A method of flange sealing

Abstract

The present disclosure relates to a flange sealing method, the flange has a sealing surface, the sealing surface comprises a plurality of sides, the plurality of sides comprises straight sides and corner sides connected between two adjacent straight sides, each side is provided with a bolt hole for installing a bolt; the flange sealing method comprises: dividing the sealing surface into a plurality of sub-regions, wherein the straight sides and the corner sides are divided in different sub-regions; sorting the plurality of sub-regions, wherein the sorting rule of the plurality of sub-regions is configured as: the serial number of the sub-region corresponding to the straight side is smaller than the serial number of the sub-region corresponding to the corner side; and applying a tightening torque to the bolts of each sub-region in turn according to the serial numbers of the plurality of sub-regions in the order from small to large. The flange sealing method provided by the present disclosure can improve the sealing effect of the flange.

Description

Technical Field

[0001] This disclosure relates to the field of vacuum equipment sealing, and more particularly to a flange sealing method. Background Technology

[0002] With the widespread application of vacuum technology in new energy, new materials, space, biology, and other scientific and technological fields, vacuum devices often have complex structures and numerous interfaces with the outside world. For example, they frequently require the installation of particle detection equipment, ion emission equipment, and electron beam emission equipment. To ensure the normal operation of the entire vacuum device, the chamber that generates and maintains plasma operation must be a sealed, ultra-high vacuum environment with a vacuum level reaching a certain order of magnitude. Therefore, ensuring proper sealing of the vacuum device is of paramount importance. Summary of the Invention

[0003] This disclosure provides a flange sealing method to address the problems existing in the prior art, thereby improving the flange sealing effect.

[0004] According to a first aspect of this disclosure, a flange sealing method is provided, wherein the flange has a sealing surface, the sealing surface including a plurality of sides, the plurality of sides including straight sides and corner sides connecting two adjacent straight sides, and each side having a threaded hole for a bolt; the method includes:

[0005] The sealing surface is divided into multiple sub-regions, wherein the straight side and the corner side are divided into different sub-regions;

[0006] Multiple sub-regions are sorted, and the sorting rule for the multiple sub-regions is configured as follows: the sequence number of the sub-region corresponding to the straight side is less than the sequence number of the sub-region corresponding to the corner side;

[0007] Tightening torque is applied to the bolts in each sub-region in ascending order of their sorting numbers.

[0008] In one embodiment of this disclosure, the sealing surface is divided into multiple sub-regions, specifically including: two straight sides arranged opposite each other among the multiple sides are called a pair of opposite sides, and two corner sides arranged along the diagonal of the sealing surface are called a pair of opposite corners, each pair of opposite sides corresponds to a sub-region, and each pair of opposite corners corresponds to a sub-region.

[0009] In one embodiment of this disclosure, the sorting rules for the multiple sub-regions are configured as follows: among at least two sub-regions corresponding to the straight side, the longer the longest length of the straight side, the smaller the sequence number of the sub-region; and / or, among at least two sub-regions corresponding to the corner side, the longer the longest length of the corner side, the smaller the sequence number of the sub-region.

[0010] In one embodiment of this disclosure, the step of applying tightening torque to the bolts in each sub-region in ascending order of their sorting numbers specifically includes: when applying tightening torque to the bolts in any sub-region, applying tightening force to each bolt in that sub-region in ascending order of their bolt hole numbers.

[0011] In one embodiment of this disclosure, the screw hole numbering rule for any sub-region is configured as follows: screw holes on each side are numbered from small to large along the direction from the center position to both sides, and the screw holes on different sides are numbered alternately, and two screw holes on each side that are symmetrical about the center position of that side are numbered adjacently.

[0012] In one embodiment of this disclosure, the screw hole numbering rule for any sub-region is further configured as follows: when the number of screw holes on any side is odd, there is a central screw hole at the center of that side, and the central screw hole has the smallest number on that side; when the number of screw holes on any side is even, there are two central screw holes at the center of that side, and the two central screw holes have the smallest number on that side and are adjacent in number.

[0013] In one embodiment of this disclosure, one of the two sides in any sub-region is designated as the first side and the other side as the second side; the screw hole numbering rule for any sub-region is specifically configured as follows:

[0014] When the number of screw holes on both the first and second sides is odd.

[0015] The center screw hole located at the center position on the first side is numbered 1, and the center screw hole located at the center position on the second side is numbered 2;

[0016] On the first side, with the first screw hole as the center of symmetry, there are two screw holes that are symmetrical about the center of symmetry and are n hole distances away from the first screw hole. One screw hole is numbered N and the other screw hole is numbered (N+1).

[0017] On the second side, with the second screw hole as the center of symmetry, among the two screw holes that are symmetrical about the center of symmetry and are n hole distances away from the second screw hole, one screw hole is numbered (N+2) and the other screw hole is numbered (N+3).

[0018] Where N = 4n - 1, and n is an integer greater than or equal to 1.

[0019] In one embodiment of this disclosure, one of the two sides in any sub-region is designated as the first side and the other side as the second side; the screw hole numbering rule for any sub-region is specifically configured as follows:

[0020] When the number of screw holes on both the first and second sides is even.

[0021] The two central screw holes located at the center position on the first side are numbered 1 and 2 respectively, and the two central screw holes located at the center position on the second side are numbered 3 and 4 respectively;

[0022] On the first side, with the midpoint between the center screw hole numbered 1 and the center screw hole numbered 2 as the center of symmetry, among the two screw holes symmetrical about this center of symmetry, one screw hole is n holes away from the screw hole numbered 1, and is numbered N; the other screw hole is n holes away from the screw hole numbered 2, and is numbered (N+1).

[0023] On the second side, with the midpoint between the center screw hole numbered 3 and the center screw hole numbered 4 as the center of symmetry, among the two screw holes symmetrical about this center of symmetry, one screw hole is n holes away from the screw hole numbered 3, and is numbered (N+2), and the other screw hole is n holes away from the screw hole numbered 4, and is numbered (N+3).

[0024] Where N = 4n + 1, and n is an integer greater than or equal to 1.

[0025] In one embodiment of this disclosure, one of the two sides in any sub-region is designated as the first side and the other side as the second side; the screw hole numbering rule for any sub-region is specifically configured as follows:

[0026] When the number of screw holes on the first side is odd and the number of screw holes on the second side is even.

[0027] The center screw hole located at the center position on the first side is numbered 1, and the two center screw holes located at the center position on the second side are numbered 2 and 3 respectively;

[0028] On the first side, with the first screw hole as the center of symmetry, among the two screw holes that are symmetrical about the center of symmetry and are n hole distances away from the first screw hole, one screw hole is numbered N and the other screw hole is numbered (N+1).

[0029] On the second side, taking the midpoint between the screw hole numbered 2 and the screw hole numbered 3 as the center of symmetry, among the two screw holes symmetrical about this center of symmetry, one screw hole is n holes away from the screw hole numbered 2, and is numbered (N+2), and the other screw hole is n holes away from the screw hole numbered 3, and is numbered (N+3).

[0030] Where N = 4n, and n is an integer greater than or equal to 1.

[0031] In one embodiment of this disclosure, one of the two sides in any sub-region is designated as the first side and the other side as the second side; the screw hole numbering rule for any sub-region is specifically configured as follows:

[0032] When the number of screw holes on the first side is even and the number of screw holes on the second side is odd.

[0033] The two central screw holes located at the center of the first side are numbered 1 and 2 respectively; the central screw hole located at the center of the second side is numbered 3.

[0034] On the first side, the midpoint between the center screw hole numbered 1 and the center screw hole numbered 2 is taken as the center of symmetry. Among the two screw holes symmetrical about this center of symmetry, one screw hole is n holes away from the screw hole numbered 1, and is numbered N. The other screw hole is n holes away from the screw hole numbered 2, and is numbered (N+1).

[0035] On the second side, with the screw hole numbered 3 as the center of symmetry, among the two screw holes that are symmetrical about this center of symmetry and are n hole distances away from the screw hole numbered 3, one screw hole is numbered (N+2) and the other screw hole is numbered (N+3).

[0036] Where N = 4n, and n is an integer greater than or equal to 1.

