Method, system and program for managing gaskets

Abstract

The present invention has an inner cut (4) in a non-restrained part (2-2) that is adjacent to a restrained part (2-1) that is restrained between flanges (16-1, 16-2), and the shape of the inner cut changes as a result of the load applied to the restrained part. Minimum information can be obtained from the change in shape of the inner cut. Thus, the change in shape of a gasket that is subjected to a load between flanges is observed directly, and the results of the observation are used in the management of the fastening of the gasket, improving the gasket and the management thereof.

Description

[Technical field]

[0001] The present disclosure relates to a gasket used, for example, for fastening a piping system. T Concerning management techniques. [Background technology]

[0002] The tightening torque and bolt axial force applied to the flange by the bolts are traditionally used for the tightening management of gaskets. The tightening torque and bolt axial force are tightening information related to the bolts that tighten the flanges. Regarding the tightening of this gasket, a system is known that uses tightening surface pressure corresponding to the type of gasket and internal fluid, multiple tightening forces, bolt-related information, etc., to grasp the tightening torque (for example, Patent Document 1). Regarding the tightening of a bolt, it is known to convert the strain generated in the bolt into data and visualize the tightening state of the bolt (for example, Patent Document 2). Also known is a system that uses a sheet-type pressure sensor embedded inside the gasket to measure the force applied to a part of the gasket by tightening (for example, Patent Document 3). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-225219 A [Patent Document 2] JP 2015-141345 A [Patent Document 3] Patent No. 4699935 Summary of the Invention [Problem to be solved by the invention]

[0004] The reason that bolt tightening torque and axial force values ​​are used in managing gasket tightening is that bolts are the means for tightening flanges, and the tightening force from the bolts can be easily determined by measuring the bolt strain.

[0005] However, after examining the relationship between the bolts, flanges, and gaskets, it was found that the bolt tightening force acts on the flange, and only indirectly acts on the gasket through the flange. In other words, the flange receives the load caused by the bolt tightening, and this load only acts on the gasket through the flange. The torque value and axial force applied to the bolt are loads acting on a part of the flange, and cannot be said to represent the surface pressure acting on the gasket.

[0006] For this reason, the following problems arise in managing the tightening of the gasket:

[0007] a) The torque and axial force values ​​obtained from the bolts are information about the bolts, and cannot be said to measure the surface pressure received by the gasket.

[0008] b) In terms of the surface pressure that the gasket receives from the flange, the bolt torque value and axial force value are only indirect information and serve only as a guide to the surface pressure.

[0009] c) The bolt torque and axial force values ​​are affected by the tightening condition of the bolts and flanges, and this tendency to fluctuate cannot be ignored.

[0010] When gasket surface pressure is estimated using torque values ​​or axial force values ​​measured with a torque wrench or bolt axial force meter, if the tightening condition of the bolts or flanges is affected, the relationship between the surface pressure applied to the gasket (= estimated surface pressure) and the surface pressure actually received by the gasket (= actual surface pressure) is as follows: Estimated surface pressure ≠ actual surface pressure Even if the measurement accuracy of the torque and axial force values ​​is improved, the estimated contact pressure and the actual contact pressure of the gasket do not match. It is not possible to grasp the contact pressure that the gasket receives.

[0011] Regarding this problem, the inventors have found that the change in shape of the gasket depends on the load applied between the flanges, and that observing the change in shape is useful for managing the fastening of the gasket. Patent Documents 1 to 3 do not disclose or suggest this problem. Furthermore, the configurations disclosed in Patent Documents 1 to 3 cannot solve this problem.

[0012] Therefore, based on the above problems and findings, the object of the present disclosure is to directly observe the shape change of a gasket that is subjected to a load between flanges, and to use the observation results in managing the fastening of the gasket. T The aim is to improve management techniques. [Means for solving the problem]

[0015] In order to achieve the above object, according to one aspect of the management method of the present disclosure, Supported by the restraint section that is restrained between the flanges load By Shape changes The long side extends along the periphery of the non-constrained portion adjacent to the constrained portion. Equipped with an inner cut Using a gasket, Installing a gasket; The above The method includes a step of applying a load between the flanges to the gasket that is restrained between the flanges, and a step of measuring a shape of the inner cut that has changed due to the load, Inner cut shape change The tightening between the flanges is controlled based on the above.

[0016] In this management method, the gasket may further be used such that opposing surfaces constituting the long side of the inner cut come into contact with each other due to a change in shape of the inner cut caused by the load. This management method may further include a step of acquiring minimum point information from a change in shape of the inner cut.

[0017] In order to achieve the above object, according to one aspect of a management system of the present disclosure, Load is applied between the flanges On the periphery of the gasket The long side extends along A measuring means for measuring the shape of the inner cut; Inner cut shape change The present invention includes a management server that generates management information for managing the fastening of the gasket based on the information, and an information presentation unit that presents the management information.

