CN202302432U - Axial double-channel sealing structure for thin-wall flange flat groove for use under complex working condition - Google Patents

Abstract

The utility model provides a thin-walled flange flat groove axial double-channel sealing structure used in complex working conditions. Two ring grooves are provided on the end face of the lower flange in contact with the upper flange; The groove is a sealing groove for assembling rubber seals, and the inner ring groove is a flat groove for assembling polytetrafluoroethylene gaskets; rubber seals are placed in the sealing grooves for assembling rubber seals, and the compression amount of the rubber seals is 25 % to 40%; place a gasket that matches its shape in the flat groove of the PTFE gasket, the height of the gasket is 0.5 to 1.0mm greater than the depth of the flat groove, and the PTFE gasket The volume filling rate in the groove is 75-100%, and the end face thickness of the upper flange (1) or the lower flange (2) is 8mm-10mm. The rubber seal of the utility model produces flange deformation during use in a wide temperature range from low temperature to its extreme high temperature, and after the rubber seal is in contact with a strong corrosive medium, no redundant matter will be generated after being sealed and used at its extreme high temperature.

Description

Thin-wall flange flat groove axial double-channel sealing structure for complex working conditions

technical field

The utility model relates to a sealing structure under complex working conditions, in particular to a thin-walled flange flat groove axial double-channel sealing structure for complex working conditions.

Background technique

Rubber seals are widely used because of their simple sealing structure and high sealing reliability. Under the premise that the sealing technical requirements allow, rubber seals have always been the preferred sealing technical solution. Usually, according to the requirements of operating temperature, operating environment, and sealing pressure, the corresponding rubber seals are selected, and at the same time, the sealing surfaces of the upper and lower flanges are required to achieve a tight and seamless connection, so as to ensure reliable sealing requirements. However, in some specific cases, due to the constraints of assembly space conditions and weight reduction requirements, it is impossible to design a large and heavy sealing structure. It is required that the flange design of the sealing structure must be light in weight, thin in thickness and flexible in assembly. The structure will be deformed during the assembly process, and it will also be deformed during high temperature use. These deformations lead to increased seams on the flange sealing surface. Therefore, the traditional sealing structure design using rubber seals cannot meet the sealing requirements. It is necessary to carry out research on sealing structures that meet the requirements of light weight, flexible assembly, and deformation during use of rubber seals. On the other hand, after being in contact with strong corrosive media, ordinary rubber materials will produce redundant substances during high-temperature sealing and use, which will affect the normal use of precision systems such as valves.

Contents of the invention

The purpose of this utility model is to provide a thin-walled flange flat groove axial double-channel sealing structure for complex working conditions, and its rubber seals produce flanges during use in a wide temperature range from low temperature to extreme high temperature. Deformation, and after the rubber seal is in contact with strong corrosive media, it will not produce excess after sealing and using at its extreme high temperature. The flange deformation mentioned above comes from the deformation caused by normal temperature assembly and the deformation generated during the use of high temperature sealing. The deformation caused by normal temperature assembly makes the outer slit of the upper and lower flange surfaces reach a maximum of 0.2mm; the deformation generated during high temperature sealing makes the The maximum slit inside the flange reaches 2.25mm, and the maximum slit on the sealing surface where the rubber seal is placed reaches 1.25mm.

A thin-walled flange flat groove axial double-channel sealing structure for complex working conditions described in the utility model, in which the upper flange and the lower flange are butted, and are applied through several circumferentially arranged flanges. The parts of the pre-tightening force pass through the upper flange and the lower flange to realize the fast connection of the upper and lower flanges. Two ring grooves are set on the end face of the lower flange in contact with the upper flange; the outer ring groove is an assembly rubber The sealing groove of the seal, the inner ring groove is a flat groove for PTFE gaskets; a rubber seal is placed in the sealing groove of the rubber seal, and the compression of the rubber seal is 25% to 40%. ; Place a gasket that matches its shape in the flat groove where the polytetrafluoroethylene gasket is assembled. The filling rate is 75-100%; the thickness of the end face of the upper or lower flange is 8mm-10mm.

