A visual seal compression ratio measurement device and method

Abstract

This invention belongs to the field of mechanical assembly, specifically relating to a visual sealing component compression ratio measurement device and method. The device includes fastening bolts, an upper assembly flange, a sealing component, a lower assembly flange, fastening nuts, and a standard color matching tape. The upper and lower assembly flanges are connected and fixed by fastening bolts and nuts. The sealing component is installed on the platform of the lower assembly flange. The fastening bolts and nuts are adjusted to compress the sealing component. After tightening, the color of the sealing component is observed and compared with the standard color matching tape to confirm the compression ratio of the sealing component. This invention simplifies the flange tightening process, avoids the use of measuring instruments such as vernier calipers, depth gauges, and feeler gauges, and has lower personnel qualification requirements, effectively improving the efficiency and quality of flange tightening work.

Description

Technical Field

[0001] This invention belongs to the field of mechanical assembly, and specifically relates to a visual sealing component compression ratio measurement device and method. Background Technology

[0002] A domestic nuclear power plant has over 60,000 valves installed across its four operating units. Most valves and pipelines are connected via flanges, and some pipelines are also connected by flanges. The power plant system's media primarily consist of gaseous steam and liquid feedwater, with steam pressures reaching up to 10 MPa. Steam leaks could directly cause burns to workers and damage to equipment. Due to the large number of flanges installed in the operating system and the varying skill levels of maintenance personnel, flange leaks are frequently observed during routine maintenance. Depending on the specific leak location, the system requires isolation and repair, directly impacting normal operation. For some critical and sensitive systems, shutdown for maintenance is necessary, directly shortening the safe and stable operating time of the units, reducing power generation, and affecting the overall efficiency of the power plant.

[0003] During normal operation of the unit, all system equipment flanges must not experience prolonged leaks. Some critical systems require zero leakage. This necessitates that the gaskets installed at the system flanges meet procedural requirements. As a key process in flange tightening—the control of the compression ratio of the sealing element 3—is extremely important. The conventional flange tightening and installation process places extremely high demands on the operators. From the fabrication of the gaskets, the measurement of the mating flange data, flange mating, to flange tightening, the entire process must be strictly controlled without any errors. Each operator must be able to correctly use measuring instruments such as vernier calipers, depth gauges, and feeler gauges. The flange tightening method also has special requirements, making quality control in this process quite stringent.

[0004] Based on past experience with flange installation, it is necessary to select appropriate sealing materials according to factors such as the nominal diameter of the system piping, nominal pressure, medium operating temperature, medium properties, application, flange size, pressure rating, sealing surface type, surface geometry, and the sealing performance of the sealing material itself. Following the relevant technical procedures for power plants, gaskets, mating flanges, and gasket tightening are then performed. A key step is the gasket tightening process. Using conventional methods, depending on the flange type, multiple dimensions need to be measured and relevant data calculated. For flat / raised face flanges, the actual thickness of the gasket needs to be measured before installation; mating flanges do not require gaskets. The gap between the flanges and the mating flanges after compression; for tongue and groove flanges, before installing the gasket, it is necessary to measure the actual thickness of the gasket, the height of the boss, the depth of the recess, the initial gap of the mating flanges without gaskets, and the final gap of the mating flanges after compression; the whole process requires the use of measuring instruments such as vernier calipers, depth gauges, and feeler gauges multiple times, which introduces certain measurement errors. In addition, changes in the on-site working environment can cause additional measurement errors; and it requires a high level of education for on-site personnel, who need to be able to correctly use relevant measuring instruments and calculate the compression rate of the gaskets correctly, which places high demands on manpower, material resources, and the environment.

[0005] Therefore, there is a need to provide a device and method for visually measuring the compression ratio of seals to solve the problems existing in the prior art. Summary of the Invention

[0006] The purpose of this invention is to provide a visual sealing compression ratio measurement device and method, which simplifies the flange tightening process, avoids the use of measuring instruments such as vernier calipers, depth gauges, and feeler gauges, and has lower personnel qualification requirements, thereby effectively improving the work efficiency and quality of flange tightening.

[0007] Technical solution to achieve the purpose of this invention:

[0008] A visual seal compression ratio measuring device includes fastening bolts, an upper mounting flange, a seal, a lower mounting flange, fastening nuts, and a standard color matching strip.

[0009] The upper and lower assembly flanges are connected and fixed by fastening bolts and nuts. The seal is installed on the platform of the lower assembly flange. The fastening bolts and nuts are adjusted to press the seal tight. After tightening, the color of the seal is observed and compared with the standard color band to confirm the compression rate of the seal.

