Detection method and tool for obtaining performance parameters of sealing element

Abstract

The invention relates to the technical field of sealing, in particular to a detection method for obtaining performance parameters of a sealing element and a tool thereof. According to the detection method, a tool with an open sealing groove structure is used for assembling the sealing element, the problem that the sealing element is prone to being damaged during disassembly and assembly is solved, off-line detection is carried out on the naturally-placed sealing element, the dynamic sealing element and the static sealing element, the defects existing in on-line detection are overcome, and the detection efficiency is improved. And thirdly, the influence of swelling on the abrasion loss is reduced and the detection precision of the abrasion loss of the sealing element is improved by comprehensively processing the detection results of the three types of sealing elements of natural placement, dynamic sealing and static sealing.

Description

Technical Field

[0001] The present invention relates to the technical field of sealing, and in particular to a detection method and tooling thereof for obtaining performance parameters of a sealing component. Background Art

[0002] At present, the evaluation of seals' wear resistance and compression set resistance is mainly based on the performance of their raw materials.

[0003] The main purpose of rubber wear testing is to simulate and quantify the surface material loss of rubber products caused by various factors in the use environment, evaluate their wear resistance, and ensure the durability, reliability and service life of the products. The test items of rubber wear testing are mainly the following four items: a. Wear amount: the mass loss of rubber products after a certain period of wear under specified conditions; b. Wear rate: the amount of wear of rubber products per unit time; c. Wear resistance index: the ratio of the wear resistance of rubber products to the wear resistance of standard samples; 4. Wear morphology: by observing the surface morphology of rubber products after wear, analyze their wear mechanism and degree of wear. Several commonly used standard test methods: Akron wear test, Shaopoer wear test, DIN wear test, Taber wear test, tensile wear test. These test methods use the above four test items to evaluate the wear resistance of rubber materials under certain working conditions, but they cannot perfectly evaluate the wear resistance of the seal ring in actual working conditions.

[0004] The ability of rubber to resist permanent deformation during compression is an important indicator to measure the ability of rubber products to recover after long-term compression, which is directly related to the application effect and service life of rubber products. At present, the permanent deformation degree of elastic materials (such as rubber and elastomers) under continuous pressure is mainly measured through the "permanent compression deformation test". This test determines the amount of permanent deformation by measuring the degree of recovery of the material after the pressure is applied. It is usually carried out at different temperatures to evaluate the performance of the material in various environments.

[0005] The evaluation of plastic wear resistance is similar to that of rubber wear resistance, which is mainly completed through a series of standardized test methods. At present, the evaluation of plastic wear resistance is mainly measured by its PV value. The PV value of plastic is a comprehensive performance indicator, which reflects the friction performance and load-bearing capacity of plastic materials under specific conditions. However, environmental factors such as the working temperature, humidity, and chemical media of plastics will also affect its PV value. At present, the PV value of plastics can only be used as a measurement standard, and it is difficult to form a strict implementation criterion.

[0006] The compression permanent deformation of plastics is also evaluated by simulating the long-term pressure that the material is subjected to in actual use, so as to evaluate the degree of permanent deformation of the plastic under pressure. However, in actual use, plastic sealing rings often experience creep and extrusion due to the influence of temperature and pressure. When designing sealing rings, the material selection of sealing rings is often based on engineering experience, which is not very reliable.

[0007] At present, the existing test methods for performance testing and life assessment of seals have some shortcomings, making it difficult to comprehensively and accurately assess the wear and deformation of seals under actual working conditions.

[0008] One type of existing technology is offline testing, which usually involves fixing the seal on a tooling and testing the seal's performance under a single test condition. This type of testing method is prone to damage the seal when assembling or removing the seal from a traditional tooling, affecting the accuracy of the test results. In addition, this type of testing method is difficult to effectively distinguish between the amount of wear and swelling of the seal, resulting in deviations in life assessment.