Another kind of thin-walled flange flat groove axial double-channel sealing structure for complex working conditions described in the utility model, wherein the lower flange is connected with the upper flange, and the outer diameter of the lower flange is smaller than that of the upper flange. The outer diameter of the upper and lower flanges is clamped by the loose ring, and at the same time, the fastening connection of the upper and lower flanges is realized by passing through the loose ring and the upper flange through several components that apply flange preload in the circumferential direction. Two ring grooves are set on the end face of the lower flange in contact with the upper flange, the outer ring groove is a sealing groove for assembling rubber seals, and the inner ring groove is a flat groove for assembling gaskets; A rubber seal is placed in the sealing groove, and the compression of the rubber seal is 25% to 40%; a gasket matching its shape is placed in the flat groove equipped with a polytetrafluoroethylene gasket, and the height of the gasket is greater than The depth of the flat groove is 0.5-1.0mm, and the volume filling rate of the polytetrafluoroethylene gasket in the flat groove is 75-100%; the thickness of the end face of the upper or lower flange is 8mm-10mm.

A thin-walled flange flat groove axial double-channel sealing structure for complex working conditions as described above, the rubber seal placed in the sealing groove equipped with rubber seals is made of fluorine rubber or Fluorine rubber or ethylene propylene rubber.

In the thin-walled flange flat groove axial double-channel sealing structure for complex working conditions as described above, the upper flange or lower flange is made of steel or aluminum.

In the thin-walled flange flat groove axial double-channel sealing structure for complex working conditions as described above, the components for applying flange pretightening force are bolts and nuts.

The utility model has the following effects:

The flange flat groove axial double-channel seal structure used in complex working conditions described in the utility model adopts the flange double-channel seal structure, the inner seal adopts polytetrafluoroethylene gaskets, and the outer seal adopts rubber seals , which solves the sealing problem of the sealing structure under the deformation condition in the strong corrosive medium environment. The deformation comes from the deformation generated by the normal temperature assembly and the deformation generated during the high temperature sealing process. The deformation generated by the normal temperature assembly makes the outer sides of the upper and lower flange surfaces The maximum slit is 0.2mm; the deformation generated during the high-temperature sealing process makes the maximum slit inside the flange reach 2.25mm, and the maximum slit on the sealing surface where the rubber seal is placed reaches 1.25mm.

The utility model carries out the above-mentioned sealing structure under the condition that the flange is deformed during the wide temperature range from -60°C to the extreme high temperature of the rubber seal, and the rubber seal is used at the extreme high temperature after contact with the strong corrosive medium. Sealing simulation assessment test, the test results show that the sealing structure does not leak, and there is no excess. Among them, the deformation caused by normal temperature assembly makes the outer slit of the upper and lower flange surfaces reach a maximum of 0.2mm; the deformation generated during the high-temperature sealing process makes the internal slit of the flange reach a maximum of 2.25mm, and the sealing surface where the rubber seal is placed has the largest slit up to 1.25mm.

Description of drawings

Fig. 1 is a schematic diagram of a flange flat groove axial double-channel seal structure used in complex working conditions described in Example 1;

Fig. 2 is a schematic diagram of a flange flat groove axial double-channel seal structure used in complex working conditions described in embodiment 3;

In the figure: 1-upper flange; 2-lower flange; 3-flat groove for assembly of PTFE gasket; 4-sealing groove for assembly of rubber seal; 5-parts for applying flange preload; 6 - Loop loops.

Detailed ways

A flange flat groove axial double-channel sealing structure used in complex working conditions according to the utility model will be further described below in conjunction with the accompanying drawings and specific embodiments.