[0037] In one embodiment of this disclosure, step 1, applying tightening torque to the bolts in each sub-region sequentially according to their sorting numbers from smallest to largest, specifically includes:

[0038] Each tightening step involves tightening all the bolts on the sides at least once, in ascending order of the sorting numbers of the multiple sub-regions. This tightening step is performed at least twice, and the tightening torque is increased by a preset torque value each time the tightening step is performed, until the tightening torque reaches a threshold value.

[0039] In one embodiment of this disclosure, performing the tightening step at least twice specifically includes:

[0040] When performing the above tightening step i1, all bolts on the straight sides are tightened at least once according to the sorting sequence number of the multiple sub-regions from small to large. For each tightening, the tightening torque increases by a preset torque value until the tightening torque reaches the first torque value. Then, a pre-tightening torque is applied to all bolts on the corner sides, wherein the pre-tightening torque is less than the first torque value, and i1 is an integer greater than or equal to 1.

[0041] In one embodiment of this disclosure, performing the tightening step at least twice further includes:

[0042] When performing the above tightening step for the i2th time, all bolts on the straight side are tightened at least once according to the sorting sequence number of the multiple sub-regions from small to large. Each time the bolt is tightened, the tightening torque increases by a preset torque value until the tightening torque reaches the second torque value from the first torque value. Then, all bolts on the side are tightened at least once according to the sorting sequence number of the multiple sub-regions from small to large. Each time the bolt is tightened, the tightening torque increases by a preset torque value until the tightening torque on all bolts reaches the threshold value. i2 is an integer greater than i1.

[0043] In one embodiment of this disclosure, after applying tightening torque to the bolts in each sub-region in ascending order of their sorting numbers, the method further includes:

[0044] When the tightening torque reaches the threshold, a leak detection step is performed to determine the number and location of leak points.

[0045] When the number of leak points is 1, a tightening torque is applied to the bolt at the position corresponding to the leak point. If the tightening torque is greater than or equal to the third threshold, a tightening torque is applied to the bolt at the position adjacent to the leak point.

[0046] When the number of leaks is greater than 1, repeat the tightening steps and the leak detection steps described above until the number of leaks is less than or equal to 1.

[0047] One beneficial effect of this disclosure is that, in this flange sealing method, when tightening the bolts on each side of the flange, the sealing surface of the flange is divided into multiple sub-regions. The straight sides and corner sides of the flange are divided into different sub-regions, and these sub-regions are ordered, with the sub-region corresponding to the straight side having a lower sequence number than the sub-region corresponding to the corner side. The sub-regions are tightened sequentially according to the ascending sequence number. Thus, during flange sealing, the flange can be fastened to the vacuum equipment and waiting sealing element in the order of straight sides first, then corner sides, meeting the airtightness requirements during actual flange installation and achieving a high flange sealing effect.

[0048] Other features and advantages of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0049] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the present disclosure and, together with their description, serve to explain the principles of the present disclosure.

[0050] Figure 1 This is a schematic diagram of a stepped flat flange sealing structure;

[0051] Figure 2This is a flowchart of a flange sealing method provided in one embodiment of this disclosure;

[0052] Figure 3 This is a schematic diagram of the bolt hole numbering when the flange sealing method provided in one embodiment of this disclosure is applied to a trapezoidal flange;

[0053] Figure 4 This is a schematic diagram of the bolt hole numbering when the flange sealing method provided in one embodiment of this disclosure is applied to a runway flange;

[0054] Figure 5 This is a schematic diagram of the bolt hole numbering when the flange sealing method provided in one embodiment of this disclosure is applied to a rectangular flange.

[0055] Figures 1 to 5 The one-to-one correspondence between the component names and the reference numerals in the figures is as follows:

[0056] 10. Flange; 10A. Sealing surface; 10A1. First sealing surface; 10A2. Second sealing surface; 20. Sealing ring; A. Screw hole; S1. Straight side; S11. First straight side; S12. Second straight side; S13. Third straight side; S14. Fourth straight side; S2. Corner side; S21. First corner side; S22. Second corner side; S23. Third corner side; S24. Fourth corner side. Detailed Implementation

[0057] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present disclosure.

[0058] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this disclosure or its application or use.

[0059] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0060] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0061] The specific embodiments of this disclosure are described below with reference to the accompanying drawings.

[0062] In this article, terms such as "up," "down," "front," "back," "left," and "right" are used only to indicate the relative positional relationship between related parts, rather than to define the absolute position of these related parts.

[0063] In this article, "first," "second," etc., are used only to distinguish one another, and not to indicate degree of importance, order, or prerequisite for each other.

[0064] In this document, terms such as “equal” and “same” are not strict mathematical and / or geometric limitations, but also include errors that are understandable to those skilled in the art and permissible in manufacturing or use.

[0065] Before providing a detailed description of the flange sealing method provided in the embodiments of this disclosure, the following description of the related technology is provided:

[0066] In related technologies, vacuum seals, based on the material of the sealing ring, are mainly classified into seals made of synthetic materials such as rubber, polytetrafluoroethylene, and polyurethane, as well as metal seals.

[0067] Rubber and synthetic materials possess advantages such as high elasticity, high wear resistance, and suitable mechanical strength, making them widely used in vacuum sealing. However, their applications are limited due to their high gas escaping and permeability rates, as well as their inability to withstand high-temperature baking and radiation.

[0068] Metal seals overcome the shortcomings of rubber seals and are therefore widely used in ultra-high vacuum environments. Metal seals achieve sealing by plastically deforming an elastic metal sealing ring to fill the flange sealing surface. Because metal materials possess a certain degree of elasticity and ductility, they can be used for sealing various vacuum and pressure equipment.

[0069] Elastic metal sealing rings used in metal sealing structures can be made of relatively soft metals such as oxygen-free copper, pure aluminum, gold, and silver. In addition, some metals with good ductility, such as indium, can flow in all directions under external pressure, filling gaps in the sealing surface and also achieving a sealing effect.

[0070] For ultra-high vacuum, the leakage rate is generally required to be less than 1×10⁻⁶. -11 Pa·m 3 / s. For better sealing, the surface roughness Ra of the flange sealing surface is generally required to be ≤0.8. Compared to rubber seals, metal seals have relatively poor plasticity, leading to greater sealing difficulty. This is especially true when the window shape of the vacuum equipment is non-standard circular, making sealing even more challenging. Therefore, a reliable flange sealing method is needed to meet the high leakage rate requirements of the vacuum chamber.

[0071] To address the aforementioned issues, this disclosure provides a flange sealing method that improves flange sealing performance and meets the airtightness requirements of various vacuum and pressure equipment.

[0072] Metal sealing structures mainly include flat flange sealing structures, knife-edge flange sealing structures, and wedge flange sealing structures. For knife-edge and wedge flange sealing structures, a precision pointed structure is provided on the flange sealing surface. This pointed structure can penetrate the sealing ring to achieve a good seal. However, for large vacuum devices (such as controlled nuclear fusion devices), the pointed structure on the flange sealing surface is relatively thin and easily damaged. Damage to this structure can cause significant losses, and repairs are troublesome and expensive. The sealing surface of a flat flange can be repaired through simple grinding. However, flat flange sealing structures, especially non-standard circular flat flanges, present airtightness issues during installation.

[0073] The flange sealing method provided in this disclosure can be applied to flat flange sealing scenarios to solve the airtightness problem during the actual installation of flat flanges (especially non-standard circular flat flanges).

[0074] The flange sealing method provided in this disclosure is applicable to, but not limited to, flat flange sealing using stepped plane sealing. The flange sealing method provided in this disclosure can be applied to non-standard circular flanges, such as trapezoidal flanges, racetrack flanges, and rectangular flanges.

[0075] Please see Figure 1 As shown, in one embodiment of this disclosure, the flange 10 has a sealing surface 10A, and the sealing surface 10A is configured to have a stepped sealing plane. That is, as Figure 1 As shown, the sealing surface 10A of the flange 10 may include a first sealing surface 10A1 and a second sealing surface 10A2. The first sealing surface 10A1 and the second sealing surface 10A2 have a discontinuity, making the sealing surface 10A as a whole stepped. When sealing the flange 10, a sealing ring 20 can be placed between the stepped sealing plane of the flange 10 and the part to be sealed (such as the interface of a vacuum device). The sealing ring 20 can be made of metal wire, and the sealing ring can be compressed or extended in all directions when subjected to force.