[0010] The types of upper and lower assembly flanges include flat flanges, raised face flanges, male and female flanges, and tongue and groove flanges.

[0011] The sealing materials for the standard color matching tape include flexible graphite, polytetrafluoroethylene, rubber, carbon fiber, copper, aluminum, and stainless steel.

[0012] To prevent abnormal damage to local areas during the tightening process of the seal, the position and force of the tightening bolts and nuts must be adjusted in real time according to the color change of the seal. After tightening, confirm that the final color of the seal is consistent with the color within the required compression range on the standard color reference tape, and the seal tightening work is completed.

[0013] A measurement method for a visual seal compression ratio measuring device, the method comprising the following steps:

[0014] Step 1: Remove the connecting flanges and old gaskets from the system piping, and clean the gasket installation area;

[0015] Step 2: Seal the openings of the upper and lower assembly flanges, measure the specific dimensions of the sealing components at the assembly positions of the upper and lower assembly flanges, determine the dimensions of the sealing components, and make sealing gaskets.

[0016] Step 3: Trim the sealing gasket, adjust the gap and concentricity between the upper and lower assembly flanges, and check and clean the installation position of the sealing gasket.

[0017] Step 4: Install the sealing gasket, tighten the bolts and nuts;

[0018] Step 5: Initially tighten the upper and lower assembly flanges, and record the initial color and chromaticity of the seals;

[0019] Step 6: Tighten the sealing gasket and determine the compression ratio.

[0020] Step 1 includes the following steps:

[0021] Step 1.1 After isolating the system pipeline, place water receiving devices at the upper and lower assembly flanges, and loosen the fastening bolts and nuts;

[0022] Step 1.2 Disconnect the upper assembly flange from the lower assembly flange, remove the seal, seal the pipe opening of the lower assembly flange, clean the foreign objects on the seal and store it.

[0023] Step 1.3 Clean and repair the sealing areas of the upper and lower assembly flanges.

[0024] Step 2 includes the following steps:

[0025] Step 2.1 Clean and repair the sealing installation position between the upper and lower assembly flanges, remove the seal on the lower assembly flange, and use a special anti-foreign object blocking plate to seal the upper and lower assembly flanges.

[0026] Step 2.2 Select the material of the seal according to the operating conditions of the system, and make the sealing gasket according to the assembly position dimensions of the seal between the upper and lower assembly flanges.

[0027] The dimensional requirements for the sealing elements vary depending on the type of flange, including:

[0028] (1) Flat / Raised Face Flange

[0029] Shim outer diameter = bolt hole pitch circle diameter - bolt diameter - 1mm;

[0030] Gasket inner diameter = assembly flange inner diameter + 2mm;

[0031] (2) Raised Face Flange

[0032] Gasket outer diameter = concave platform diameter - 2mm;

[0033] Gasket inner diameter = assembly flange inner diameter + 2mm;

[0034] (3) Tongue and groove flange

[0035] Gasket outer diameter = groove major diameter - 2mm;

[0036] The inner diameter of the gasket = the minor diameter of the groove + 2mm.

[0037] Step 3 includes the following steps:

[0038] Step 3.1 Repair the inner and outer rounded corners of the completed seal;

[0039] Step 3.2 Measure the gap between the upper and lower assembly flanges when the seal is not installed, and ensure that the gap is no greater than the thickness of the seal + 1mm. Adjust the gap as needed by adjusting the fastening bolts and nuts.

[0040] Step 3.3 Measure the concentricity of the upper and lower assembly flanges;

[0041] Step 3.4 Remove the foreign object blocking plates at the upper and lower assembly flanges and clean the sealing surfaces.

[0042] Step 4 includes the following steps:

[0043] Step 4.1 Insert some of the fastening bolts into the upper and lower assembly flanges, and place the newly made seals into the upper and lower assembly flanges;

[0044] Step 4.2 Install all remaining fastening bolts into the upper and lower assembly flanges, and screw the fastening nuts from the lower assembly flange into the fastening bolts.

[0045] Step 5 includes the following steps:

[0046] Step 5.1 Secure the upper assembly flange and fastening bolts, rotate the fastening nut below the lower assembly flange, and check the contact between the seal and the lower contact surface of the upper assembly flange and the upper contact surface of the lower assembly flange.

[0047] Step 5.2 Record the initial color-chromaticity of the seal.