[0018] In order to achieve the above object, according to one aspect of the program of the present disclosure, ,centre A gasket that is restrained between flanges and receives a load On the fringes To The long side extends along A function for acquiring shape information of an inner cut, a function for generating management information for managing fastening of the gasket based on the shape information, and a function for presenting the management information. W This is realized by a computer.

[0019] In this program, The inner cut is such that the opposing surfaces constituting the long side come into contact with each other due to a change in shape of the inner cut caused by the load, Furthermore, the computer realizes a function of acquiring minimum point information from the shape change of the inner cut. Effect of the Invention

[0020] According to the present invention, any one of the following effects can be obtained.

[0021] (1) The load that the gasket receives from between the flanges causes strain in the gasket, which can be manifested as a change in the shape of the inner cut of the gasket. The change in the shape of the inner cut can be visualized and easily recognized.

[0022] (2) By observing the change in shape of the inner cut, the load applied to the gasket can be easily determined without being affected by the tightening state of the bolts, and the tightening management of the gasket can be properly performed.

[0023] (3) The load applied to the gasket is estimated from the shape change of the inner cut. The estimated load is equivalent to the actual surface pressure of the gasket received from the flange. Therefore, this method can improve the accuracy of gasket management, such as fastening management and gasket life prediction.

[0024] (4) The shape change of the inner cut and the load estimated from this shape change directly reflect the tightening state of the gasket, unlike the torque value or axial force value of the bolt. Therefore, by observing such shape changes and estimating the load, the accuracy of gasket management can be improved regardless of the skill of the worker.

[0025] Other objects, features, and advantages of the technology of the present disclosure will become more apparent with reference to the accompanying drawings and each embodiment. [Brief description of the drawings]

[0026] [Figure 1] FIG. 2A is a plan view showing a gasket according to a first embodiment, and FIG. 2B is an enlarged perspective view showing a portion IB of FIG. [Diagram 2] FIG. 2 is a diagram showing a flange fastening portion according to the first embodiment. [Diagram 3] 3 is a diagram showing a cross-sectional end surface taken along line III-III in FIG. 2. [Figure 4] FIG. 1A is an enlarged view of the inner cut, and FIG. 1B is a view showing changes in the shape of the inner cut. [Diagram 5] 1A, 1B and 1C are diagrams showing modified inner cuts. [Figure 6] FIG. 1 is a diagram showing a gasket management system according to a first embodiment. [Figure 7] FIG. 13 is a diagram showing a gasket management database. [Figure 8] FIG. 1A is a diagram showing a comparative example, and FIG. [Figure 9] FIG. 13 is a diagram showing the relationship between the shape change and the load in Examples 1, 2, 3, and 4. [Figure 10] FIG. 13 is a diagram showing the relationship between minimum points appearing in shape change and load. [Figure 11] FIG. 1 is a diagram showing the relationship between the load and the inflection points (without minimum points) that appear in the shape change. [Figure 12] FIG. 10A is a diagram showing the shape of a gasket according to Example 5, FIG. 10B is a diagram showing an example of the state before a load is applied, and FIG. 10C is a diagram showing an example of the state when a load of a predetermined value is applied. [Figure 13] FIG. 13 is a diagram showing an example of shape observation according to the fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] First Embodiment A in Fig. 1 shows a gasket 2 according to a first embodiment. The configuration shown in Fig. 1 is an example, and the present disclosure is not limited to such a configuration. In Fig. 1, an X-axis, a Y-axis, and a Z-axis are also shown as an example.

[0028] The gasket 2 is, for example, a sheet gasket made of a material that is a mixture of polytetrafluoroethylene tetrafluoroethylene resin (PTFE) and a filler. The gasket 2 may be made of a resin material other than PTFE or a rubber material. In addition, the gasket 2 may be made of a metal material, or a combination of a metal material with ceramic, a heat-resistant fiber material, or other materials. Furthermore, the gasket 2 may be a spiral gasket 70 (FIG. 12), a flat gasket with a sheet of PTFE or graphite attached to the surface, a cam profile gasket with a groove formed on the surface of the gasket or a flange on the outer edge, etc.

[0029] A constrained portion 2-1 is set on the inner diameter side, and a non-constrained portion 2-2 is set on the outer diameter side of this gasket 2. The constrained portion 2-1 is an area that contacts between the flanges 16-1 and 16-2 (Figs. 2 and 3) and receives a load F from between the flanges 16-1 and 16-2. In contrast, the non-constrained portion 2-2 is an area that does not contact between the flanges 16-1 and 16-2.

[0030] Inner cuts 4-1, 4-2, 4-3, and 4-4 (hereinafter, simply referred to as inner cuts 4 when no specific position is specified) are formed in the non-constrained portion 2-2. Each inner cut 4 is a through hole portion that penetrates the front and back of the non-constrained portion 2-2 of the gasket 2, and is a means for facilitating detection of changes in the shape of the gasket 2. Therefore, each inner cut 4 constitutes a shape observation portion for observing changes in the shape of the gasket 2 when a load F is applied to the constrained portion 2-1.