[0076] Through inventive effort, the applicant analyzed the airtightness problem of the existing flat flange 10 sealing structure and discovered that one reason for this problem is that uneven pressure on the flange 10 and the sealing ring during installation leads to undesirable deformation of the sealing ring due to uneven stress (e.g., slight bending, twisting, or curling of the sealing ring), resulting in poor airtightness. The flange sealing method provided in this disclosure improves the flange 10 installation process to minimize uneven stress on the flange 10 and the sealing ring, reducing undesirable deformation of the sealing ring and thus improving the airtightness of the flange 10 sealing structure.

[0077] Please see Figure 3 As shown, the sealing surface 10A of the flange 10 may include a plurality of side edges connected in sequence in a circumferential direction. The plurality of side edges may include at least one straight side edge S1 and a corner side edge S2 connected between two adjacent straight side edges S1. Each side edge may be provided with a screw hole A, and a bolt may be inserted into the screw hole A. By tightening the bolt, a sealing fit between the sealing surface 10A of the flange 10 and the sealing surface 10A of the part to be sealed is achieved.

[0078] The straight side S1 can be considered as the main side that encloses the edge pattern of the sealing surface 10A of the flange 10. That is, the shape enclosed by multiple straight side S1s is approximately the same as the overall pattern of the sealing surface of the flange 10. For example, for a rectangular or trapezoidal flange, the edge pattern of the sealing surface 10A is rectangular or trapezoidal, and the straight side S1 are the four sides that enclose the rectangular or trapezoidal pattern; for a racetrack flange, the straight side S1 is the side that extends along a straight line.

[0079] The corner side S2 can be considered as a non-linearly extending side with a curved or meandering shape, used to connect two adjacent straight sides, and can be located at the vertex of the edge pattern of the sealing surface of flange 10. For example, for a rectangular or trapezoidal flange, if the edge pattern of the sealing surface 10A is rectangular or trapezoidal, then the corner side S2 is the vertex of the rectangular or trapezoidal pattern; for a raceway flange, the corner side S2 is a non-linearly extending arc-shaped side.

[0080] like Figure 2 and Figure 3 As shown, the flange sealing method provided in this embodiment includes the following steps:

[0081] Step S01: Divide the sealing surface 10A into multiple sub-regions, wherein the straight side S1 and the corner side S2 are divided into different sub-regions;

[0082] Step S02: Sort multiple sub-regions, wherein the sorting rule for the multiple sub-regions is configured as follows: the sequence number of the sub-region corresponding to the straight side S1 is less than the sequence number of the sub-region corresponding to the corner side S2;

[0083] Step S03: Apply tightening torque to the bolts in each sub-region in ascending order of their sorting numbers.

[0084] In the above scheme, when tightening the bolts on each side of the flange 10, the sealing surface 10A of the flange 10 can be divided into multiple sub-regions according to the shape and distribution of the multiple sides of the flange 10. The straight side S1 and the corner side S2 of the flange 10 are divided into different sub-regions, and the multiple sub-regions are sorted. The sequence number of the sub-region corresponding to the straight side S1 is less than the sequence number of the sub-region corresponding to the corner side S2. The bolts of each sub-region are tightened in order from small to large sequence number. In this way, the flange 10 is fastened to the vacuum equipment waiting for the sealing element in the order of straight side S1 first and then corner side S2. During the tightening process, the sealing ring is compressed in the order of the position corresponding to the straight side S1 first and then the position corresponding to the corner side S2. This order can minimize the twisting and other adverse deformation of the sealing ring and ensure that the adverse deformation of the sealing ring does not occur on the straight side S1 as much as possible, so as to improve the airtightness of the flange 10.

[0085] In one embodiment of this disclosure, step S01 specifically includes: two straight sides S1 arranged opposite each other among the plurality of sides are designated as a pair of opposite sides, and two corner sides S2 arranged along the diagonal of the sealing surface 10A (i.e., located at two non-adjacent vertices of the edge pattern of the sealing surface 10A) are designated as a pair of opposite corners. Each pair of opposite sides corresponds to a sub-region, and each pair of opposite corners corresponds to a sub-region. In this way, during the installation of the flange 10, the two straight sides S1 of the same pair of opposite sides and the two corner sides S2 of the same pair of opposite corners can be tightened simultaneously to ensure that the sealing ring is subjected to uniform force.

[0086] In one embodiment of this disclosure, in step S02 above, the sorting rule for the multiple sub-regions is configured as follows: among at least two sub-regions corresponding to the straight side S1, the longer the longest length of the straight side S1, the smaller the sub-region number; and / or, among at least two sub-regions corresponding to the corner side S2, the longer the longest length of the corner side S2, the smaller the sub-region number. Since a longer side length increases the probability of the sealing ring undergoing twisting or other undesirable deformation, tightening the bolts on the longer side before the shorter side can minimize airtightness issues.

[0087] For example, such as Figure 3In one embodiment shown, the flange 10 is a trapezoidal flange, which may include four straight sides S1 and four corner sides S2. The four straight sides S1 are divided into two sets of opposite sides. One set of opposite sides is constructed as the upper and lower bases of a trapezoid, namely the first straight side S11 and the second straight side S12, where the first straight side S11 is longer than the second straight side S12. The other set of opposite sides is constructed as the legs of a trapezoid, namely the third straight side S13 and the fourth straight side S14, where the third straight side S13 and the fourth straight side S14 are of equal length. The two sets of opposite sides can be divided into two sub-regions respectively. Figure 3 As shown in the example, the length of the first straight side S11 is less than the length of the third straight side S13. Therefore, the sequence number of the sub-region corresponding to the first straight side S11 can be less than the sequence number of the sub-region corresponding to the third straight side S13. That is to say, during the installation of flange 10, the bolts on the left and right straight sides can be tightened first, and then the bolts on the upper and lower straight sides can be tightened.

[0088] In one embodiment of this disclosure, step S03 specifically includes:

[0089] Step S031: Number the screw holes A in each sub-region;

[0090] Step S032: When applying tightening torque to the bolts in any sub-region, tightening force is applied sequentially to each bolt in that sub-region in ascending order of bolt hole number.

[0091] The above scheme involves tightening the bolts in each sub-region sequentially according to the ascending order of their arrangement numbers; and for each sub-region, tightening the bolts sequentially according to the ascending order of the bolt hole A numbers within that sub-region.

[0092] In one embodiment of this disclosure, in step S031 above, the screw hole numbering rule for any sub-region is configured as follows: screw holes A are numbered from small to large along the direction from the center position to both sides of each side, and screw holes A are numbered alternately between different sides, and two screw holes A on each side that are symmetrical about the center position of that side are numbered adjacently.

[0093] In the above scheme, the bolts on each side are numbered from smallest to largest, starting from the center and moving outwards. This means that for each side, the bolt tightening sequence is from the center outwards, and the sealing ring is stressed accordingly from the center outwards. In other words, the sealing ring is pushed from the center outwards to ensure it gradually stretches from the center to the ends, reducing twisting and other undesirable deformations. Furthermore, the bolt holes A on different sides are staggered. This allows for staggered tightening of bolts on opposite sides during flange 10 installation, resulting in more even pressure on opposite sides or diagonally. Additionally, the two bolt holes A symmetrically located about the center of each side are numbered adjacently. This allows for symmetrical tightening of the two bolt holes A symmetrically located about the center of each side, ensuring even stress distribution on both sides of that side.

[0094] In one embodiment of this disclosure, the screw hole numbering rule for any sub-region is further configured as follows: when the number of screw holes A on any side is odd, there is one central screw hole at the center of that side, and the central screw hole has the smallest number on that side; when the number of screw holes A on any side is even, there are two central screw holes at the center of that side, and the two central screw holes have the smallest number on that side and are adjacent in number. This ensures that each side experiences uniform stress during bolt tightening.