Example 1

As shown in Figure 1, a flange flat groove axial double-channel sealing structure used under complex working conditions, in which the upper flange 1 and the lower flange 2 are butted, and several applied flanges arranged in the circumferential direction The parts 5 (bolts and nuts) of the pretightening force pass through the upper flange 1 and the lower flange 2 to realize the fast connection of the upper and lower flanges. The material of the flange is 5A06, the thickness of the end face of the upper flange is 10mm; the material of the lower flange is 1Cr18Ni9Ti, and the thickness of the end face of the lower flange is 8mm.

Two ring grooves are provided on the end face of the lower flange 2 which is in contact with the upper flange 1;

The outer ring groove is a sealing groove 4 for assembling rubber seals, the width of the sealing groove 4 is 4mm, and the groove depth is 2.25mm. The inner ring groove is a flat groove 3 for assembling a polytetrafluoroethylene gasket, the groove width of the flat groove 3 is 2mm, and the groove depth is 1mm.

Place a Φ3 fluoroether rubber O-shaped seal in the sealing groove 4 where the rubber seal is assembled, and the compression of the rubber seal is 25%.

Place a gasket matching its shape in the flat groove 3 where the polytetrafluoroethylene gasket is assembled. The gasket has a height of 2mm and a width of 1mm. And the volume filling rate of the polytetrafluoroethylene gasket in the flat groove is 100%.

The assembly process of the above-mentioned flange flat groove axial double seal structure used under complex working conditions is as follows: install the polytetrafluoroethylene gasket in the flat groove 3, and install the fluoroether rubber O-shaped seal in the sealing groove 4 middle. Use a torque wrench to tighten each bolt evenly and symmetrically, and increase the bolt tightening torque to 20N.m in 4 to 5 times, and then calibrate the torque twice along the circumferential direction. Using a plug gauge, the maximum gap between the upper and lower flanges is measured to be 0.2mm.

For the flat groove axial double-channel sealing structure assembled above, the sealing test at -60°C, the sealing test with the nitrogen tetroxide gas phase medium at 40°C for 150 hours (the contact pressure is 0.4MPa), and the sealing test with the four After exposure to the nitrous oxide gas phase medium, the sealing test at room temperature, low temperature -20°C and high temperature 360°C (test time 10 minutes, test pressure 0.9MPa) shows that no leakage occurred during the above test process. After the test tool was cooled to normal temperature, after disassembly and inspection, the internal slit of the test flange reached 2.05mm, the slit of the sealing surface where the rubber seal was placed reached 1.08mm, and there was no excess in the cavity of the test tool.

As a comparison, corresponding tests were carried out for the single-channel sealing structure (other conditions are the same as above) that do not include the flat groove of the PTFE gasket. And there is no leakage during the normal temperature and low temperature sealing test after medium contact, but leakage occurs during the high temperature 360 °C sealing test. After the test tooling was cooled to room temperature, it was disassembled and inspected. The internal slit of the test flange reached 2.02mm, the slit of the sealing surface where the rubber seal was placed reached 1.05mm, and the fluorine rubber seal was extruded to the inner edge of the test tool cavity.

Example 2

As shown in Figure 1, a flange flat groove axial double-channel sealing structure used under complex working conditions, in which the upper flange 1 and the lower flange 2 are butted, and several applied flanges arranged in the circumferential direction The parts 5 (bolts and nuts) of the pretightening force pass through the upper flange 1 and the lower flange 2 to realize the fast connection of the upper and lower flanges. The material of the upper flange is 2A14, and the end face thickness of the upper flange is 10mm; the material of the lower flange is 1Cr18Ni9Ti, and the end face thickness of the lower flange is 8mm.

Two ring grooves are provided on the end face of the lower flange 2 which is in contact with the upper flange 1;

The outer ring groove is a sealing groove 4 for assembling rubber seals, the width of the sealing groove 4 is 4mm, and the groove depth is 1.8mm. The inner ring groove is a flat groove 3 for assembling a polytetrafluoroethylene gasket, the groove width of the flat groove 3 is 2mm, and the groove depth is 1mm.