[0031] <Inner cut 4> Fig. 1B shows an enlarged view of the inner cut 4 at part IB in Fig. 1A. This inner cut 4 is a through hole portion that penetrates the top and bottom surfaces of the gasket 2 with a constant arc-shaped long side length L and width W in the circumferential direction of the gasket 2. Each inner cut 4 has opposing vertical surface portions 6-1, 6-2 with a constant width W, and inner peripheral surface portions 8-1 and outer peripheral surface portions 8-2 that face each other with the long side length L. Height D is the thickness of the gasket 2 before deformation.

[0032] To detect changes in the shape of the gasket 2, each inner cut 4 may be set at multiple locations on the gasket 2. It is preferable that the setting locations are not biased in order to avoid the influence of elastic interactions from the flanges 16-1, 16-2 and to increase the accuracy of detecting changes in shape. In this embodiment, each inner cut 4 is set at four locations on the X-axis and Y-axis, making it possible to detect changes in shape over a wide range.

[0033] <Flange fastening part 12> 2 shows a cutaway view of a flange fastening portion 12 including a gasket 2. This flange fastening portion 12 is an example, and the present disclosure is not limited to the configuration shown in FIG.

[0034] The flange fastening portion 12 includes a flange 16-1 on the pipeline 14-1 side, a flange 16-2 on the pipeline 14-2 side (FIG. 3), a gasket 2, a plurality of bolts 18, and nuts 20.

[0035] The flange 16-1 is integrally formed with the end surface of the pipe 14-1, and similarly, the flange 16-2 is integrally formed with the end surface of the pipe 14-2. The flanges 16-1 and 16-2 have a larger diameter than the pipes 14-1 and 14-2, and a plurality of bolts 18 and nuts 20 are attached at predetermined angular intervals.

[0036] A gasket 2 is installed between the flanges 16-1, 16-2, inside the bolts 18 and nuts 20. The gasket 2 constitutes a sealing member for the flange fastening portion 12. Therefore, when the bolts 18 and nuts 20 are fastened, the gasket 2 receives a load F applied to the flanges 16-1, 16-2, and the pipelines 14-1, 14-2 are fastened and sealed.

[0037] The restrained portion 2-1 of the gasket 2 is sandwiched between the flanges 16-1, 16-2 and contacts and is restrained by the flanges 16-1, 16-2. The non-restrained portion 2-2 protrudes around the restrained portion 2-1 and does not contact the flanges 16-1, 16-2, i.e., is not restrained by the flanges 16-1, 16-2.

[0038] When the bolts 18 and nuts 20 are tightened, the restrained portion 2-1 receives a load F from the flanges 16-1 and 16-2, whereas the non-restrained portion 2-2 constitutes a free end that does not receive the load F.

[0039] When a load F acts on the restraint portion 2-1 from the flanges 16-1, 16-2, the load strain of the restraint portion 2-1 due to the load F spreads to the non-restraint portion 2-2 that is integral with the restraint portion 2-1, causing a shape change in the inner cut 4. As a result, each inner cut 4 of the non-restraint portion 2-2 constitutes a site for detecting a shape change appearing in the gasket 2. If the load F acts in the Z-axis direction, strain occurs, for example, in the X-axis and Y-axis directions.

[0040] <Relationship between the restrained portion 2-1, the non-restrained portion 2-2, and the flanges 16-1 and 16-2> Fig. 3 shows a cross-sectional end surface taken along line III-III in Fig. 2. The restrained portion 2-1 of the gasket 2 is sandwiched and restrained between the gasket seats 22 of the flanges 16-1 and 16-2. In contrast, the non-restrained portion 2-2 protrudes into the gap 24 between the flanges 16-1 and 16-2. The non-restrained portion 2-2 is integral with the restrained portion 2-1, is supported between the flanges 16-1 and 16-2, and is a free end that protrudes into the gap 24. In other words, the non-restrained portion 2-2 is in a cantilever state.

[0041] Strain and deformation that occur in the restrained portion 2-1 when the load F is applied from the flanges 16-1, 16-2 appear as a change in shape in the non-restrained portion 2-2. This change in shape can be easily observed from the inner cut 4. In other words, the change in shape of the gasket 2 that appears in the non-restrained portion 2-2 is strain or deformation caused by being pushed out from between the gasket seats 22, and represents the load that the restrained portion 2-1 of the gasket 2 receives from the flanges 16-1, 16-2.

[0042] <Observation of shape change of inner cut 4> The inner cut 4 is formed in order to make the strain occurring in the unconstrained portion 2-2 apparent as a significant change in shape and to facilitate its observation.

[0043] A in Figure 4 shows the original shape of the inner cut 4. If the X axis is taken in the tangential direction of the gasket 2, the Y axis is taken at the center of the inner cut 4, and the Z axis is taken in the direction in which the load F is applied, when the load F is applied to the restraint portion 2-1 from the flanges 16-1 and 16-2, a shape change (= strain) occurs in the spacing direction between the flanges 16-1 and 16-2 and in the direction intersecting this spacing direction. This shape change includes a shape change in the circumferential direction of the gasket 2.