[0048] Step 6 includes the following steps:

[0049] Step 6.1 Tighten the fastening nuts symmetrically according to the cross method, fix the fastening bolts and tighten the fastening nuts, record the color of the seal after tightening, compare the recorded color with the standard color reference tape, and record the compression rate of the seal after this tightening.

[0050] Step 6.2 If the compression ratio does not meet the compression ratio requirement of the sealing gasket material, repeat step 6.2 and record the color of the seal until the compression ratio of the sealing gasket meets the standard requirements.

[0051] The beneficial technical effects of this invention are as follows:

[0052] 1) This invention can simultaneously measure the compression ratio of seals made of different materials. The compression ratio of the seal after tightening is determined by comparing the color of the seal with the standard color strip of the device, without the need to manufacture seals of each material separately.

[0053] 2) This invention measures the compression ratio of a seal without requiring torque wrenches, vernier calipers, depth gauges, or feeler gauges during seal installation, saving installation time and effectively improving equipment installation efficiency; it avoids measurement errors caused by using measuring instruments, improving the accuracy of the seal compression ratio; it has a wide range of applications, with no requirements on the installation position of the seal or the measurement space, and can be measured even in confined spaces without considering the requirements of traditional measuring instruments; it can save half the personnel input and reduce installation costs.

[0054] 3) The device in this invention is simple to use. Compared with measuring instruments such as torque wrenches, vernier calipers, depth gauges and feeler gauges, it does not require special skills from the operator. The compression rate can be determined by comparing the color of the seal with the color of the standard tape on the device. The device in this invention can be fixed on a file bag or other toolbox, and foreign object control can be achieved without taking foreign object prevention measures.

[0055] 4) The device in this invention has great potential for widespread application. It is the first of its kind in the domestic and international markets and is applicable to the measurement and inspection of the compression ratio of different seals in different industries, filling a technological gap in this field in China. Attached Figure Description

[0056] Figure 1A schematic diagram of a visual seal compression ratio measuring device provided by the present invention;

[0057] In the diagram: 1-Fastening bolt; 2-Upper assembly flange; 3-Seal; 4-Lower assembly flange; 5-Fastening nut; 6-Standard color matching tape. Detailed Implementation

[0058] To enable those skilled in the art to better understand the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments described in the present invention without creative effort are within the scope of protection of the present invention.

[0059] like Figure 1 As shown, the present invention provides a visual seal compression ratio measuring device, which includes a fastening bolt 1, an upper mounting flange 2, a lower mounting flange 4, a fastening nut 5, and a standard color matching strip 6.

[0060] The upper assembly flange 2 and the lower assembly flange 4 are connected and fixed by fastening bolts 1 and fastening nuts 5. The types of upper assembly flange 2 and lower assembly flange 4 include flat flanges, raised face flanges, male and female flanges, and tongue and groove flanges. Figure 1 The center is a raised face flange;

[0061] The standard color matching tape 6 can be made into a compression ratio comparison table for various sealing materials according to the requirements of field use. Common sealing materials include flexible graphite, polytetrafluoroethylene, rubber, carbon fiber, copper, aluminum and stainless steel.

[0062] The seal 3 is installed on the platform of the lower assembly flange 4. The fastening bolts 1 and fastening nuts 5 are adjusted to press the seal 3. After tightening, the color of the seal 3 is observed and compared with the standard color comparison band 6 to confirm the compression rate of the seal 3. This is intuitive and accurate, and no measuring instruments are required during the process.

[0063] To prevent abnormal damage to local areas during the tightening of seal 3, the position and force of the tightening bolts 1 and tightening nuts 5 must be adjusted in real time according to the color change of seal 3. After tightening, confirm that the final color of seal 3 is consistent with the color within the required compression range on the standard color comparison tape 6, and the tightening of seal 3 is complete.

[0064] The present invention also provides a measurement method for a visual seal compression ratio measuring device, the method comprising the following:

[0065] Step 1: Remove the connecting flanges and old gaskets from the system piping, and clean the gasket installation area.

[0066] Step 1.1 After the system pipeline is isolated, place water receiving devices at the upper assembly flange 2 and the lower assembly flange 4. Use an open wrench to loosen the fastening bolts 1 and fastening nuts 5, and place the removed fastening bolts 1 and fastening nuts 5 in the fixed storage box.

[0067] When the water receiving device contains toxic or hazardous substances, operators must wear special protective equipment.