[0009] Another type of existing technology is online detection, which usually involves installing a monitoring device at the sealing structure or embedding a micro-monitoring device in the main body of the seal. Online monitoring makes up for the defect that offline detection cannot fully simulate complex working conditions, but it is technically difficult to install such monitoring devices as sensors at the sealing structure or in the main body of the seal, and installing a micro-detection device in the main body of the seal requires destroying the structure of the seal itself, which affects its compression permanent deformation, anti-aging performance, sealing performance and other performance parameters, affects the detection results, and further affects its service life.

[0010] Therefore, the existing offline detection technology has the disadvantage that the traditional tooling is easy to cause damage to the seal during disassembly and assembly, and the existing online detection technology has the disadvantage that it is difficult to install the monitoring device at the sealing structure, and embedding the micro detection device in the main body of the seal will lead to low accuracy of the detection result. In view of the disadvantages of the existing technology, the members of the technical team of the present invention actively study new detection methods that are different from the existing technology. Summary of the invention

[0011] In view of the shortcomings of the prior art, the present invention proposes a detection method and tooling for obtaining the performance parameters of seals. First, the seals are assembled through a tooling with an open sealing groove structure to solve the problem of easy damage to the seals during disassembly and assembly. Second, the three types of seals, namely natural placement, dynamic sealing and static sealing, are tested offline to avoid the shortcomings of online testing. Third, the test results of the three types of seals, namely natural placement, dynamic sealing and static sealing, are comprehensively processed to reduce the influence of swelling on wear and improve the detection accuracy of seal wear.

[0012] First, the present invention provides a detection method for obtaining performance parameters of a seal.

[0013] The detection method comprises the following operations:

[0014] Firstly, according to the actual motion conditions and the actual sealing structure, two sets of tooling with open sealing groove structures are designed, one set is a dynamic tooling for simulating the dynamic sealing of the seal, and the other set is a static tooling for simulating the static sealing of the seal;

[0015] Then, three types of seals, namely natural placement, dynamic seals and static seals, are selected from the same batch of seals for testing. After the seals of dynamic seals are assembled to the dynamic tooling and the seals of static seals are assembled to the static tooling, synchronous tests are carried out under test conditions simulating actual working conditions.

[0016] As time goes by, at each sampling moment, the performance of three types of seals, namely, natural placement, dynamic sealing, and static sealing, is tested respectively, and the performance parameters of the seals at that sampling moment are obtained by comparing and analyzing the test results;

[0017] Performance testing includes endurance testing to detect wear.

[0018] In some embodiments, when the wear amount is detected by the durability test, the weights of three types of seals, namely, natural placement, dynamic seal, and static seal, are obtained at the same sampling time;

[0019] First, the weight of the statically sealed seal is divided by the weight of the naturally placed seal to obtain the swelling weight gain rate at the sampling time;

[0020] Then, the weight of the seal of the dynamic seal is divided by the swelling weight gain rate to obtain the net weight of the seal after wear at the sampling time;

[0021] Then, the net weight of the seal after wear is subtracted from the weight of the seal in a natural position to obtain the wear amount of the seal at the sampling moment.

[0022] In some embodiments, during the durability test, the wear amount of the seal corresponding to a series of sampling moments is obtained according to the duration, and a wear amount-durability duration curve is obtained to predict the wear amount of the same batch of seals with the same actual motion conditions and the same actual sealing structure.

[0023] In some embodiments, the performance test items also include a deformation observation test for detecting a deformation state.

[0024] In some embodiments, when the deformation state is detected through a deformation observation test, the surface morphologies of three types of seals, namely, naturally placed, dynamic seals, and static seals, are magnified and observed through a microscope, and the deformation of the seals is compared, analyzed, and recorded.

[0025] In some embodiments, when the deformation state is detected through a deformation observation test, the cross-sectional morphology and size of the three types of seals, namely, naturally placed, dynamic seals, and static seals, after cutting are magnified and observed through a microscope, and are compared and analyzed with the design dimensions respectively, and the deformation of the seals is recorded.

[0026] In some embodiments, the performance test items also include a pressure test for testing sealing ability.