[0044] As shown in FIG. 4B, the non-constrained portion 2-2 expands by ΔY in the radial direction (indicated by arrow a) of the gasket 2, and the inner peripheral surface portion 8-1, the outer peripheral surface portion 8-2, and the vertical surface portions 6-1 and 6-2 also move in the radial direction of the gasket 2. At the same time, the width W of the inner cut 4 is narrowed to a width ΔW, as shown by the spacing distance between the inner peripheral surface portion 8-1 and the outer peripheral surface portion 8-2, as indicated by arrows b and c. These are shape changes of the gasket 2 that represent the load F applied to the constrained portion 2-1, that is, the load that the gasket 2 is receiving. In this example, the shape changes in the XY axis directions are illustrated, but it goes without saying that shape changes in the Z axis direction and thickness direction also appear in the shape of the inner cut 4.

[0045] Therefore, the strain generated in the restraining portion 2-1 and the unrestrained portion 2-2 due to the load F received from the flanges 16-1 and 16-2 can be manifested as a shape change of the inner cut 4, making its observation easier.

[0046] <Modification example of the inner cut 4> The inner cut 4 is not limited to the form shown in B of FIG. 1. A, B, and C in FIG. 5 show modification examples of the inner cut 4. In FIG. 5, the parts corresponding to B in FIG. 1 are marked with the same reference numerals.

[0047] As shown in FIG. 5A, the inner cut 4 may be formed on parallel or non-parallel planes composed of linear opposing faces 9-1 and 9-2 instead of the aforementioned inner peripheral face 8-1 and outer peripheral face 8-2. Or, as shown in FIG. 5B, it may be formed in a square or fan shape composed of four faces, namely opposing faces 7-1, 7-2, and opposing faces 9-1, 9-2. Also, as shown in FIG. 5C, by forming faces 9-11 and 9-12 on the opposing face 9-1, the space between the opposing faces 9-1 and 9-2 may be formed with different widths, for example, Wa and Wb (Wa < Wb). Even in such a form, the shape change generated in the unrestrained portion 2-2 due to the load F received by the restraining portion 2-1 can be easily detected from the inner cut 4.

[0048] Note that a sensor member such as metal or resin may be installed in the space portion of the inner cut 4, and the shape change of the inner cut 4 may be extracted from this sensor member.

[0049] <Management process of the gasket 2> The management process of the gasket 2 is an example of the management method of the present disclosure. This management process includes a generation process S1 of the restraining portion 2-1 and the unrestrained portion 2-2, a load F application process S2, a shape information acquisition process S3, and a presentation process S4 of shape information and the like. S1 to S4 attached to each process illustrate the order of each process, and the terms cited are only used for convenience.

[0050] Step S1 of generating the constrained portion 2-1 and the non-constrained portion 2-2: When the gasket 2 is placed between the flanges 16-1 and 16-2, the portion of the gasket 2 that contacts the flanges 16-1 and 16-2 becomes the constrained portion 2-1, and the portion of the gasket 2 that does not contact the flanges 16-1 and 16-2 becomes the non-constrained portion 2-2. In other words, the constrained portion 2-1 and the non-constrained portion 2-2 of the gasket 2 are generated by being placed between the flanges 16-1 and 16-2.

[0051] Load F application process S2: A load F is applied to the restrained portion 2-1 of the gasket 2, which is restrained by the flanges 16-1 and 16-2, by tightening the flanges 16-1 and 16-2. In response to this load F, the restrained portion 2-1 of the gasket 2 is distorted, and the shape of the non-restrained portion 2-2 is changed.

[0052] Shape information acquisition step S3: Regarding the shape change appearing in the non-constrained portion 2-2, the management server 30 (FIG. 6) receives the detection output of the strain sensor 28 and acquires shape information of the inner cut 4.

[0053] Presentation step S4 of shape information, etc.: The management server 30 generates presentation information including the shape information, and presents it by the information presentation unit 32 (FIG. 6).

[0054] Note that the shape information acquired in the shape information acquisition step S3 may be subjected to N-th order differentiation (multiple-stage differentiation) to highlight the change points of the shape information. If the result of this processing is reflected in the presented information in the presentation step S4, the change points of the shape information can be clarified.

[0055] <Gasket Management System 26> Fig. 6 shows a gasket management system 26 for executing the management process by information processing. The configuration shown in Fig. 6 is an example, and the present disclosure is not limited to such a configuration. In Fig. 6, the same parts as in Fig. 3 are given the same reference numerals.

[0056] The gasket management system 26 includes a strain sensor 28 , a management server 30 , and an information presentation unit 32 .

