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CN-122014852-A - Packing sealing structure applied to high-pressure medium

CN122014852ACN 122014852 ACN122014852 ACN 122014852ACN-122014852-A

Abstract

The invention discloses a packing sealing structure applied to a high-pressure medium, which relates to the technical field of fluid mechanical sealing and comprises a pump body and a shaft body, wherein a pump cavity is arranged in the pump body, a packing box body is detachably arranged at the upper end of the pump body, a packing shaft sleeve is arranged in the packing box body, three groups of packing bodies are arranged in the sealing cavity, a lower water seal ring is arranged between two adjacent packing bodies below, a middle water seal ring is arranged between two adjacent packing bodies above, a packing gland is detachably arranged on the surface of the shaft body above the uppermost packing body, and a pressure relief hole is formed in the surface of the packing box body on one side of the middle water seal ring. The lower water seal ring and the middle water seal ring with larger height are arranged in a grading manner, so that the pressure of the medium is gradually reduced, accumulated and integrated from the high pressure of the pump cavity to the micro pressure, and the medium is timely discharged by matching with the pressure release hole, thereby solving the problems that the traditional single laminated packing is difficult to resist the impact of the high pressure medium and is easy to leak.

Inventors

  • CHANG JUDONG
  • LI CHENGHONG
  • XU JIAN
  • YU FENG

Assignees

  • 国电投(滨海)发电有限公司

Dates

Publication Date
20260512
Application Date
20260323

Claims (6)

  1. 1. The packing sealing structure for the high-pressure medium comprises a pump body (1) and a shaft body (2) and is characterized in that a pump cavity (3) is arranged in the pump body (1), a packing box body (4) is detachably arranged at the upper end of the pump body (1), a packing shaft sleeve (5) is arranged in the packing box body (4), the shaft body (2) is positioned in the packing shaft sleeve (5), a sealing cavity (6) is formed between the packing shaft sleeve (5) and the packing box body (4), three groups of packing bodies (21) are arranged in the sealing cavity (6), a lower water seal ring (7) is arranged between two groups of adjacent packing bodies (21) below, a water seal ring (8) is arranged between two groups of adjacent packing bodies (21) above, a packing gland (9) is detachably arranged on the surface of the shaft body (2) above the packing body (21), a pressure relief hole (10) is formed in the surface of the packing box body (4) on one side, a liquid collecting groove (11) is formed in the upper side, and a liquid collecting groove (11) is formed in the upper side of the liquid collecting groove (11).
  2. 2. The packing sealing structure applied to the high-pressure medium according to claim 1, wherein three through holes are formed in the upper end of the packing box body (4) in a circumferential array, connecting bolts (13) are arranged in the through holes, one ends of the connecting bolts (13) extend into the pump body (1) through screw holes, positioning columns (14) are arranged on two sides of the lower end of the packing box body (4), and one ends of the positioning columns (14) extend into the pump body (1).
  3. 3. The packing sealing structure applied to high-pressure medium according to claim 1, wherein the lower water seal ring (7) is smaller in height than the water seal ring (8).
  4. 4. The packing sealing structure applied to high-pressure media according to claim 1, wherein the number of the packing bodies (21) in each group is two, and the interfaces of the packing bodies (21) are distributed in a staggered mode.
  5. 5. The packing sealing structure applied to the high-pressure medium according to claim 1 is characterized in that inclined planes (15) are arranged at the bottom end of the sealing cavity (6) and the lower end of the packing gland (9).
  6. 6. The packing sealing structure applied to high-pressure media according to claim 1, wherein the packing gland (9) is of a split type design, the packing gland (9) is formed by combining two half-gland (16), the two half-gland (16) are connected and fixed through screws (17), mounting plates (18) are mounted on the surfaces of the two half-gland (16), connecting studs (19) are mounted at the upper ends of packing box bodies (4) below the mounting plates (18), the upper ends of the connecting studs (19) penetrate through the mounting plates (18), and nuts (20) are mounted on the surfaces of the connecting studs (19).