[0095] In one embodiment of this disclosure, the screw hole numbering rule for any sub-region is specifically configured as follows: one side is designated as the first side, and the other side as the second side. The length of the first side is greater than or equal to the length of the second side. A screw hole A at the center position of the first side is numbered as 1. Thus, the screw hole A is numbered sequentially from 1 to 1, 2, 3, and so on. When the lengths of two sides in the same sub-region are unequal, the screw hole A at the center position of the longer side is numbered as 1. That is, the bolt at the center position of the longer side is screwed in first.

[0096] It is understandable that the numbering rule for screw hole A in any sub-region is not limited to assigning the center screw hole of the longer side as number 1; it could also be assigned the center screw hole of the shorter side as number 1. For example, Figure 3 In the embodiment shown, the first corner side S21 is shorter than the second corner side S22 in a set of diagonals, and the shorter first corner side S21 can be numbered as 1.

[0097] The following examples illustrate the numbering sequence of screw holes A within each sub-region.

[0098] In one embodiment of this disclosure, the numbering rule for screw holes A in any sub-region is specifically configured as follows: when the number of screw holes A on both the first side and the second side is odd, the center screw hole located at the center position on the first side is numbered 1, and the center screw hole located at the center position on the second side is numbered 2; on the first side, with the center screw hole numbered 1 as the center of symmetry, among the two screw holes A that are symmetrical about the center of symmetry and are n hole distances away from the center screw hole numbered 1, one screw hole A is numbered N, and the other screw hole A is numbered (N+1); on the second side, with the center screw hole numbered 2 as the center of symmetry, among the two screw holes A that are symmetrical about the center of symmetry and are n hole distances away from the screw hole numbered 2, one screw hole A is numbered (N+2), and the other screw hole A is numbered (N+3); where N = 4n - 1, and n is an integer greater than or equal to 1.

[0099] The following describes the numbering order in the above embodiments with reference to a specific example.

[0100] Please see Figure 4 Taking the example shown, the first straight side S11 and the second straight side S12 are divided into a sub-region. The first straight side S11 is the first side, and the second straight side S12 is the second side. There are 9 screw holes A distributed on the first straight side S11 and 9 screw holes A distributed on the second straight side S12. The center screw hole at the center position of the first straight side S11 is numbered 1, and the center screw hole at the center position of the second straight side S12 is numbered 2. The distance from the center of the first straight side S11... The two screw holes A with a spacing of 1 hole are numbered 3 and 4 respectively. The two screw holes A on the second straight side S12 with a spacing of 1 hole from the center screw hole are numbered 5 and 6 respectively. And so on. Finally, the numbers of the nine screw holes A on the first straight side S11 from one end to the other are: 15, 11, 7, 3, 1, 4, 8, 12 and 16 respectively. The numbers of the nine screw holes A on the second straight side S12 from one end to the other are: 17, 13, 9, 5, 2, 6, 10, 14 and 18 respectively.

[0101] In another embodiment of this disclosure, the numbering rule for screw holes A in any sub-region is specifically configured as follows: when the number of screw holes A on both the first side and the second side is even, the two central screw holes located at the center position on the first side are numbered 1 and 2 respectively, and the two central screw holes located at the center position on the second side are numbered 3 and 4 respectively; on the first side, taking the midpoint between the central screw hole numbered 1 and the central screw hole numbered 2 as the center of symmetry, among the two screw holes A symmetrical about this center of symmetry, one screw hole A is symmetrical to the screw hole numbered 1. Screw hole A is n holes apart, denoted as N. Another screw hole A is n holes apart from screw hole A numbered 2, denoted as (N+1). On the second side, taking the midpoint between the center screw hole numbered 3 and the center screw hole numbered 4 as the center of symmetry, among the two screw holes A symmetrical about this center of symmetry, one screw hole A is n holes apart from screw hole A numbered 3, denoted as (N+2), and the other screw hole A is n holes apart from screw hole A numbered 4, denoted as (N+3). Wherein, N = 4n + 1, and n is an integer greater than or equal to 1.

[0102] The following describes the numbering order in the above embodiments with reference to a specific example.

[0103] Please see Figure 3 Taking the example shown, the opposite third straight side S13 and fourth straight side S14 are divided into a sub-region. The third straight side S13 is the first side, and the fourth straight side S14 is the second side. Six screw holes A are distributed on the third straight side S13, and six screw holes A are distributed on the fourth straight side S14. The two central screw holes at the center of the third straight side S13 are numbered 1 and 2, and the two central screw holes at the center of the fourth straight side S14 are numbered 3 and 4. The two screw holes A on the third straight side S13, which are one hole distance from the center screw hole, are numbered 5 and 6 respectively. The two screw holes A on the fourth straight side S14, which are one hole distance from the center screw hole, are numbered 7 and 8 respectively, and so on. Finally, the six screw holes A on the third straight side S13 are numbered from one end to the other as follows: 9, 5, 1, 2, 6, 10; and the six screw holes A on the fourth straight side S14 are numbered from one end to the other as follows: 12, 8, 4, 3, 7, 11.

[0104] In another embodiment of this disclosure, the numbering rule for screw holes A in any sub-region is specifically configured as follows: when the number of screw holes A on the first side is odd and the number of screw holes A on the second side is even, the center screw hole located at the center position on the first side is numbered 1, and the two center screw holes located at the center position on the second side are numbered 2 and 3 respectively; on the first side, taking the center screw hole numbered 1 as the center of symmetry, two screw holes A numbered 1 that are symmetrical about this center of symmetry and are n hole distances away from the screw hole A numbered 1 are... Of the screw holes A, one screw hole A is numbered N, and the other screw hole A is numbered (N+1). On the second side, taking the midpoint between the second screw hole A and the third screw hole A as the center of symmetry, among the two screw holes A symmetrical about this center of symmetry, one screw hole A is n holes away from the second screw hole A and is numbered (N+2), and the other screw hole A is n holes away from the third screw hole A and is numbered (N+3). Where N = 4n, and n is an integer greater than or equal to 1.

[0105] It should be noted that when the number of screw holes A on the first side and the second side are not equal, for example, there are m1 screw holes A on the first side and m2 screw holes A on the second side, where m1 is greater than m2, the screw holes A on the two sides can be numbered alternately according to the above numbering order until the m2 screw holes A on each side are numbered. The remaining (m1-m2) screw holes A can be numbered according to the rule that the two screw holes A that are symmetrical about the center are numbered adjacently and the numbering gradually increases from the middle of the side to both sides.

[0106] The following describes the numbering order in the above embodiments with reference to a specific example.

[0107] Please see Figure 3 Taking the example shown, the first straight side S11 and the second straight side S12 are divided into a sub-region. The first straight side S11 is the first side, and the second straight side S12 is the second side. There are 5 screw holes A distributed on the first straight side S11 and 2 screw holes A distributed on the second straight side S12. The center screw hole at the center of the first straight side S11 is numbered 1, and the two center screw holes at the center of the second straight side S12 are numbered 2 and 3. The two screw holes A on the first straight side S11 that are 1 hole distance away from the center screw hole are numbered 4 and 5 respectively. Since there are no extra screw holes A on the second straight side S12, the screw holes A on the first straight side S11 can be numbered 7 and 8 in sequence. Finally, the five screw holes A on the first straight side S11 are numbered sequentially from one end to the other as 6, 4, 1, 5, and 7; the two screw holes A on the second straight side S12 are numbered sequentially from one end to the other as 2 and 3.

[0108] In another embodiment of this disclosure, the numbering rule for screw holes A in any sub-region is specifically configured as follows: when the number of screw holes A on the first side is even and the number of screw holes A on the second side is odd, the two central screw holes located at the center position on the first side are numbered 1 and 2 respectively; the central screw hole located at the center position on the second side is numbered 3; on the first side, taking the midpoint between the central screw hole numbered 1 and the central screw hole numbered 2 as the center of symmetry, two screw holes symmetrical about this center of symmetry are... In hole A, one screw hole A is n holes away from the screw hole A numbered 1, and is numbered N. The other screw hole A is n holes away from the screw hole A numbered 2, and is numbered (N+1). On the second side, with the screw hole A numbered 3 as the center of symmetry, among the two screw holes A that are symmetrical about the center of symmetry and n holes away from the screw hole A numbered 3, one screw hole A is numbered (N+2) and the other screw hole A is numbered (N+3). Wherein, N = 4n, and n is an integer greater than or equal to 1.