[0057] The strain sensor 28 measures the shape change appearing in the inner cut 4 of the gasket 2 and outputs a detection signal representing this shape change. This strain sensor 28 is an example of a means for detecting a shape change and converting it into an electrical signal. In addition to the strain sensor 28, a laser displacement meter, a camera, etc. may be used as a shape change observation means. The laser displacement meter shines a laser light on the inner cut 4, detects the shape change of the inner cut 4 by the reflected light, and observes the amount of change. The camera captures an image of the inner cut 4, and the management server 30 detects the strain appearing in the inner cut 4 by the number of pixels and obtains shape information according to the strain.

[0058] The management server 30 is composed of a computer with a communication function. This management server 30 has a processor 34, a memory unit 36, an input / output (I / O) unit 38, and a communication unit 40. The processor 34 executes the OS (Operating System) and management programs in the memory unit 36, and performs information processing for gasket management. The memory unit 36 ​​includes a storage medium for storing the OS and management programs. A gasket management database (DB) 42 (FIG. 7) is stored in this memory unit 36. Under the control of the processor 34, the communication unit 40 cooperates with a management terminal (not shown) to input and present information. The management terminal is also used for obtaining shape information and writing and reading to and from the gasket management DB 42.

[0059] Further, the information presenting unit 32 presents shape information and judgment information including the load under the control of the management server 30 .

[0060] <Information processing of management server 30> The information processing of the management server 30 includes the following steps: a) Acquisition and processing of the detection output of the strain sensor 28 b) Acquisition of shape information of inner cut 4 c) Generation of presentation information including shape information d) Presentation of estimated information by the information presentation unit 32 This includes processes such as:

[0061] <Gasket Management DB42> 7 shows an example of the gasket management DB 42. This gasket management DB 42 is used for processing such as estimating a load from shape information. In this gasket management DB 42, a gasket management file 44 is stored.

[0062] In this gasket management file 44, a gasket information section 46, an inner cut information section 47, a time information section 48, a load information section 50, a strain sensor information section 52, a detection information section 54, a judgment information section 56, and a history information section 58 are set. In the gasket information section 46, in addition to the identification information of the gasket 2, specification information for identifying the gasket 2 is stored.

[0063] The inner cut information section 47 stores shape information such as shapes representing the inner cuts 4-1, 4-2, 4-3, and 4-4, and their arrangement positions, sizes, and the like.

[0064] The time information section 48 stores time information such as the measurement date and time.

[0065] The load information section 50 stores load information that indicates the load F that is applied between the flanges 16-1, 16-2 by tightening the bolts 18.

[0066] The strain sensor information section 52 stores sensor information including the types and identification information of the strain sensors 28 (=28-1, 28-2, 28-3, 28-4) that detect the shapes.

[0067] The detection information section 54 stores shape detection values ​​obtained from each of the inner cuts 4 (=4-1, 4-2, 4-3, 4-4).

[0068] The determination information section 56 stores estimated load information that indicates the load estimated from the shape information by the information processing of the management server 30.

[0069] The history information section 58 stores history information such as acquisition of shape information and estimation processing.

[0070] <Advantages of the First Embodiment> According to the first embodiment, any one of the following effects can be obtained.

[0071] (1) Since the gasket 2 is provided with an inner cut 4, when the restraint portion 2-1 receives a load F from the flanges 16-1, 16-2, the strain generated in the restraint portion 2-1 can be visualized as a change in shape of the inner cut 4 of the non-restraint portion 2-2, and the change in shape corresponding to the load F can be easily observed from the inner cut 4.

[0072] (2) Shape information of the inner cut 4 is obtained from the detection output of each strain sensor 28 from the inner cut 4, and the load that the gasket 2 receives from the flanges 16-1, 16-2 can be estimated from the change in shape.

[0073] (3) The strain of the gasket 2 can be observed from the change in shape of the inner cut 4. The load received by the gasket 2 can be estimated from the change in shape without being affected by the tightening torque or axial force of the bolt 18, and the tightening state of the gasket 2 can be determined.

[0074] (4) The tightening condition of the gasket 2 is not affected by the skill of the worker, and the control accuracy can be improved.

[0075] Second Embodiment The method for managing a gasket 2 according to the second embodiment further includes an estimation step S5 using minimum point information in addition to the management method according to the first embodiment.

[0076] In the estimation process S5 using minimum point information, the shape information including the shape changes appearing in the inner cut 4 includes minimum points (Figure 10) for specific loads, and the management server 30 can estimate the tightening state of the gasket 2 from the minimum points, i.e., the load (= surface pressure) that the gasket 2 receives from the flanges 16-1, 16-2.

[0077] <Advantages of the second embodiment> According to the second embodiment, any one of the following effects can be obtained.

[0078] (1) The shape information can include local minimum points as singular information of the load.

[0079] (2) By associating this minimum point with the load to be set, the minimum point can be confirmed from the shape information and set to a specific load.

[0080] (3) The load F, i.e., the surface pressure, can be estimated from the change in shape of the inner cut 4 that the gasket 2 is subjected to, making it easy to monitor or adjust the tightening state of the gasket 2. EXAMPLES

[0081] An example of the gasket 2 of the present disclosure will be described together with a comparative example. <Comparative Example> 8A shows a gasket 2 according to a comparative example. In this comparative example, a restraining portion 2-1 and a non-restraining portion 2-2 are set concentrically with the same width or substantially the same width.