[0068] Step 1.2 Disconnect the upper assembly flange 2 from the lower assembly flange 4. Use a flathead screwdriver or a special seal removal device to remove the seal 3. When removing the gasket, take precautions against foreign objects. Use wiping paper or other special sealing tools to seal the pipe opening at the lower assembly flange 4 to prevent debris from the old seal 3 from falling into the pipe below. Clean the burrs on the seal 3 and store it in the designated location.

[0069] Step 1.3 Use a scouring pad and wiping paper to clean the sealing areas of the upper assembly flange 2 and the lower assembly flange 4, especially the installation position of the seal 3. If scratches or pits are found at the installation position of the seal 3, use repair tools to grind and weld the area. If there are large defects on the flange, remove the flange from the system pipeline and repair it on a lathe to ensure that the flatness of the repaired sealing surface meets the reinstallation requirements to prevent external leakage after the equipment is reinstalled.

[0070] Step 2: Seal the upper and lower flange openings, measure the specific dimensions of the assembly positions of the upper assembly flange 2 and the lower assembly flange 4 sealing element 3, determine the detailed dimensions of the sealing element 3 to be manufactured, and manufacture the sealing gasket.

[0071] Step 2.1 Use special tools to clean and repair the installation position of the seal 3 between the upper assembly flange 2 and the lower assembly flange 4. Remove the sealing device from the lower assembly flange 4 port. Do not let the debris fall into the pipe below. Use a special anti-foreign object plug to seal the upper assembly flange 2 and the lower assembly flange 4.

[0072] Step 2.2 Select the material of the sealing element 3 according to the operating conditions of the system (mainly including system pressure, temperature, medium properties and application conditions, etc.), and use a hole opener and a gasket cutter to make a sealing gasket according to the assembly position dimensions of the sealing element 3 between the upper assembly flange 2 and the lower assembly flange 4.

[0073] The dimensional requirements for sealing element 3 vary depending on the type of flange, as detailed below:

[0074] (1) Flat / Raised Face Flange

[0075] Shim outer diameter = bolt hole pitch circle diameter - bolt diameter - 1mm;

[0076] Gasket inner diameter = assembly flange inner diameter + 2mm.

[0077] (2) Raised Face Flange

[0078] Gasket outer diameter = concave platform diameter - 2mm;

[0079] Gasket inner diameter = assembly flange inner diameter + 2mm;

[0080] (3) Tongue and groove flange

[0081] Gasket outer diameter = groove major diameter - 2mm;

[0082] The inner diameter of the gasket = the minor diameter of the groove + 2mm.

[0083] Step 3: Trim the gasket, adjust the gap and concentricity between the upper and lower flanges, and check and clean the gasket installation position.

[0084] Step 3.1 Use a mixed file to repair the inner and outer rounded corners of the completed seal 3. For sealing gaskets that are easy to loosen, use tools with a certain degree of smoothness to repair them, so as to prevent damage to the seal 3 during reassembly, which could cause the loose part of the seal 3 to fall into the system pipeline and cause damage to the rotating equipment.

[0085] Step 3.2 Measure the gap between the upper assembly flange 2 and the lower assembly flange 4 when the seal 3 is not installed, and ensure that the gap is not greater than the thickness of the seal 3 + 1mm under the condition that no external force is used. Adjust it in time by adjusting the fastening bolts 1 and nuts.

[0086] Step 3.3 Measure the concentricity of the upper assembly flange 2 and the lower assembly flange 4. Since the pipes where the upper assembly flange 2 and the lower assembly flange 4 are located are in different installation positions and under different stress conditions, there may be some deviation. In order to ensure the sealing of the equipment after reassembly, all 8 fastening bolts 1 need to be inserted into the upper and lower assembly bolts, and they can pass through freely.

[0087] Step 3.4 Remove the foreign object blocking plates at the upper assembly flange 2 and the lower assembly flange 4, clean the sealing surface with cleaning agent, wipe it dry with wiping paper, and ensure that the cleanliness of the upper assembly flange 2 and the lower assembly flange 4 within the visible range meets the reinstallation requirements and there are no visible foreign objects. In order to prevent the connection between the fastening bolt 1 and the fastening nut 5 from seizing, the sealing element 3 needs to be coated with bolt anti-seize agent on the thread before installation.

[0088] Step 4: Install sealing gaskets and fasteners

[0089] Step 4.1 Insert the four consecutively installed fasteners 1 into the upper assembly flange 2 and the lower assembly flange 4. Place the newly made seal 3 into the upper assembly flange 2 and the lower assembly flange 4. During installation, be careful to prevent the gasket from being scratched by the threads of the fastening bolts 1. Check the installation status of the seal 3 to ensure that the seal 3 is completely placed into the groove of the lower assembly flange 4.