[0109] The following describes the numbering order in the above embodiments with reference to a specific example.

[0110] The first side and the second side are opposite each other and are divided into the same sub-region. There are 6 screw holes A on the first side and 3 screw holes A on the second side. The two central screw holes at the center of the first side are numbered 1 and 2, the central screw hole at the center of the second side is numbered 3, the two screw holes A on the first side that are one hole distance from the central screw hole are numbered 4 and 5, the two screw holes A on the second side that are one hole distance from the central screw hole are numbered 6 and 7, and so on. The two screw holes A on the first side that are two hole distances from the central screw hole are numbered 8 and 9. Therefore, the six screw holes A on the first side are numbered 8, 4, 1, 2, 5, 9 from one end to the other; the two screw holes A on the second side are numbered 6, 3, 7 from one end to the other.

[0111] In one embodiment of this disclosure, step S032 specifically includes:

[0112] Each tightening step involves tightening all the bolts on the sides at least once, in ascending order of the sorting numbers of the multiple sub-regions. This tightening step is performed at least twice, and the tightening torque is increased by a preset torque value each time the tightening step is performed, until the tightening torque reaches a threshold M.

[0113] In the above scheme, the tightening step refers to the process of tightening all the bolts on the sides of the sealing surface 10A once, according to the sequence number of the multiple sub-regions. Therefore, the tightening step can also be called the step of tightening all the bolts on the sealing surface 10A one turn.

[0114] Perform the tightening steps described above at least twice. That is, during the installation of flange 10, all bolts on sealing surface 10A should be tightened at least 2 turns, and for each additional turn, the tightening torque should be increased by a preset torque value. In this way, the tightening force is gradually increased to the threshold M. Compared with the method of increasing the tightening force to the threshold M on the bolts all at once, this method is more conducive to uniform force distribution and reduces adverse deformations such as twisting of the sealing ring.

[0115] In one embodiment of this disclosure, step S032, which involves performing the tightening step at least twice, specifically includes:

[0116] Step S0321: When performing the above tightening step for the i1th time, according to the sorting sequence number of the multiple sub-regions from small to large, tighten all the bolts on the straight side S1 at least once, and each time the bolt is tightened, the tightening torque increases by a preset torque value until the tightening torque reaches the first torque value M1. Then, apply a pre-tightening torque to the bolts on all the corner side S2, wherein the pre-tightening torque is less than the first torque value M1, and i1 is an integer greater than or equal to 1.

[0117] In the above scheme, during the installation of flange 10, when performing the i1st tightening step (i.e., the i1st turn of tightening the bolts), all bolts on the straight side S1 can be tightened once or multiple times until the tightening torque of the bolts on the straight side S1 reaches the first torque value M1. At this time, all bolts on the corner side S2 are pre-tightened. In this way, the first tightening step of tightening all bolts on the sealing surface 10A once is completed.

[0118] It should be noted that the pre-tightening torque is less than the first torque value M1. The magnitude of the pre-tightening torque can be understood as the amount by which the operator manually tightens the bolt on the corner side S2 slightly.

[0119] It should also be noted that during the execution of the sub-steps, the gap between the flange 10 and the part to be sealed can be observed with the naked eye to determine whether the sealing ring is subjected to uniform force during the installation of the flange 10.

[0120] In one embodiment of this disclosure, step S032, which involves performing the tightening step at least twice, further includes:

[0121] When performing the above tightening step for the i2th time, all bolts on the straight side S1 are tightened at least once according to the sorting sequence number of the multiple sub-regions from small to large. Each time the bolts are tightened, the tightening torque increases by a preset torque value until the tightening torque reaches the second torque value M2 from the first torque value M1. Then, all bolts on the side are tightened at least once according to the sorting sequence number of the multiple sub-regions from small to large. Each time the bolts are tightened, the tightening torque increases by a preset torque value until the tightening torque on all bolts reaches the threshold M, where i2 is an integer greater than i1.

[0122] In the above scheme, when performing the i2nd tightening step, first tighten all the bolts on the straight side S1 once or multiple times until the tightening torque of the bolts on the straight side S1 increases from the first torque value M1 to the second torque value M2. At this time, tighten all the bolts on the corner side S2 at least one turn until the torque on all bolts reaches the threshold M. In this way, all the bolts on the sealing surface 10A are tightened.

[0123] In one embodiment of this disclosure, after step S03 above, the method includes:

[0124] Step S04: When the tightening torque reaches the threshold M, a leak detection step is performed to determine the number and location of leak points. When the number of leak points is 1, a tightening torque is applied to the bolt at the corresponding position of the leak point. If the tightening torque is greater than or equal to the third threshold M3, a tightening torque is applied to the bolt at the position adjacent to the leak point. When the number of leak points is greater than 1, the above tightening step and the above leak detection step are repeated until the number of leak points is less than or equal to 1.

[0125] In the above scheme, when the tightening torque is at the threshold, a preliminary leak detection can be performed; if there is no leak, it indicates that the seal is good; if a single-point leak is detected, force is applied to the leak point until it is sealed, while the screws in other positions remain stationary during this process. However, if the third threshold M3 tightening torque is applied to the bolt at the leak point, the tightness of the screws around the leak point must be checked and tightened appropriately; if there are multiple leaks, the tightening steps are repeated multiple times, and the tightening torque is increased by the preset torque value for each additional tightening step, until a single-point leak or no leak at all is gradually achieved.

[0126] For ease of understanding, please refer to the following: Figures 3 to 5 The specific steps of the flange sealing method of this disclosure are described in detail with reference to several embodiments.

[0127] Example 1

[0128] Please see Figure 3As shown, the flange 10 is a trapezoidal flange, and the sealing surface 10A of the flange 10 includes four straight sides S1 and four corner sides S2. The four straight sides S1 are respectively a first straight side S11 and a second straight side S12, and a third straight side S13 and a fourth straight side S14, which are opposite each other. The four corner sides S2 are respectively a first corner side S21 and a second corner side S22, which are arranged along one diagonal of the sealing surface 10A, and a third corner side S23 and a fourth corner side S24, which are arranged along the other diagonal of the sealing surface 10A.

[0129] The flange sealing method provided in this disclosure, when applied to a trapezoidal flange, may include the following steps:

[0130] Step S01: Based on the shape and distribution of the multiple sides of the trapezoidal flange, divide the sealing surface 10A of the trapezoidal flange into 4 sub-regions;

[0131] In this step, the third straight side S13 and the fourth straight side S14 are divided into the first sub-region, the first straight side S11 and the second straight side S12 are divided into the second sub-region, the first corner side S21 and the second corner side S22 are divided into the third sub-region, and the third corner side S23 and the fourth corner side S24 are divided into the fourth sub-region.

[0132] Step S02: Sort the multiple sub-regions;

[0133] In this step, the longest length of the diagonal side is greater than the longest length of the parallel side, and the lengths of the two sets of diagonals are approximately the same. Therefore, the sorting number of the first sub-region is 1, the sorting number of the second sub-region is 2, the sorting number of the third sub-region is 3, and the sorting number of the fourth sub-region is 4.

[0134] Step S03: Apply tightening torque to the bolts in each sub-region in ascending order of their sorting numbers. When applying tightening torque to the bolts in any sub-region, apply tightening force to each bolt in that sub-region in ascending order of their bolt hole numbers.