[0082] In the gasket 2 according to the comparative example, as shown in B of Fig. 8, shape observation portions 60-1, 60-2, 60-3, and 60-4 are set at positions corresponding to the inner cut 4 of the embodiment. The shape observation portions 60-1, 60-2, 60-3, and 60-4 are arranged at angular intervals of a central angle of 90 degrees in the non-constraint portion 2-2. The arrangement positions of the shape observation portions 60-1, 60-2, 60-3, and 60-4 are set at positions that do not overlap with the arrangement positions of the bolts 18.

[0083] <Example 1-4> Table 1 shows the shape of the inner cut 4 of the gasket 2 according to the embodiment, the measurement results, and the like.

[0084] [Table 1]

[0085] Table 1 shows the shapes of the inner cut 4, the long side distances at the completion of fastening, and the minimum point loads in Examples 1, 2, 3, and 4, as well as dimensional information and load information in comparative examples.

[0086] In Example 1, the long side length was 65 mm, the short side length (distance between long sides) was 1 mm, the circumference of the gasket 2 was 327 mm, the long side length / circumference was 0.20, the aspect ratio was 65, the long side distance at the completion of fastening was 0 mm, and the minimum point load was 145 kN.

[0087] In Example 2, when the long side length was 65 mm, the short side length (distance between long sides) was 3 mm, the circumference of the gasket 2 was 327 mm, the long side length / circumference was 0.20, and the aspect ratio was 22, the long side distance at the time of completion of fastening was 0 mm, and the minimum point load was 195 kN.

[0088] In Example 3, when the long side length was 16 mm, the short side length (distance between long sides) was 1 mm, the circumference of the gasket 2 was 327 mm, the long side length / circumference was 0.05, and the aspect ratio was 16, the long side distance at the time of completion of tightening was 0.6 mm, and the minimum point load was unidentifiable.

[0089] In Example 4, when the long side length was 16 mm, the short side length (distance between long sides) was 3 mm, the circumference of the gasket 2 was 327 mm, the long side length / circumference was 0.05, and the aspect ratio was 5, the long side distance at the time of completion of tightening was 2.6 mm and the minimum point load was unidentifiable.

[0090] In the comparative example, since the inner cut 4 does not exist, there is no corresponding data.

[0091] <Relationship between the long side distance of the inner cut and the load> FIG. 9 shows the relationship between the shape change (change in the long side distance) and the load in Examples 1, 2, 3 and 4.

[0092] Regarding the relationship between the change in the long side distance and the load, n1 indicates the change in Example 1, n2 indicates the change in Example 2, n3 indicates the change in Example 3, and n4 indicates the change in Example 4. Comparing these, it is clear that the shape changes of n1 and n2 are significant, and that the load applied to the gasket 2 can be easily identified by observing the shape changes.

[0093] <Minimum point information in shape change> In the case where the long side length L of the inner cut 4 is long, FIG. 10 shows the relationship between the load and the minimum point information appearing in the shape change, with the load on the horizontal axis and the strain on the vertical axis.

[0094] In FIG. 10, o1 indicates the shape change in the 0 (deg) direction, o2 indicates the shape change in the 45 (deg) direction, and o3 indicates the shape change in the 90 (deg) direction. Thus, in Examples 1 and 2, there is a minimum point in the shape change.

[0095] <Inflection point information in shape change> FIG. 11 shows the relationship between the load and the inflection points appearing in the shape change when the long side length L of the inner cut 4 is short.

[0096] In FIG. 11, p1 indicates the shape change in the 0 (deg) direction, p2 indicates the shape change in the 45 (deg) direction, and p3 indicates the shape change in the 90 (deg) direction. When the long side length L of the inner cut 4 is short, the inner circumferential surface portion 8-1 and the outer circumferential surface portion 8-2 of the inner cut 4 are not in contact with each other. Therefore, no minimum point occurs in the shape change. In other words, in Examples 3 and 4, only an inflection point is obtained in the circumferential strain in the 0 (deg) direction.

[0097] <Effects of the embodiment> As is clear from these examples, by measuring the change in shape of the inner cut 4, the relationship between the change in shape and the load can be identified.

[0098] In all of Examples 1 to 4, inflection point information or minimum point information can be obtained, but minimum point information can be obtained when the long side length L of the inner cut 4 is increased. Based on this minimum point information, the fastening state of the gasket 2, that is, the load (=surface pressure) that the gasket 2 receives from the flanges 16-1 and 16-2, can be estimated, and the fastening state of the flange fastening portion 12 can be judged.

[0099] Unlike torque management and bolt axial force measurement, such monitoring and measurement of shape changes measures the shape changes appearing in the inner cut 4 of the non-constrained portion 2-2 and makes it possible to obtain shape information representing the load from the gasket 2. Therefore, the load can be estimated from the shape change of the gasket 2 due to the load F applied to the flanges 16-1, 16-2 without being affected by the bolts 18 or the flanges 16-1, 16-2.

