sealing end face according to claim 1, wherein in the step S3, the metal coating (4) is formed by adopting a spraying, overlaying or laser cladding welding process, and the metal coating (4) is a stainless steel powder, nickel-based hard alloy powder or cobalt-based hard alloy powder coating.
  7. 7. The method of manufacturing a sealing end face according to claim 1, wherein in the step S4, the mirror-surface finish is a surface roughness Ra of 0.1 μm or less.
  8. 8. A seal ring characterized in that a seal end face thereof is produced by the production method according to any one of claims 1 to 7.
  9. 9. The sealing ring according to claim 8, comprising an annular base body (1), wherein a plurality of blocks of diamonds (3) are arranged on the sealing end surface of the base body (1) in a circumferential array, a metal coating (4) is arranged on the end surface of the base body (1), and the metal coating (4) is flush with the outer end surfaces of the plurality of diamonds (3) to form an integral smooth plane.
  10. 10. The seal ring of claim 9, wherein the overall smooth planar surface has a roughness Ra of 0.1 μm or less.

Description

Sealing end face preparation method and sealing ring Technical Field The invention relates to the technical field of sealing, in particular to a sealing end face preparation method and a sealing ring. Background The mechanical seal is a key device widely applied to rotary mechanical shaft seals, and is commonly used in pumps, compressors, reaction kettles and other equipment in the process industries of chemical engineering, papermaking, pharmacy, food and the like. The basic sealing mechanism is that under the combined action of fluid pressure and the elastic force (or magnetic force) of the compensating mechanism, the end faces are matched with auxiliary sealing to ensure that the end faces are kept in contact and slide relatively, so as to realize the purpose of preventing leakage. Along with the development of industrial technology to high-temperature, high-pressure, high-speed and other high-parameter working conditions, friction pair materials adopted by the traditional mechanical seal, such as graphite, hard alloy, engineering ceramics and the like, face serious challenges in practical use. Under the high-load or extreme-temperature environment, the end face abrasion of the traditional materials is obviously increased, so that the sealing performance is reduced, the service life is shortened, and the design requirements of modern equipment on the sealing reliability and long-period operation are difficult to meet. In key friction pair components such as mechanical seal, dry gas seal, thrust bearing and the like, the wear resistance and surface finish of the end face directly influence the service life, sealing stability and energy consumption level of the equipment. For this reason, various surface strengthening techniques have been proposed in the industry to enhance friction pair performance, mainly including the following two classes: 1. Chemical Vapor Deposition (CVD) or Physical Vapor Deposition (PVD) ultra-hard film techniques typically used to deposit diamond or diamond-like films on sealed end surfaces. Diamond materials are considered ideal surface protection and reinforcement materials due to their excellent friction self-lubricity, high thermal conductivity, and corrosion resistance properties. Although the method can obtain higher surface finish and wear resistance, the following obvious defects still exist: 1) The edge area is easy to generate heat accumulation in the deposition process due to the influence of the geometric structure of the sealing ring, so that the thickness distribution of the film is uneven; 2) The bonding strength between the film and the matrix is obviously affected by the interface state, and the surface treatment requirement on the matrix is high; 3) For a workpiece with a complex structure, the processing cost is high, the process controllability is poor, and the excellent deposition of sealing rings with large size (such as 300mm outer diameter and above) level cannot be finished at present; 4) The diamond film has poor toughness, is easy to generate brittle fracture or peeling under the working condition of strong mechanical impact or thermal shock, and has limited application range. 2. The surface spraying hard coating technology is to prepare the hard coating of tungsten carbide, ceramic and the like by adopting a thermal spraying or cold spraying process. Although this approach improves surface hardness to some extent, there are also several inherent drawbacks: 1) The bonding strength between the coating and the matrix is generally insufficient, and when the coating is subjected to alternating stress, mechanical impact or thermal cycle load, partial peeling or overall failure is easy to occur; 2) The compactness and uniformity of the spray coating are often poor, and the overall wear resistance and corrosion resistance of the spray coating are affected; 3) The hardness of the spraying material is still far lower than that of diamond, the abrasion rate is higher under the extreme friction working condition, and the long-term reliability is limited. In view of the above, the ideal friction pair material needs to have high wear resistance, long life and good thermal conductivity to prevent wear failure. The silicon carbide and the hard alloy adopted by the friction pair hard ring material widely used at present have the advantages of high hardness (Mohs hardness is about 9), good wear resistance, corrosion resistance, mature process, relatively controllable cost and the like, and the wear resistance and the heat dissipation performance of the friction pair hard ring material still face challenges under the working conditions of extremely high speed, high pressure or strong corrosion. In contrast, diamond can realize near zero abrasion and high-efficiency heat dissipation by virtue of the characteristics of the hardest hardness (Mohs hardness 10), the ultrahigh heat conductivity and the surface non-wetting property, and is very suitable for being used as a frict