Place Φ3 ethylene-propylene rubber O-shaped seals in the sealing groove 4 where the rubber seals are assembled, and the compression of the rubber seals is 40%.

Place a gasket matching its shape in the flat groove 3 where the polytetrafluoroethylene gasket is assembled. The gasket has a height of 1.5mm and a width of 1mm. The volume filling rate of the PTFE gasket in the flat groove is 75%.

The assembly process of the above-mentioned flange flat groove axial double-channel seal structure used under complex working conditions is as follows: install the polytetrafluoroethylene gasket in the flat groove 3, and install the ethylene propylene rubber O-shaped seal in the sealing groove 4 middle. Use a torque wrench to tighten each bolt evenly and symmetrically, and increase the bolt tightening torque to 20N.m in 4 to 5 times, and then calibrate the torque twice along the circumferential direction. Using a plug gauge, the maximum gap between the upper and lower flanges is measured to be 0.2mm.

For the flat groove axial double-channel sealing structure assembled above, the sealing test at -60°C, the sealing test with the unsymmetrical dimethylhydrazine gas phase medium at 40°C for 150 hours (contact pressure is 0.5MPa), and the sealing test with the biased After exposure to the dimethylhydrazine gas phase medium, the sealing test at room temperature, low temperature -20°C and high temperature 345°C (test time 10 minutes, test pressure 0.95MPa) showed that no leakage occurred during the above test process. After the test tool was cooled to normal temperature, after disassembly and inspection, the internal slit of the test flange reached 1.75mm, the slit of the sealing surface where the rubber seal was placed reached 0.85mm, and there was no excess in the cavity of the test tool.

As a comparison, for the single-channel sealing structure (other conditions are the same as above) that do not include the flat groove of the PTFE gasket, the corresponding sealing tests were carried out. After the process and medium contact, there is no leakage during the normal temperature and low temperature sealing test, but there is leakage during the high temperature 345°C sealing test. After the test tool was cooled to room temperature, after disassembly and inspection, the internal slit of the test flange reached 1.72mm, and the slit of the sealing surface where the rubber seal was placed reached 0.84mm. There was a black paint-like substance in the cavity of the test tool.

Example 3

As shown in Figure 2, a flange flat groove axial double-channel sealing structure used under complex working conditions, in which the upper flange 1 and the lower flange 2 are butted, and the outer diameter of the lower flange 2 is smaller than the upper flange 1, and then clamp the lower flange 2 through the loop ring 6, and at the same time pass through the loop ring 6 and the upper flange 1 through several components 5 (bolts and nuts) arranged in the circumferential direction to apply the flange pretightening force Realize the tight connection of the upper and lower flanges with the lower flange 2. The material of the upper flange is 5A06, and the end face thickness of the upper flange is 10mm; the material of the lower flange is 1Cr18Ni9Ti, and the end face thickness of the lower flange is 8mm.

Two ring grooves are provided on the end face of the lower flange 2 which is in contact with the upper flange 1;

The outer ring groove is a sealing groove 4 for assembling rubber seals, the width of the sealing groove 4 is 4mm, and the groove depth is 2.25mm. The inner ring groove is a flat groove 3 for assembling a polytetrafluoroethylene gasket, the groove width of the flat groove 3 is 2mm, and the groove depth is 1mm.

Place a Φ3 fluoroether rubber O-shaped seal in the sealing groove 4 where the rubber seal is assembled, and the compression of the rubber seal is 25%.

Place a gasket matching its shape in the flat groove 3 where the polytetrafluoroethylene gasket is assembled. The gasket has a height of 2mm and a width of 1mm. And the volume filling rate of the polytetrafluoroethylene gasket in the flat groove is 100%.