[0090] Step 4.2 Install the remaining 4 fastening bolts 1 into the upper assembly flange 2 and the lower assembly flange 4, and screw the 8 fastening nuts 5 into the fastening bolts 1 from the lower assembly flange 4.

[0091] Step 5: Initially tighten the upper and lower flanges, and record the initial color of seal 3 - chromaticity 1.

[0092] Step 5.1 Use an open-end wrench or other fastening tools to tighten the fastening bolts 1 of the upper mounting flange 2, and use the tools to rotate the fastening nut 5 under the lower mounting flange 4 to check that the seal 3 just makes contact with the lower contact surface of the upper mounting flange 2 and the upper contact surface of the lower mounting flange 4.

[0093] Step 5.2 Record the initial color of seal 3 - chromaticity 1. Under normal circumstances, the initial color of seal 3 should be consistent with the base material of the sealing material.

[0094] Step 6: Tighten the sealing gasket and determine the compression ratio.

[0095] Step 6.1 One operator symmetrically tightens 8 fastening nuts 5 using the cross method. The same person fixes the fastening bolt 1 and tightens the fastening nuts 5 to ensure that the tightening torque values ​​are approximately the same. Record the color 2 of the seal 3 after tightening. Compare the recorded color 2 with the standard color reference tape 6 and record the compression rate of the seal 3 after this tightening.

[0096] Step 6.2 Compare the color of the tightened gasket with the standard color reference band 6. If the compression ratio corresponding to color 2 does not meet the compression ratio requirement of the sealing gasket material, use the same method to tighten all the fastening nuts 5 for a second round, and increase the tightening torque. After all the fastening nuts 5 are tightened, record the gasket color 3, compare color 3 with the standard color reference band 6, and confirm whether the compression ratio of the seal 3 meets the standard requirement. If the compression ratio still does not meet the requirement, repeat the above steps until the compression ratio of the sealed gasket meets the standard requirement. After the compression ratio of the seal 3 meets the requirement, use the same force to check the nut clockwise for 1.5 turns.

[0097] The present invention has been described in detail above with reference to the accompanying drawings and embodiments. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. All contents not described in detail in the present invention can be derived from existing technologies.

Claims

1. A visualizing seal compression rate measuring device characterized by: The device comprises a fastening bolt (1), an upper assembly flange (2), a sealing element (3), a lower assembly flange (4), a fastening nut (5) and a standard color comparison strip (6); The upper assembly flange (2) and the lower assembly flange (4) are connected and fixed by the fastening bolt (1) and the fastening nut (5), the sealing element (3) is installed on the platform of the lower assembly flange (4), the fastening bolt (1) and the fastening nut (5) are adjusted to compress the sealing element (3), and the color of the sealing element (3) is observed after fastening, compared with the standard color comparison strip (6), and the compression rate of the sealing element (3) is confirmed; The standard color comparison strip (6) is a compression rate comparison table of sealing materials.

2. A device for measuring compression of a visualizing seal according to claim 1, characterized in that: The categories of the upper assembly flange (2) and the lower assembly flange (4) include flat flanges, protruding flanges, concave-convex flanges and mortise flanges.

3. A device for measuring compression of a visualizing seal according to claim 2, characterized in that: The sealing materials of the standard color comparison strip (6) include flexible graphite, polytetrafluoroethylene, rubber, carbon fiber, copper, aluminum and stainless steel.

4. A device for measuring compression of a visualizing seal according to claim 3, characterized in that: In order to prevent abnormal damage of the sealing element (3) in the fastening process, the position and force of the fastening bolt (1) and the fastening nut (5) must be adjusted in real time according to the color change of the sealing element (3); after fastening is completed, the final color of the sealing element (3) is confirmed to be consistent with the color within the required compression rate range on the standard color comparison strip (6), and the fastening work of the sealing element (3) is completed.

5. A method of measuring a visualizing seal compression rate measuring device according to claim 4, characterized in that: The method comprises the following steps: Step 1: disassemble the connected flanges and old sealing gaskets on the system pipeline, and clean the sealing gasket installation position; Step 2: block the sealing part of the upper assembly flange (2) and the lower assembly flange (4), measure the specific size of the sealing element (3) installation position of the upper assembly flange (2) and the lower assembly flange (4), determine the size of the sealing element (3) and make the sealing gasket; Step 3: trim the sealing gasket, adjust the gap and concentricity between the upper assembly flange (2) and the lower assembly flange (4), and check and clean the sealing gasket installation position; Step 4: install the sealing gasket, the fastening bolt (1) and the fastening nut (5); Step 5: preliminarily fasten the upper assembly flange (2) and the lower assembly flange (4), and record the initial color of the sealing element (3); Step 6: fasten the sealing gasket and determine the compression rate.