[0135] This step specifically includes:

[0136] Step S031: Number the screw holes A in each sub-region. The numbering results for screw holes A are as follows:

[0137] For the first sub-region, the two sides are of equal length, and each side has 6 screw holes A. Therefore, according to the screw hole A numbering rule, the screw holes A on one side are numbered 9, 5, 1, 2, 6, 10, and the screw holes A on the other side are numbered 12, 8, 4, 3, 7, 11. For the second sub-region, the two sides are of unequal length. The longer side (i.e., the first straight side S11) has 5 screw holes A, and the shorter side (i.e., the second straight side S12) has 2 screw holes A. According to the screw hole A numbering rule, the screw holes A on the first straight side S11 are numbered 9, 5, 1, 2, 6, 10, and the screw holes A on the other side are numbered 12, 8, 4, 3, 7, 11, respectively. For the second straight side S12, the screw holes A are numbered 2 and 3 respectively, corresponding to 6, 4, 1, 5, and 7. For the third sub-region, the screw hole A on the shorter side (i.e., the first corner side S21) of the two corner sides S2 is 1, numbered 1, and the screw hole A on the longer side (i.e., the second corner side S22) is 2, numbered 2 and 3 respectively. For the fourth sub-region, the screw hole A on the shorter side (i.e., the third corner side S23) of the two corner sides S2 is 1, numbered 1, and the screw hole A on the longer side (i.e., the fourth corner side S24) is 2, numbered 2 and 3 respectively.

[0138] Step S032: Tighten the bolts of each sub-region in the order of their arrangement numbers from 1 to 4, and when tightening the bolt holes A in each sub-region, tighten the bolts in the order of the bolt hole A numbers from smallest to largest.

[0139] The above step S032 specifically includes: performing multiple tightening steps, and each time the above tightening step is performed, the tightening torque increases by a preset torque value until the tightening torque reaches a threshold M.

[0140] The above step S032 specifically includes the following steps:

[0141] Step S0321: Perform the first tightening step;

[0142] In this step, following the sequence of the sub-regions and the numbering of the screw holes A within each sub-region, all bolts on the straight side S1 are tightened at least once. For each turn of tightening, the tightening torque on all bolts on the straight side S1 increases by a preset torque value (e.g., 5 N*m), until the tightening torque on all bolts on the straight side S1 reaches a first torque value M1 (e.g., 20 N*m). Then, a pre-tightening torque is applied to the bolts on the corner side S2. This pre-tightening torque is less than the first torque value M1 (the application of the pre-tightening torque can be achieved by the operator slightly tightening the bolts by hand). In one embodiment, all bolts on the straight side S1 can be tightened 3-4 turns until the tightening torque on the bolts on the straight side S1 reaches 20 N*m, and then the bolts on the corner side S2 can be manually tightened.

[0143] Step S0322: Perform the above tightening step for the second time;

[0144] In this step, following the sequence of the sub-regions and the numbering of the screw holes A within each sub-region, all bolts on the straight side S1 are tightened at least once. For each turn of tightening, the tightening torque on all bolts on the straight side S1 increases by a preset torque value (e.g., 5 N*m), until the tightening torque on all bolts on the straight side S1 reaches a second torque value M2 (e.g., the first torque value M2 is 25 N*m). Then, tightening torque is applied to all bolts until the tightening torque reaches a threshold M, for example, 30 N*m. In one embodiment, in this step, all bolts on the straight side S1 can be tightened 0-1 turns first, and then the bolts on the corner side S2 can be tightened for the last 1-2 turns until the tightening torque on the corner side S2 reaches the threshold M.

[0145] It should be noted that during the above steps, the size of the gap between the sealing surface 10A of the flange 10 and the sealing surface 10A of the part to be sealed can be observed with the naked eye to determine whether the sealing ring is subjected to uniform force diagonally.

[0146] It should also be noted that in step S032 above, before performing multiple tightening steps, the flange 10 can be pre-pressurized. The specific process is as follows: the operator can first tighten the bolts by hand, roughly flatten the sealing ring, and then use a wrench to lightly tighten all the bolts once.

[0147] Furthermore, after step S03 above, the trapezoidal flange sealing method may also include:

[0148] Step S04: When the tightening torque is at the threshold value, a preliminary leak check can be performed. If there is no leak, it indicates that the seal is good. If a single-point leak is detected, apply force to the leak point until it is sealed. During this process, the screws in other positions remain stationary. However, if the third threshold value M3 is applied to the bolt at the leak point, the tightness of the screws around the leak point must be checked and tightened appropriately. If there are multiple leaks, repeat the tightening steps multiple times. For each additional tightening step, the tightening torque increases by a preset torque value until a single-point leak or no leak at all is gradually achieved.

[0149] Example 2

[0150] Please see Figure 4 As shown, the flange 10 is a raceway flange. The sealing surface 10A of the flange 10 includes two parallel straight sides S1 and two arc-shaped corner sides S2. The two parallel straight sides S1 are the first straight side S11 and the second straight side S12, respectively, and the two arc-shaped corner sides S2 are the first corner side S21 and the second corner side S22, respectively.

[0151] When the flange sealing method provided in this disclosure is applied to a runway flange, it may include the following steps:

[0152] Step S01: Based on the shape and distribution of the multiple sides of the runway flange, divide the sealing surface 10A of the runway flange into two sub-regions;

[0153] In this step, the first straight side S11 and the second straight side S12 are divided into the first sub-region, and the first corner side S21 and the second corner side S22 are divided into the second sub-region.

[0154] Step S02: Sort the multiple sub-regions;

[0155] In this step, the sorting number of the first sub-region is 1, and the sorting number of the second sub-region is 2;

[0156] Step S03: Apply tightening torque to the bolts in each sub-region in ascending order of their sorting numbers. When applying tightening torque to the bolts in any sub-region, apply tightening force to each bolt in that sub-region in ascending order of their bolt hole numbers.

[0157] Step S03 specifically includes:

[0158] Step S031: Number the screw holes A in each sub-region. The numbering results for screw holes A are as follows:

[0159] For the first sub-region, the first straight side S11 and the second straight side S12 have the same length, and there are 9 screw holes A distributed on each side. Therefore, according to the screw hole A numbering rule, the screw holes A on one side are numbered 15, 11, 7, 3, 1, 4, 8, 12, 16, and the screw holes A on the other side are numbered 17, 13, 9, 5, 2, 6, 10, 14, and 18, respectively. For the second sub-region, the first corner side S21 and the second corner side S22 have the same length, and there are 5 screw holes A distributed on each side. According to the screw hole A numbering rule, the screw holes A on one side are numbered 7, 3, 1, 4, 8, and the screw holes A on the other side are numbered 9, 5, 2, 6, 10, respectively.

[0160] Step S032: According to the arrangement sequence of the sub-regions, first tighten the bolts of the first sub-region, then tighten the bolts of the second sub-region. When tightening the bolts of the first sub-region, tighten the bolts in the order of the screw hole A numbers from small to large. When tightening the bolts of the second sub-region, tighten the bolts in the order of the screw hole A numbers from small to large.

[0161] The above step S032 specifically includes: performing multiple tightening steps, and each time the above tightening step is performed, the tightening torque increases by a preset torque value until the tightening torque reaches a threshold M.

[0162] The above step S032 specifically includes:

[0163] Step S0321: Perform the first tightening step;

[0164] In this step, the specific process can be as follows: Following the sequence of the sub-regions and the numbering of the screw holes A within each sub-region, tighten the bolts on the two straight sides S1 in the first sub-region at least once, increasing the tightening torque by a preset torque value (e.g., 5 N*m) with each turn, until the tightening torque on all bolts on the straight sides S1 reaches a first torque value M1 (e.g., 30 N*m). Then, apply a pre-tightening torque to the bolts on the corner side S2, which is less than the first torque value M1 (the application of the pre-tightening torque can be achieved by the operator slightly tightening the bolts by hand). In one embodiment, the bolts on all straight sides S1 can be tightened 3-4 turns until the tightening torque reaches 30 N*m, and then the bolts on the corner side S2 can be manually tightened.

[0165] Step S0322: Perform the second tightening step;

[0166] In this step, according to the arrangement sequence of the sub-regions and the screw hole A numbering sequence in each sub-region, the bolts on the two straight sides S1 in the first sub-region are tightened at least once, and the tightening torque increases by a preset torque value (for example, the preset torque value can be 5 N*m) for each turn of the bolts, until the tightening torque on all bolts on the straight sides S1 reaches the second torque value M2 (for example, the second torque value M2 is 30 N*m); then, tightening torque is applied to all bolts until the tightening torque reaches the threshold M (for example, the threshold M is 35 N*m). In one embodiment, in this step, the bolts on the two straight sides S1 can be tightened first until the tightening torque reaches 30 N*m, and then the bolts on the corner side S2 of the second sub-region are tightened for the last turn. The bolts on the corner side S2 of the second sub-region can also be tightened at least once, and the tightening torque increases by the preset torque value for each turn of tightening, until the tightening torque on all bolts reaches the threshold M.