The assembly process of the above-mentioned flange flat groove axial double seal structure used under complex working conditions is as follows: install the polytetrafluoroethylene gasket in the flat groove 3, and install the fluoroether rubber O-shaped seal in the sealing groove 4 , place a loose ring on the lower flange, and then use a torque wrench to tighten the bolts evenly and symmetrically. Add the bolt tightening torque to 20N.m in 4 to 5 times, and then calibrate the torque twice along the circumferential direction. Using a plug gauge, the maximum clearance outside the upper and lower flanges is measured to be 0.2mm.

For the flat groove axial double-channel sealing structure assembled above, the sealing test at -60°C, the sealing test with the nitrogen tetroxide gas phase medium at 40°C for 150 hours (the contact pressure is 0.4MPa), and the sealing test with the four After exposure to the nitrous oxide gas phase medium, the sealing test at room temperature, low temperature -20°C and high temperature 360°C (test time 10 minutes, test pressure 0.9MPa) shows that no leakage occurred during the above test process. After the test tooling was cooled to room temperature, it was disassembled and inspected. The internal slit of the test flange reached 2.25mm, and the slit of the sealing surface where the rubber seal was placed reached 1.28mm. There was no excess in the cavity of the test tooling.

As a comparison, corresponding tests were carried out for the single-channel sealing structure (other conditions are the same as above) that do not include the flat groove of the PTFE gasket. And there is no leakage during the normal temperature and low temperature sealing test after medium contact, but leakage occurs during the high temperature 360 °C sealing test. After the test tooling was cooled to room temperature, it was disassembled and inspected. The internal slit of the test flange reached 2.25mm, the slit of the sealing surface where the rubber seal was placed reached 1.25mm, and the fluorine rubber seal was extruded to the inner edge of the test tool cavity.

Example 4

As shown in Figure 2, a flange flat groove axial double-channel sealing structure used under complex working conditions, in which the upper flange 1 and the lower flange 2 are butted, and the outer diameter of the lower flange 2 is smaller than the upper flange 1, and then clamp the lower flange 2 through the loop ring 6, and at the same time pass through the loop ring 6 and the upper flange 1 through several components 5 (bolts and nuts) arranged in the circumferential direction to apply the flange pretightening force Realize the tight connection of the upper and lower flanges with the lower flange 2. The material of the upper flange is 2A14, and the end face thickness of the upper flange is 10mm; the material of the lower flange is 1Cr18Ni9Ti, and the end face thickness of the lower flange is 8mm.

Two ring grooves are provided on the end face of the lower flange 2 which is in contact with the upper flange 1;

The outer ring groove is a sealing groove 4 for assembling rubber seals, the width of the sealing groove 4 is 4mm, and the groove depth is 1.8mm. The inner ring groove is a flat groove 3 for assembling a polytetrafluoroethylene gasket, the groove width of the flat groove 3 is 2mm, and the groove depth is 1mm.

A Φ3 ethylene-propylene rubber O-shaped seal is placed in the sealing groove 4 where the rubber seal is assembled, and the compression of the rubber seal is 40%.

Place a gasket matching its shape in the flat groove 3 where the polytetrafluoroethylene gasket is assembled. The gasket has a height of 1.5mm and a width of 1mm. And the volume filling rate of the polytetrafluoroethylene gasket in the flat groove is 75%.

The assembly process of the above-mentioned flange flat groove axial double-channel seal structure used under complex working conditions is as follows: install the polytetrafluoroethylene gasket in the flat groove 3, and install the ethylene propylene rubber O-shaped seal in the sealing groove 4 , place a loose ring on the lower flange, and then use a torque wrench to tighten the bolts evenly and symmetrically. Add the bolt tightening torque to 20N.m in 4 to 5 times, and then calibrate the torque twice along the circumferential direction. Using a plug gauge, the maximum clearance outside the upper and lower flanges is measured to be 0.2mm.