6. A method of measuring compression of a visualizing seal according to claim 5, wherein: The step 1 comprises the following steps: Step 1.1: after the system pipeline is isolated, place a water receiving device at the upper assembly flange (2) and the lower assembly flange (4), and loosen the fastening bolt (1) and the fastening nut (5); Step 1.2: separate the upper assembly flange (2) from the lower assembly flange (4), remove the sealing element (3), block the pipe opening of the lower assembly flange (4), clean foreign matters on the sealing element (3) and store it; Step 1.3: clean and repair the sealing part of the upper assembly flange (2) and the lower assembly flange (4).

7. A method of measuring compression of a visualizing seal according to claim 6, wherein: The step 2 comprises the following steps: Step 2.1: clean and repair the sealing element (3) installation position between the upper assembly flange (2) and the lower assembly flange (4), remove the blockage of the lower assembly flange (4), and use a special anti-foreign matter block plate to block the upper assembly flange (2) and the lower assembly flange (4); Step 2.

2. Select the material of the sealing element (3) according to the operating conditions of the system, and make the sealing gasket according to the size of the sealing element (3) between the upper assembly flange (2) and the lower assembly flange (4).

8. A method of measuring compression of a visualizing seal according to claim 7, wherein: For different types of flanges, the size requirements of the sealing element (3) are different, including: (1) flat / convex flange Gasket outer diameter = bolt hole pitch circle diameter - bolt diameter - 1mm; Gasket inner diameter = assembly flange inner diameter + 2mm; (2) concave / convex flange Gasket outer diameter = concave diameter - 2mm; Gasket inner diameter = assembly flange inner diameter + 2mm; (3) tongue and groove flange Gasket outer diameter = groove major diameter - 2mm; Gasket inner diameter = groove minor diameter + 2mm.

9. A method of measuring compression of a visualizing seal according to claim 8, wherein: The step 3 includes the following steps: Step 3.1 Repair the inner and outer circular edge angles of the completed sealing element (3); Step 3.2 Measure the gap between the upper assembly flange (2) and the lower assembly flange (4) without installing the sealing element (3), so that the gap is not greater than the thickness of the sealing element (3) + 1mm, and adjust the fastening bolts (1) and nuts in time; Step 3.3 Measure the concentricity of the upper assembly flange (2) and the lower assembly flange (4); Step 3.4 Remove the anti-foreign matter baffle at the upper assembly flange (2) and the lower assembly flange (4), and clean the sealing surface.

10. A method of measuring compression of a visualizing seal according to claim 9, wherein: The step 4 includes the following steps: Step 4.1 Insert part of the fastening bolts (1) into the upper assembly flange (2) and the lower assembly flange (4), and place the newly made sealing element (3) into the upper assembly flange (2) and the lower assembly flange (4); Step 4.2 Insert the remaining fastening bolts (1) into the upper assembly flange (2) and the lower assembly flange (4), and screw the fastening nuts (5) into the fastening bolts (1) from the lower assembly flange (4).

11. A method of measuring compression of a visualizing seal according to claim 10, wherein: The step 5 includes the following steps: Step 5.1 Fix the upper assembly flange (2) and the fastening bolts (1), rotate the fastening nuts (5) below the lower assembly flange (4), and check the contact between the sealing element (3) and the lower contact surface of the upper assembly flange (2) and the upper contact surface of the lower assembly flange (4); Step 5.2 Record the initial color of the sealing element (3).

12. A method of measuring compression of a visualizing seal according to claim 11, wherein: The step 6 includes the following steps: Step 6.1 Symmetrically tighten the fastening nuts (5) according to the cross method, fix the fastening bolts (1) and tighten the fastening nuts (5), record the color of the sealing element (3) after tightening, compare the recorded color with the standard color contrast band (6), and record the compression rate of the sealing element (3) after this tightening; Step 6.2 If the compression rate does not meet the compression rate requirement of the sealing gasket of this material, repeat step 6.2 and record the color of the sealing element (3) until the compression rate of the sealing gasket after compression meets the standard requirement.

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