[0100] It was confirmed that the processed shape of the inner cut 4 can accommodate various diameters and thicknesses of the gasket 2 as well.

[0101] <Example 5> FIG. 12 shows an example of the configuration of a gasket 70 according to a fifth embodiment.

[0102] The gasket 70 is, for example, a laminate in which a plurality of members having different diameters are arranged coaxially, and is a spiral-wound gasket including an outer ring 701, a gasket body 702, and an inner ring 703. In the gasket 70, for example, only the inner ring 703, or the inner ring 703 and part or all of the gasket body 702, and part of the outer ring 701 are constrained portions 2-1 that abut against the gasket seat 22 (FIG. 3) and receive a load F. That is, in the gasket 70, part or all of the outer ring 701 serves as a non-constrained portion 2-2. In the gasket 70, the gasket body 702 deforms in response to the load F from the flanges 16-1 and 16-2, and the outer ring 701 is distorted in response to this deformation.

[0103] The gasket 70 has one or more inner cuts 4 formed in a part of the outer ring 701. The inner cuts 4 are, for example, at a predetermined distance t of 5 mm from the outer edge of the outer ring 701. In the fifth embodiment, for example, by observing a shape change Qa of the outer edge portion along the formation position of the inner cut 4, the shape of the inner cut 4 is measured and the surface pressure state of the gasket 70 is managed. The shape change Qa can be observed, for example, by using the strain sensor 28 of the gasket management system 26. The gasket management system 26 also calculates the shape of the inner cut 4 based on the measured shape change Qa. The management process of the fastening state of the gasket 70 can be performed in the same manner as in the above embodiment.

[0104] <About the composition of gasket 70> The outer ring 701 and the inner ring 703 are made of a metal material such as stainless steel, carbon steel, or titanium, and are formed into a ring of a predetermined thickness or a shape similar thereto. The gasket body 702 is formed by winding a laminate of a thin plate-like member made of a metal material, for example, and a buffer material (filler) such as graphite or fluororesin in a spiral shape between the inner wall surface of the outer ring 701 and the outer wall surface of the inner ring 703. The laminate constituting the gasket body 702 is formed, for example, into a "V" shaped cross section or a waveform similar thereto. The end faces of this laminate are fixed to the outer ring 701 and the inner ring 703 by spot welding, for example.

[0105] 12B, before a load F from the flanges 16-1 and 16-2 is applied to the gasket body 702, the inner cut 4a of the outer ring 701 is open to a predetermined width. When the load F acts through the gasket body 702, the outer ring 701 is opened to a predetermined width as shown in FIG. 2 As shown in FIG. 3C, a part or the whole of the opening portion is deformed to become a closed inner cut 4b.

[0106] 13, the horizontal axis represents load (kN) and the vertical axis represents strain (shape change), and shows the measurement values ​​of the circumferential shape change Qa (FIG. 12) appearing on the outer edge of the outer ring 701 measured by the strain sensor 28.

[0107] In the measurement results, when the load on the gasket increases, for example, there is no significant change from the start of loading until a certain value, and then when the load exceeds the certain value, a negative value is measured by the strain sensor. This indicates that a shape change has occurred, indicating that the outer edge of the outer ring 701 has been compressed in the circumferential direction. Then, the circumferential strain reaches a minimum point, for example, when the load is about 220 kN, and then increases in value in the positive direction.

[0108] <Effects of Example 5> (1) By measuring the change in shape of the outer ring 701 of the spiral-wound gasket 70 sandwiched between the flanges 16-1 and 16-2, the surface pressure of the gasket 70 due to the load F can be determined.

[0109] (2) When using a spiral-wound gasket 70, unlike torque management and bolt axial force measurement, monitoring and measurement of shape changes are performed by controlling the outer ring. 7 By measuring the shape change Qa that occurs in 01 and the shape change in inner cut 4, 70 Therefore, the load F applied to the flanges 16-1 and 16-2 can be estimated from the change in shape of the gasket 70 without being affected by the bolts 18 or the flanges 16-1 and 16-2.

[0110] <Additional Notes> Regarding the above-described embodiment and examples, the following supplementary notes are disclosed below.

[0111] (Appendix 1) A gasket installed between flanges of a flange fastening portion, a restraint portion that is restrained between the flanges and receives a load; A non-constrained portion that is not constrained between the flanges; A through hole portion provided in the non-restrained portion; wherein a change occurs in the through hole portion when the load is received.