[0167] It should be noted that in step 032 above, during the bolt tightening process, the size of the gap between the sealing surface 10A of the flange 10 and the sealing surface 10A of the part to be sealed can be observed with the naked eye to determine whether the sealing ring is subjected to uniform force diagonally.

[0168] It should also be noted that in step S032 above, before performing multiple tightening steps, the flange 10 can be pre-pressurized. The specific process is as follows: the operator can first tighten the bolts by hand, roughly flatten the sealing ring, and then use a wrench to lightly tighten all the bolts once.

[0169] It should also be noted that in some other embodiments, when tightening the bolts on the straight side S1, the bolts can be tightened sequentially according to the bolt hole A number in the first pass, and in the second pass, the bolts can be tightened on one side first in ascending order of the numbers, and then the other side can be tightened.

[0170] Furthermore, after step S03 above, the runway flange sealing method may also include:

[0171] Step S04: When the tightening torque is at the threshold value, a preliminary leak check can be performed. If there is no leak, it indicates that the seal is good. If a single-point leak is detected, apply force to the leak point until it is sealed. During this process, the screws in other positions remain stationary. However, if the third threshold value M3 is applied to the bolt at the leak point, the tightness of the screws around the leak point must be checked and tightened appropriately. If there are multiple leaks, repeat the tightening steps multiple times. For each additional tightening step, the tightening torque increases by the preset torque value until a single-point leak or no leak at all is gradually achieved.

[0172] Example 3

[0173] Please see Figure 5 As shown, the flange 10 is a rectangular flange, and the sealing surface 10A of the flange 10 includes four straight sides S1 and four corner sides S2. The four straight sides S1 are respectively the first straight side S11 and the second straight side S12, and the third straight side S13 and the fourth straight side S14, which are opposite each other. The four corner sides S2 are respectively the first corner side S21 and the second corner side S22, which are located along one diagonal of the sealing surface 10A, and the third corner side S23 and the fourth corner side S24, which are located along the other diagonal of the sealing surface 10A.

[0174] The flange sealing method provided in this disclosure, when applied to a rectangular flange, may include the following steps:

[0175] Step S01: Based on the shape and distribution of the multiple sides of the rectangular flange, divide the sealing surface 10A of the rectangular flange into 4 sub-regions;

[0176] In this step, the third straight side S13 and the fourth straight side S14 are divided into the first sub-region, the first straight side S11 and the second straight side S12 are divided into the second sub-region, the first corner side S21 and the second corner side S22 are divided into the third sub-region, and the third corner side S23 and the fourth corner side S24 are divided into the fourth sub-region.

[0177] Step S02: Sort the multiple sub-regions;

[0178] In this step, the longest length of the diagonal side is greater than the longest length of the parallel side, and the lengths of the two sets of diagonals are approximately the same. Therefore, the sorting number of the first sub-region is 1, the sorting number of the second sub-region is 2, the sorting number of the third sub-region is 3, and the sorting number of the fourth sub-region is 4.

[0179] Step S03: Apply tightening torque to the bolts in each sub-region in ascending order of their sorting numbers. When applying tightening torque to the bolts in any sub-region, apply tightening force to each bolt in that sub-region in ascending order of their bolt hole numbers.

[0180] Step S03 specifically includes:

[0181] Step S031: Number the screw holes A in each sub-region. The numbering results for screw holes A are as follows:

[0182] For the first sub-region, both sides are of equal length, and each side has 7 screw holes A. Therefore, according to the screw hole A numbering rules, the screw holes A on one side are numbered 11, 7, 3, 1, 4, 8, 12, and the screw holes A on the other side are numbered 13, 9, 5, 2, 6, 10, 14. (The second paragraph is a repetition of the first sentence and can be omitted.) 7, 3, 1, 4, 8, 12, and the screw holes A on the other side are numbered 13, 9, 5, 2, 6, 10, 14 respectively; For the third sub-region, the lengths of each side in the two corner sides S2 are equal, and there are 4 screw holes A distributed, with one side numbered 5, 1, 2, 6 and the other side numbered 7, 3, 4, 8; For the fourth sub-region, the lengths of each side in the two corner sides S2 are equal, and there are 4 screw holes A distributed, with one side numbered 5, 1, 2, 6 and the other side numbered 7, 3, 4, 8.

[0183] Step S032: Tighten the bolts of each sub-region in the order of sub-region number from 1 to 4, and tighten the bolts in the order of the above-mentioned screw hole A number from small to large when tightening each sub-region.

[0184] The above step S032 specifically includes: performing multiple tightening steps, and each time the above tightening step is performed, the tightening force increases by a preset torque value until the tightening torque reaches a threshold M.

[0185] The above step S032 specifically includes:

[0186] Step S0321: Perform the first tightening step;

[0187] In this step, the specific process can be as follows: Following the arrangement sequence of the sub-regions and the screw hole A numbering sequence within each sub-region, tighten all bolts on the straight side S1 at least once, increasing the tightening torque by a preset torque value (e.g., 5 N*m) for each turn, until the tightening torque on all bolts on the straight side S1 reaches a first torque value M1 (e.g., 30 N*m). Then, apply a pre-tightening torque to the bolts on the corner side S2, which is less than the first torque value M1 (the application of pre-tightening torque can be achieved by the operator slightly tightening the bolts by hand). In one embodiment, all bolts on the straight side S1 can be tightened 3-4 turns until the tightening torque reaches 30 N*m, then the bolts on the corner side S2 can be manually tightened.

[0188] Step S0322: Perform the above tightening steps a second time;

[0189] In this step, following the sequence of the sub-regions and the numbering of the screw holes A within each sub-region, all bolts on the straight side S1 are tightened at least once. For each turn of the bolts on the straight side S1, the tightening torque increases by a preset torque value (e.g., the preset torque value could be 5 N*m), until the tightening torque on all bolts on the straight side S1 reaches a second torque value M2 (e.g., the first torque value M2 is 60 N*m). Then, tightening torque is applied to all bolts until the tightening torque reaches a threshold M, for example, the threshold M is 80 N*m. In one embodiment, in this step, after tightening all bolts on the straight side S1 for several turns, the bolts on the corner side S2 are tightened for the last 1-2 turns until the tightening torque on the corner side S2 reaches the threshold M.

[0190] It should be noted that during the above steps, the size of the gap between the sealing surface 10A of the flange 10 and the sealing surface 10A of the part to be sealed can be observed with the naked eye to determine whether the sealing ring is subjected to uniform force diagonally.

[0191] It should also be noted that in step S032 above, before performing multiple tightening steps, the flange 10 can be pre-pressurized. The specific process is as follows: the operator can first tighten the bolts by hand, roughly flatten the sealing ring, and then use a wrench to lightly tighten all the bolts once.

[0192] Furthermore, after step S03 above, the rectangular flange sealing method may also include:

[0193] Step S04: When the tightening torque is at the threshold value, a preliminary leak check can be performed. If there is no leak, it indicates that the seal is good. If a single-point leak is detected, apply force to the leak point until it is sealed. During this process, the screws in other positions remain stationary. However, if the third threshold value M3 is applied to the bolt at the leak point, the tightness of the screws around the leak point must be checked and tightened appropriately. If there are multiple leaks, repeat the tightening steps multiple times. For each additional tightening step, the tightening torque increases by the preset torque value until a single-point leak or no leak at all is gradually achieved.

[0194] The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, and are not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein. The scope of this disclosure is defined by the appended claims.