Description

Packing sealing structure applied to high-pressure medium Technical Field The invention relates to the technical field of fluid mechanical sealing, in particular to a packing sealing structure applied to a high-pressure medium. Background Packing seals (also known as packing seals) are used as a traditional and widely applied contact type seal, and have long been an important place in shaft end seals of fluid conveying equipment by virtue of their advantages of simple structure, low manufacturing cost, convenient disassembly and maintenance, etc. The core working principle is that the gland applies axial pressure to packing filler to enable the packing filler to expand radially, so that the packing filler is tightly attached to the surface of a rotating shaft and the inner wall of a sealing cavity to form a sealing surface to block a leakage channel of a medium. At present, when a conveying medium is in a high-pressure working condition (the pressure is more than or equal to 10 MPa), the traditional packing sealing structure gradually exposes a plurality of defects which are difficult to overcome, firstly, the sealing reliability is poor, leakage is easy to occur, the high-pressure medium can generate strong radial impact and permeation effect on the packing, the traditional packing is mostly made of single material or a simple laminated structure, the uniformity of radial expansion and the stability of compression quantity are difficult to ensure, a leakage channel is easy to form at the matching gap between the packing and a shaft as well as between the packing and a sealing cavity, so that the leakage of the high-pressure medium is caused, the medium is wasted, and safety accidents (such as inflammable, explosive and corrosive high-pressure medium leakage) can be caused; secondly, the packing wear speed is high, the service life is short, the contact pressure between the packing and the rotating shaft is obviously increased under the high-pressure working condition, meanwhile, the abrasion of the packing is increased due to the scouring of a high-pressure medium, in addition, the heat conduction performance of the traditional packing is poor, the heat generated by friction cannot be timely dissipated, the packing is easy to be carbonized and aged, the service life of the packing is further shortened, thirdly, the shaft wear risk is high, the interference fit of the packing and the shaft is increased under the high-pressure effect, the friction heat is accumulated, the surface of the shaft is easy to be damaged due to abrasion, strain and the like, if impurities are mixed in the packing, the abrasion of the shaft is accelerated, the transmission shaft is needed to be replaced when the abrasion of the shaft is serious, the equipment maintenance cost is further improved, fourthly, in order to improve the sealing effect under the high-pressure working condition, the traditional packing sealing is required to apply a larger axial compression force, the gland mechanism is required to have enough strength, and extremely high requirements are also provided for the control accuracy of the compression force in the installation process, namely the sealing is failed due to insufficient compression force, too large pressing force can aggravate abrasion of packing and shaft, increase rotation resistance and reduce equipment energy efficiency. Based on the above, a novel packing sealing structure which can adapt to high-pressure medium working conditions, has high sealing reliability, small abrasion and long service life and is convenient to install and maintain is developed, and the novel packing sealing structure becomes a technical problem to be solved in the current sealing technical field of water pumps and fluid conveying equipment. Disclosure of Invention The invention aims to provide a packing sealing structure applied to a high-pressure medium, so as to solve the problems in the background technology. The packing sealing structure comprises a pump body and a shaft body, wherein a pump cavity is formed in the pump body, a packing box body is detachably arranged at the upper end of the pump body, a packing shaft sleeve is arranged in the packing box body, the shaft body is positioned in the packing shaft sleeve, a sealing cavity is formed between the packing shaft sleeve and the packing box body, three groups of packing bodies are arranged in the sealing cavity, a lower water sealing ring is arranged between two adjacent packing bodies below the sealing cavity, a reclaimed water sealing ring is arranged between two adjacent packing bodies above the sealing ring, a packing gland is detachably arranged on the surface of the shaft body above the uppermost packing body, a pressure relief hole is formed in the surface of the packing box body on one side of the reclaimed water sealing ring, a liquid collecting tank is arranged at the upper end of the packing box body, a discharge hole is formed in one end of the liqui