[0112] (Appendix 2) A management system for managing a flange fastening part having a gasket between the flanges, a restraint portion that is restrained between the flanges and receives a load, a non-restraint portion that is not restrained between the flanges, and a through hole portion provided in the non-restraint portion, a gasket that changes the through hole portion when subjected to the load; a measuring device that measures a change in the through hole portion with or without contacting the gasket; a management server that acquires measurement information from the measuring instrument and generates management information including the fastening force between the flanges; an information presenting unit that presents the management information in association with the gasket or the flange fastening portion; A management system comprising:

[0113] (Appendix 3) A recording medium having a program for being realized by a computer recorded thereon, a function of acquiring shape information including a change caused in a through-hole portion in a non-restrained portion of the gasket by being restrained between flanges and receiving a load from the flanges; and a function of generating management information including a tightening force between the flanges based on the shape information; a function of presenting the management information; A recording medium on which a program for realizing the above on the computer is recorded.

[0114] Other Embodiments

[0115] (1) In the above embodiment and example, the initial fastening of the flange fastening portion 12 was described as being performed by observing the shape change that occurred in the gasket 2 when a load was applied between the flanges. However, this is not limited to the initial fastening of the flange fastening portion 12.

[0116] (2) The shape of the inner cut 4 described above is just one example, and the through-hole portion may be an arc shape that does not have a vertical surface portion 6, or a polygonal or rectangular shape with linear parallel or non-parallel surfaces.

[0117] (3) The above embodiment, comparative example, and example describe the load F applied to the gasket 2 sandwiched between the flanges 16-1 and 16-2, and the change in shape of the gasket 2. The load F applied to the gasket 2 is equivalent to the surface pressure that the gasket 2 receives from the flanges 16-1 and 16-2, and there is no qualitative difference between the two. In other words, from the relationship between the load F applied to the gasket 2 and the shape change appearing in the inner cut 4, it is possible to estimate the surface pressure of the gasket 2 from the shape change.

[0118] (4) In the process of managing the gasket 2, in the process of presenting shape information (S4), the management server 30 may generate presentation information by processing the acquired shape information such as multi-stage differentiation, and may present a display unit on the information presentation unit 32 (FIG. 6) that clearly indicates the change points.

[0119] As described above, the most preferred embodiment of the present disclosure has been described. The present disclosure is not limited to the above description. Various modifications and changes are possible for those skilled in the art based on the gist of the invention described in the claims or disclosed in the description for carrying out the invention. It goes without saying that such modifications and changes are included in the scope of the present disclosure. [Industrial Applicability]

[0120] The gasket of the present disclosure T The management method, system, and program make it possible to observe changes in the shape of the inner cut of a gasket that fastens flanges, and can therefore be used as management information for gasket tightening management and replacement without being affected by the tightening condition of the bolts or flanges. [Explanation of symbols]

[0121] 2, 70 Gasket 2-1 Restraint part 2-2 Unrestricted part 4, 4-1, 4-2, 4-3, 4-4, 4a, 4b Inner cut 6, 6-1, 6-2, Vertical surface section 7-1, 7-2, 9-1, 9-2 Opposite surface part 8-1 Inner peripheral surface section 8-2 Outer peripheral surface section 9-11, 9-12 surface section 12 Flange fastening part 14-1, 14-2 pipeline 16-1, 16-2 flange 18 Volts 20 Nut 22 Gasket seat 24 Gap 26 Gasket Management System 28 Strain Sensor 30 Management Server 32 Information presentation section 34 processors 36 Memory section 38 Input / Output (I / O) Section 40 Communications Department 42 Gasket Management Database (DB) 44 Gasket Management File 46 Gasket Information Department 47 Innercut Information Department 48 Time Information Department 50 Load Information Section 52 Strain sensor information section 54 Detection Information Section 56 Judgment Information Department 58 History Information Department 60-1, 60-2, 60-3, 60-4 Shape observation section 701 Outer ring 702 Gasket body 703 Inner Circle

Claims

1. A gasket having an inner cut whose shape changes in response to a load applied to a restrained portion restrained between flanges and whose long side extends along the periphery of a non-restrained portion adjacent to the restrained portion, installing the gasket; applying a load between the flanges to the gasket restrained between the flanges; and measuring a shape of the inner cut that has changed due to the load. A control method for controlling fastening between the flanges based on a change in shape of the inner cut.

2. The management method described in Claim 1, characterized in that the gasket is used so that the opposing surfaces constituting the long side of the inner cut come into contact with each other due to a change in the shape of the inner cut caused by the load.

3. 3. The management method according to claim 2, further comprising the step of acquiring minimum point information from a change in shape of the inner cut.

4. A measuring means for measuring the shape of an inner cut whose long side extends along the periphery of a gasket that is restrained between flanges and receives a load; a management server that generates management information for managing fastening of the gasket based on a change in the shape of the inner cut; an information presenting unit that presents the management information; A management system comprising:

5. A function for acquiring shape information of an inner cut whose long side extends along the periphery of a gasket that is restrained between flanges and receives a load; a function of generating management information for managing fastening of the gasket based on the shape information; a function of presenting the management information; A program to realize this on a computer.

6. The inner cut is such that the opposing surfaces constituting the long side come into contact with each other due to a change in shape of the inner cut caused by the load, The program according to claim 5, further comprising a function of acquiring minimum point information from a change in shape of the inner cut by the computer.

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