Claims

1. A method of sealing a flange having a sealing surface comprising a plurality of sides, the plurality of sides comprising straight sides and corner sides connecting between two adjacent straight sides, each side having a bolt hole for receiving a bolt; characterized in that, The method comprises: dividing the sealing surface into a plurality of sub-regions, wherein the straight side edge and the corner side edge are divided into different sub-regions; sorting the plurality of sub-regions, wherein the sorting rule of the plurality of sub-regions is configured to: the serial number of the sub-region corresponding to the straight side edge is smaller than the serial number of the sub-region corresponding to the corner side edge; the sorting rule of the plurality of sub-regions is configured to: among at least two sub-regions corresponding to the straight side edge, the longer the longest length of the straight side edge is, the smaller the serial number of the sub-region is; and / or, among at least two sub-regions corresponding to the corner side edge, the longer the longest length of the corner side edge is, the smaller the serial number of the sub-region is; applying a tightening torque to the bolts of each sub-region in turn according to the sorting serial number of the plurality of sub-regions from small to large; when the tightening torque is applied to the bolt of any sub-region, the tightening torque is sequentially applied to the bolts in the sub-region according to the hole number from small to large, wherein the hole number rule of any sub-region is configured to: each side edge is numbered from the center position to the two side positions, and the holes are numbered from small to large, and the holes are staggered between different side edges, and the numbers of the two holes on any side edge about the center position of the side edge are adjacent; the hole number rule of any sub-region is further configured to: when the number of holes on any side edge is odd, there is a center hole at the center position of the side edge, and the number of the center hole on the side edge is the smallest; when the number of holes on any side edge is even, there are two center holes at the center position of the side edge, and the numbers of the two center holes on the side edge are the smallest and adjacent.

2. The method of flange sealing of claim 1, wherein, The sealing surface is divided into a plurality of sub-regions, specifically including: taking two straight side edges of the plurality of side edges as a pair of opposite edges, taking two corner side edges arranged along the diagonal of the sealing surface as a pair of opposite corners, each pair of opposite edges corresponds to a sub-region, and each pair of opposite corners corresponds to a sub-region.

3. The method of flange sealing of claim 1, wherein, In any sub-region, one of the two side edges is referred to as the first side edge, and the other is referred to as the second side edge; the hole number rule of any sub-region is specifically configured to: when the number of holes on the first side edge and the second side edge is odd, the number of the center hole at the center position on the first side edge is 1, and the number of the center hole at the center position on the second side edge is 2; on the first side edge, taking the center hole numbered 1 as the center of symmetry, the numbers of the two holes symmetric about the center of symmetry and spaced n hole spacings away from the center hole numbered 1 are N and (N+1) respectively; on the second side edge, taking the center hole numbered 2 as the center of symmetry, the numbers of the two holes symmetric about the center of symmetry and spaced n hole spacings away from the center hole numbered 2 are (N+2) and (N+3) respectively; wherein N=4n-1, and n is an integer greater than or equal to 1.

4. The method of flange sealing of claim 1, wherein, In any sub-region, one of the two side edges is referred to as the first side edge, and the other is referred to as the second side edge; the hole number rule of any sub-region is specifically configured to: When the number of screw holes on the first side edge and the second side edge is even, the two center screw holes on the first side edge are numbered 1 and 2 respectively, and the two center screw holes on the second side edge are numbered 3 and 4 respectively; On the first side edge, the midpoint between the center screw hole numbered 1 and the center screw hole numbered 2 is taken as the center of symmetry, and the two screw holes symmetric about the center of symmetry are numbered N and (N+1) respectively, where N is the number of screw holes away from the screw hole numbered 1, and (N+1) is the number of screw holes away from the screw hole numbered 2; On the second side edge, the midpoint between the center screw hole numbered 3 and the center screw hole numbered 4 is taken as the center of symmetry, and the two screw holes symmetric about the center of symmetry are numbered (N+2) and (N+3) respectively, where (N+2) is the number of screw holes away from the screw hole numbered 3, and (N+3) is the number of screw holes away from the screw hole numbered 4; Wherein, N=4n+1, n is an integer greater than or equal to 1.

5. The method of flange sealing of claim 1, wherein, One of the two side edges in any sub-region is taken as the first side edge, and the other is taken as the second side edge; the screw hole numbering rule of any sub-region is specifically configured as: When the number of screw holes on the first side edge is odd and the number of screw holes on the second side edge is even, the center screw hole on the first side edge is numbered 1, and the two center screw holes on the second side edge are numbered 2 and 3 respectively; On the first side edge, the center screw hole numbered 1 is taken as the center of symmetry, and the two screw holes symmetric about the center of symmetry and away from the screw hole numbered 1 by n hole distances are numbered N and (N+1) respectively; On the second side edge, the midpoint between the screw hole numbered 2 and the screw hole numbered 3 is taken as the center of symmetry, and the two screw holes symmetric about the center of symmetry are numbered (N+2) and (N+3) respectively, where (N+2) is the number of screw holes away from the screw hole numbered 2, and (N+3) is the number of screw holes away from the screw hole numbered 3; Wherein, N=4n, n is an integer greater than or equal to 1.

6. The method of flange sealing of claim 1, wherein, One of the two side edges in any sub-region is taken as the first side edge, and the other is taken as the second side edge; the screw hole numbering rule of any sub-region is specifically configured as: When the number of screw holes on the first side edge is even and the number of screw holes on the second side edge is odd, The two center screw holes on the first side edge are numbered 1 and 2 respectively, and the center screw hole on the second side edge is numbered 3; On the first side edge, the midpoint between the center screw hole numbered 1 and the center screw hole numbered 2 is taken as the center of symmetry, and the two screw holes symmetric about the center of symmetry are numbered N and (N+1) respectively, where N is the number of screw holes away from the screw hole numbered 1, and (N+1) is the number of screw holes away from the screw hole numbered 2; On the second side edge, taking the screw hole numbered 3 as a center of symmetry, in two screw holes symmetric about the center of symmetry and spaced n hole distances from the screw hole numbered 3, the number of one screw hole is recorded as (N+2), and the number of the other screw hole is recorded as (N+3); Wherein, N=4n, n is an integer greater than or equal to 1.

7. The method of sealing a flange according to any one of claims 1 to 6, wherein The method further comprises: The process of tightening all the bolts on the side edges at least once in the order of the sorting sequence number of the plurality of sub-regions from small to large is recorded as a tightening step, and the tightening step is executed at least twice, and each time the tightening step is executed, the tightening torque increases by a preset torque value until the tightening torque reaches a threshold value.

8. The method of sealing a flange of claim 7, wherein, The method further comprises: When the i1th tightening step is executed, all the bolts on the straight side edges are tightened at least once in the order of the sorting sequence number of the plurality of sub-regions from small to large, and each time the bolts are tightened, the tightening torque increases by a preset torque value, until the tightening torque reaches a first torque value, and a pre-tightening torque is applied to all the bolts on the corner side edges, wherein the pre-tightening torque is less than the first torque value, and i1 is an integer greater than or equal to 1.

9. The method of sealing a flange of claim 8, wherein, The method further comprises: When the i2th tightening step is executed, all the bolts on the straight side edges are tightened at least once in the order of the sorting sequence number of the plurality of sub-regions from small to large, and each time the bolts are tightened, the tightening torque increases by a preset torque value, until the tightening torque reaches a second torque value from the first torque value, and all the bolts on the side edges are tightened at least once in the order of the sorting sequence number of the plurality of sub-regions from small to large, and each time the bolts are tightened, the tightening torque increases by a preset torque value, until the tightening torque of all the bolts reaches the threshold value, and i2 is an integer greater than i1.

10. The method of sealing a flange of claim 7, wherein, After the tightening torque is applied to the bolts of each sub-region in the order of the sorting sequence number of the plurality of sub-regions from small to large, the method further comprises: When the tightening torque reaches the threshold value, a gas leakage detection step is executed to determine the number and position of the gas leakage points; When the number of gas leakage points is 1, a tightening torque is applied to the bolts at the position corresponding to the gas leakage point, and if the tightening torque is greater than or equal to a third threshold value, a tightening torque is applied to the bolts at a position adjacent to the gas leakage point; When the number of gas leakage points is greater than 1, the above tightening step and the above gas leakage detection step are repeatedly executed until the number of gas leakage points is less than or equal to 1.

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