[0027] In some embodiments, when the sealing ability is tested through a pressure resistance test, three types of seals, namely natural placement, dynamic sealing, and static sealing, are respectively installed on a piston rod with a pressure sensor. The pressure stress value of each seal is collected by the pressure sensor, and the pressure stress values ​​of the seal corresponding to a series of sampling moments are obtained according to the time length to obtain a pressure stress-endurance time curve, which is used to predict the sealing performance of the same batch of seals with the same actual motion conditions and the same actual sealing structure.

[0028] Second, the present invention also provides a tool for assembling a sealing member to implement the above detection method. The tool has an open sealing groove structure, and the sealing member is assembled at the open sealing groove.

[0029] In some embodiments, the tooling includes a cylinder and a piston rod that are sleeved together and have an open sealing groove structure. The seal is assembled on the piston rod through the open sealing groove and coupled with the piston rod or the cylinder.

[0030] In some embodiments, the tooling, in addition to the cylinder and the piston rod, also includes an end cap, a bushing, a piston retaining ring, and a gasket;

[0031] The end cap is locked to the open end of the cylinder;

[0032] The piston retaining ring is locked and installed on the head of the piston rod to form an open sealing groove. The piston retaining ring and the piston rod are connected into a whole and then movably installed in the cylinder. The open sealing groove formed by the piston retaining ring and the piston rod is combined with the inner wall of the cylinder to form a complete sealing groove.

[0033] The cylinder and bushing are both provided with open sealing grooves;

[0034] The bushing and gasket are installed in the open sealing groove at the open end of the cylinder in sequence and locked by locking the end cover installed on the cylinder;

[0035] The piston rod extends from the open end of the cylinder, so that the outer wall surface of the piston rod, the inner wall surface of the cylinder, the bushing, the gasket, and the end cover together form a complete sealing groove;

[0036] The piston retaining ring and the piston rod can move or rotate along the axis inside the cylinder.

[0037] In some embodiments, the end cap is threadedly connected to the barrel for locking into one piece.

[0038] In some embodiments, the piston retaining ring is threadedly connected to the piston rod for locking into one piece.

[0039] Compared with the prior art, the present invention has the following advantages and beneficial effects.

[0040] (1) The detection method for obtaining the performance parameters of the seal proposed in the present invention solves the problem that the seal is easily damaged during disassembly and assembly by assembling the seal with a tooling having an open sealing groove structure.

[0041] (2) The detection method for obtaining the performance parameters of the seal proposed in the present invention avoids the shortcomings of online detection by performing offline detection on three types of seals: natural placement, dynamic sealing, and static sealing.

[0042] (3) The detection method for obtaining the performance parameters of the seal proposed in the present invention reduces the influence of swelling on the wear amount and improves the detection accuracy of the seal wear amount by comprehensively processing the detection results of three types of seals: natural placement, dynamic sealing, and static sealing.

[0043] (4) The detection method for obtaining the performance parameters of the seal proposed by the present invention is to

[0044] (5) The tooling proposed in the present invention is designed according to the actual motion conditions and the actual sealing structure, which is more in line with the actual working state of the seal. In addition, an open sealing groove for assembling the seal is provided on the tooling to reduce the risk of damage to the seal during disassembly and assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments with reference to the following drawings:

[0046] Figure 1 It is a schematic diagram of a typical structure of the tooling described in the present invention.

[0047] Among them, 1. end cover; 2. bushing; 3. cylinder; 4. piston rod; 5. piston retaining ring; 6. gasket; 7. seal. DETAILED DESCRIPTION

[0048] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0049] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, it is limited that "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly including one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0050] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0051] Embodiment 1:

[0052] In the prior art, a closed groove or a stepped groove is usually used to assemble the seal 7, which makes it easy to cause damage to the seal 7 during disassembly and assembly, and the test results cannot distinguish between the swelling amount and the wear amount, resulting in low accuracy of the test results.