For the flat groove axial double-channel sealing structure assembled above, the sealing test at -60°C, the sealing test with the unsymmetrical dimethylhydrazine gas phase medium at 40°C for 150 hours (contact pressure is 0.5MPa), and the sealing test with the biased After exposure to the dimethylhydrazine gas phase medium, the sealing test at room temperature, low temperature -20°C and high temperature 345°C (test time 10 minutes, test pressure 0.95MPa) showed that no leakage occurred during the above test process. After the test tool was cooled to room temperature, it was disassembled and inspected. The internal slit of the test flange reached 2.1mm, and the slit of the sealing surface where the rubber seal was placed reached 1.08m. There was no excess in the cavity of the test tool.

As a comparison, for the single-channel sealing structure (other conditions are the same as above) that do not include the flat groove of the PTFE gasket, the corresponding sealing tests were carried out. After the process and medium contact, there is no leakage during the normal temperature and low temperature sealing test, but there is leakage during the high temperature 345°C sealing test. After the test tooling was cooled to room temperature, it was disassembled and inspected. The internal slit of the test flange reached 2.11mm, and the slit of the sealing surface where the rubber seal was placed reached 1.08mm. There was a black paint-like substance in the cavity of the test tooling.

Claims (5)

1. A thin-walled flange flat groove axial double-channel sealing structure for complex working conditions, in which the upper flange (1) and the lower flange (2) are butted, and are applied by several circumferentially arranged The part (5) of the flange preload passes through the upper flange (1) and the lower flange (2) to realize the fastening connection of the upper and lower flanges, which is characterized in that: the lower flange is in contact with the upper flange (1) There are two ring grooves on the end face of the flange (2); the outer ring groove is a sealing groove (4) for assembling rubber seals, and the inner ring groove is a flat groove (3) for assembling a polytetrafluoroethylene gasket; Place a rubber seal in the sealing groove (4) where the rubber seal is assembled, and the compression of the rubber seal is 25% to 40%; place it in the flat groove (3) that is equipped with a polytetrafluoroethylene gasket to match its shape gasket, the height of the gasket is 0.5-1.0mm greater than the depth of the flat groove, and the volume filling rate of the polytetrafluoroethylene gasket in the flat groove is 75-100%; the upper flange (1) or The end face thickness of the lower flange (2) is 8mm-10mm. 2. A thin-walled flange flat groove axial double-channel sealing structure for complex working conditions, wherein the lower flange (2) is docked with the upper flange (1), and the outer diameter of the lower flange (2) The outer diameter of the upper flange (1) is smaller than that of the upper flange (1), and then the lower flange (2) is clamped by the looper ring (6), and at the same time, the looper is passed through several components (5) arranged in the circumferential direction to apply flange pretightening force The ring (6) and the upper flange (1) realize the fast connection of the upper and lower flanges, which is characterized in that two ring grooves are provided on the end surface of the lower flange (2) in contact with the upper flange (1), and the outer One ring groove is the sealing groove (4) for assembling the rubber seal, and the inner ring groove is the flat groove (3) for assembling the gasket; the rubber seal is placed in the sealing groove (4) for assembling the rubber seal, and the rubber The compression of the seal is 25% to 40%; place a gasket matching its shape in the flat groove (3) where the polytetrafluoroethylene gasket is assembled, and the height of the gasket is 0.5 to 1.0 greater than the depth of the flat groove mm, and the volume filling rate of the polytetrafluoroethylene gasket in the flat groove is 75-100%; the end face thickness of the upper flange (1) or lower flange (2) is 8mm-10mm. 3. A thin-walled flange flat groove axial double-channel sealing structure for complex working conditions according to claim 1 or 2, characterized in that: the sealing groove placed in the assembly rubber seal (4) The material of the rubber seal inside is selected from fluorine rubber, fluorine ether rubber or ethylene propylene rubber. 4. A thin-walled flange flat groove axial double-channel sealing structure for complex working conditions according to claim 1 or 2, characterized in that: the upper flange (1) or the lower flange Blue (2) selects steel or aluminum material for use. 5. A thin-walled flange flat groove axial double-channel sealing structure for complex working conditions according to claim 1 or 2, characterized in that: said parts applying flange preload ( 5) For bolts and nuts.

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