CN-224229502-U - Reducing octagonal sealing gasket for butt joint of different-specification flanges

Abstract

The utility model relates to the technical field of petrochemical industry and mechanical sealing, and discloses a reducing octagonal sealing gasket for butt joint of irregular flanges, which comprises an annular sealing gasket body, wherein the sealing gasket body is formed by integrally connecting an upper gasket, a middle gasket and a lower gasket; the cross sections of the upper gasket and the lower gasket are hexagonal surfaces formed by five sides with one end being opened, the opening ends of the upper gasket and the lower gasket are opposite, the upper gasket and the lower gasket are arranged in a dislocation mode, the upper gasket and the lower gasket are connected through an obliquely arranged middle gasket, and the cross section of the middle gasket is a quadrangular surface formed by two oblique sides which are inclined from inside to outside. The sealing gasket can be directly arranged between flanges with different standard standards to be butted, reliable sealing connection is realized, and the design of the chamfer structure greatly improves the overall strength and the extrusion resistance of the sealing gasket.

Inventors

• ZHANG SAI
• GAO HAIJIANG
• HUANG HUAI
• YE JILONG
• ZHANG WENBO

Assignees

• 中盐榆林盐化有限公司

Dates

Publication Date

20260512

Application Date

20250702

Claims (3)

1. 1. The variable-diameter octagonal sealing gasket for butt joint of the irregular flanges is characterized by comprising an annular sealing gasket body, wherein the sealing gasket body is formed by integrally connecting an upper gasket, a middle gasket and a lower gasket, the sections of the upper gasket and the lower gasket are hexagonal surfaces formed by five sides with one open end, the upper gasket is opposite to the open end of the lower gasket, the upper gasket and the lower gasket are arranged in a dislocation mode, the upper gasket and the lower gasket are connected through the obliquely arranged middle gasket, the section of the middle gasket is a quadrilateral surface formed by two oblique sides which are inclined inwards and outwards, the top surface of the upper gasket is a pressed sealing contact surface of a small-diameter flange, and the bottom surface of the lower gasket is a pressed sealing contact surface of a large-diameter flange.
2. 2. The reducing octagon gasket for irregular flange butt joint according to claim 1, wherein the inclination angle of the intermediate gasket ranges from 40 ° to 50 °.
3. 3. A variable diameter octagonal gasket for use in butt-joint of dissimilar flanges according to claim 1 or 2, wherein the length of the inclined edge of the intermediate gasket is determined by the different values of the inner diameters of the two flanges to be joined.

Description

Reducing octagonal sealing gasket for butt joint of different-specification flanges Technical Field The utility model relates to the technical field of petrochemical engineering and mechanical sealing, in particular to a reducing octagonal sealing gasket for butt joint of different-specification flanges. Background In the industry of salt manufacturing and the like, it is often necessary to flange-dock equipment meeting petroleum specifications (e.g., GB/T22513) with equipment meeting chemical specifications (e.g., HG/T20592-20635). Because different standard standards have different requirements on the size of the flange (such as the width of a sealing surface, the pitch circle diameter of a bolt hole, the inner diameter and the like), the size deviation exists in direct butt joint, and effective sealing is difficult to form. The traditional solution is to use a specially-made reducing flange or reducing pipe for transitional connection. However, the variable-diameter flange or reducing pipe connecting scheme used in the prior art has the obvious defects that nonstandard parts are required to be independently customized, so that the material and processing cost is high, a large amount of nonstandard equipment is used to increase the difficulty of subsequent maintenance and spare part management, the length of the reducing pipe (generally more than 300 mm) is required to be additionally installed, the reducing pipe is limited in compact occasions, the overall rigidity of the system is reduced due to the fact that the lengthening pipeline is lengthened, and in addition, the installing process is generally required to be matched with additional flanges and fasteners, so that the complexity is increased. Disclosure of utility model In view of the above, the utility model provides a reducing octagonal sealing gasket for butt joint of different-specification flanges, which is a sealing structural member for connecting flanges of different-specification standards (such as chemical industry standards HG/T20592-20635 and petroleum and natural gas industry standards GB/T22513), and the specific technical scheme is as follows: The variable-diameter octagonal sealing gasket for the butt joint of the irregular flanges comprises an annular sealing gasket body, wherein the sealing gasket body is formed by integrally connecting an upper gasket, a middle gasket and a lower gasket, the sections of the upper gasket and the lower gasket are hexagonal surfaces formed by five sides with one open end, the upper gasket and the open end of the lower gasket are opposite, the upper gasket and the lower gasket are arranged in a staggered mode, the upper gasket and the lower gasket are connected through the middle gasket which is obliquely arranged, the section of the middle gasket is a tetragonal surface formed by two oblique sides which are obliquely arranged from inside to outside, the top surface of the upper gasket is a pressed sealing contact surface of a small-inner-diameter flange, and the bottom surface of the lower gasket is a pressed sealing contact surface of a large-inner-diameter flange. Preferably, the inclination angle of the middle gasket ranges from 40 degrees to 50 degrees. Preferably, the length of the inclined edge of the middle gasket is determined according to different inner diameter values of two flanges to be connected. The core application of the reducing octagonal sealing gasket for the butt joint of the different-specification flanges is that the reducing octagonal sealing gasket can be directly installed between flanges with different specification standards to be butt-jointed, and reliable sealing connection is realized. Compared with the prior art, the utility model has the advantages that the chamfer (namely the inclined middle gasket) is specially designed at the inner edge and the outer edge of the upper sealing surface and the lower sealing surface of the sealing gasket, and the chamfer structure can effectively disperse the stress generated when the sealing surface is pressed, particularly prevent the sharp edge from curling, cracking or plastic deformation under high pressure, and greatly improve the integral strength and the anti-extrusion capability of the sealing gasket. The utility model also improves the sealing contact, wherein the chamfer is helpful for guiding the flange sealing surface to contact with the gasket more smoothly, and generates tiny radial component force under the action of pretightening force, thereby having certain capability of compensating tiny parallelism deviation of the flange sealing surface. Drawings In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the following description will briefly explain the drawings used in the embodiments or the description of the prior art, and it is obvious that the drawings in the following description are only embodiments of the present utility model, and other