[0053] In view of the defects existing in the prior art, this embodiment discloses a detection method for obtaining the performance parameters of the seal 7. The seal 7 is assembled by independently designed tooling to solve the problem of easy damage to the seal 7 during disassembly and assembly. Three types of seals 7, namely natural placement, dynamic sealing and static sealing, are selected from the same batch of seals 7 for experimental control, so as to distinguish the swelling amount and the wear amount, improve the detection accuracy, and thus more accurately predict the service life of this batch of seals 7.

[0054] The detection method for obtaining the performance parameters of the seal 7 provided in this embodiment is as follows: first, according to the actual motion working conditions and the actual sealing structure, two sets of tooling with open sealing groove structures are designed, one set is a dynamic tooling for simulating the dynamic sealing of the seal 7, and the other set is a static tooling for simulating the static sealing of the seal 7; the tooling includes a cylinder 3 and a piston rod 4 which are sleeved with each other, and the seal 7 is assembled on the piston rod 4 through the open sealing groove and coupled with the piston rod 4 or the cylinder 3;

[0055] Then, three types of seals 7, namely, natural placement, dynamic sealing, and static sealing, are selected from the same batch of seals 7 for testing. After the seals 7 for dynamic sealing are assembled to the dynamic tooling, and the seals 7 for static sealing are assembled to the static tooling, synchronous testing is performed under test conditions simulating actual working conditions.

[0056] As time changes, at each sampling moment, the performance of the three types of seals 7, namely, natural placement, dynamic sealing, and static sealing, is tested respectively, and the performance parameters of the seals 7 at the sampling moment are obtained by comparing and analyzing the test results.

[0057] It should be noted that the same batch of seals 7 refers to multiple sets of seals 7 made of the same material and processed according to the same set of design drawings. The number of seals 7 in "a set of seals 7" here can be multiple or one, and usually refers to seals 7 installed along the same axial direction in the same independent component, such as: a group of seals 7 designed along the axial direction of the piston rod 4 in the actuator of a single cylinder 3. The seals 7 for natural placement are marked and placed naturally for storage. The seals 7 used to achieve dynamic sealing are assembled in the dynamic tooling to form a sealing structure that is the same as the actual sealing structure. During the test, the piston rod 4 in the dynamic tooling moves relative to the cylinder 3, such as: reciprocating motion along the central axis, and rotational motion selected along the central axis, so that the two parts constituting the sealing coupling move relative to each other, and the seals 7 are in a dynamic sealing state. The seals 7 used to achieve static sealing are assembled in the dynamic tooling to form a sealing structure that is the same as the actual sealing structure. During the test, the two parts constituting the sealing coupling do not move relative to each other, and the seals 7 are in a static sealing state.

[0058] Furthermore, based on the technical concept of the above detection method, multiple series of seals 7 with different materials, different sizes, different installation structures or different working conditions can be tested, so as to predict the service life of the corresponding series of seals 7.

[0059] Furthermore, based on the technical concept of the above detection method, the detection items applicable to the detection method include but are not limited to: endurance test for detecting wear, deformation observation test for detecting deformation state, and pressure test for detecting sealing ability. One or more detection items can be designed according to actual needs.

[0060] Embodiment 2:

[0061] This embodiment describes the specific operations of several typical detection items based on the embodiment 1.

[0062] The first typical test item: durability test to detect wear.

[0063] When the wear amount is detected through the durability test, at the same sampling time, the weights of the three types of seals 7, namely, naturally placed, dynamically sealed, and static sealed, are obtained respectively; the weight of the static sealed seal 7 is divided by the weight of the naturally placed seal 7 to obtain the swelling weight gain rate at the sampling time; then, the weight of the dynamic sealed seal 7 is divided by the swelling weight gain rate to obtain the net weight of the seal 7 after wear at the sampling time; then, the weight of the naturally placed seal 7 is subtracted from the net weight of the seal 7 after wear to obtain the wear amount of the seal 7 at the sampling time.

[0064] During the durability test, the above operation is repeated to obtain the wear amount of the seal 7 corresponding to a series of sampling moments according to the duration, and a wear amount-durability duration curve is obtained to predict the wear amount of the same batch of seals 7 with the same actual motion conditions and the same actual sealing structure.

[0065] The second typical test item: deformation observation test used to detect deformation status.

[0066] When the deformation state is detected by the deformation observation test, the surface morphologies of the three types of seals 7, namely, naturally placed, dynamic seals, and static seals, are magnified and observed through a microscope, and the deformation conditions of the seals 7 are compared, analyzed, and recorded.

[0067] When the deformation state is detected through the deformation observation test, the cross-sectional morphology and size of the three types of seals 7 after cutting, namely, natural placement, dynamic sealing, and static sealing, are magnified and observed through a microscope, and compared and analyzed with the design dimensions respectively, and the deformation of the seals 7 is recorded.

[0068] When the deformation state is detected, the wear amount of the seal 7 corresponding to a series of sampling moments is obtained according to the time length, and a law of change of the deformation state with time length is obtained, which is used to predict the deformation state of the same batch of seals 7 with the same actual motion conditions and the same actual sealing structure.

[0069] The third typical test item: pressure test used to test sealing ability.

[0070] When the sealing ability is tested through a pressure test, three types of seals 7, namely, natural placement, dynamic sealing, and static sealing, are respectively installed on a piston rod 4 with a pressure sensor, and the pressure stress value of each seal 7 is collected through the pressure sensor.

[0071] During the pressure test, the compressive stress values ​​of the seal 7 corresponding to a series of sampling moments are obtained according to the duration, and a compressive stress-endurance duration curve is obtained, which is used to predict the sealing performance of the same batch of seals 7 with the same actual motion conditions and the same actual sealing structure.

[0072] The detection method described in Example 1 is used to simulate the actual working condition of the seal 7, and then the seal 7 is subjected to offline detection of various detection items to obtain the required performance parameters, thereby estimating the sealing performance and service life of the seal 7 during actual use. It can effectively optimize the corresponding sealing structure for products with different working conditions, which is very effective in improving the sealing ability and service life of the product and ensuring product safety.

[0073] The other parts of this embodiment are the same as those of Embodiment 1, and thus will not be described in detail.

[0074] Embodiment 3:

[0075] Based on Example 1 or Example 2, this embodiment takes the seal 7 in the single-rod actuator as the object of performance testing, and specifically describes the testing method and the tooling used. A plurality of seals 7 distributed along the axial direction of the piston rod 4 in a single-rod actuator is a set of seals 7. The same batch of seals 7 refers to multiple sets of seals 7 made of the same material; the same batch of seals 7 can be processed in the same batch or in different batches; the same batch of seals 7 can be processed by the same group of processing equipment or by different groups of processing equipment. There are two main basic conditions for being "the same batch of seals 7": one is that the processing materials are the same, and the other is that the seals 7 assembled in the same position in the actual installation structure have the same structure and size. Here, "the same structure and size" specifically refers to "the same design structure and design size, ignoring the processing errors caused by actual processing."

[0076] The detection method described in this embodiment includes the following steps.

[0077] Step S1: According to the actual sealing structure and the movement condition of the piston rod 4 in the cylinder 3, the following is designed: Figure 1 The tooling shown is designed with an open sealing groove structure to facilitate the assembly of the seal 7 into the open sealing groove; two sets of tooling with the same structure and size are processed: one set is used as a dynamic tooling and the other set is used as a static tooling; during the test of the dynamic tooling, the piston rod 4 performs reciprocating and / or rotational motion in the cylinder 3 to simulate the motion state of the actual working conditions, thereby simulating the dynamic sealing state of the seal 7; during the test of the static tooling, the piston rod 4 is stationary relative to the cylinder 3, thereby simulating the static sealing state of the seal 7.

[0078] Step S2, selecting three sets of seals 7 with the closest structural dimensions from the same batch of seals 7 measured in advance: one set of seals 7 is assembled in the dynamic tooling, one set of seals 7 is assembled in the static tooling, and the third set of seals 7 is marked and placed naturally.

[0079] Step S3, install the dynamic tooling with the seal 7 assembled and the static tooling with the seal 7 assembled on the same test bench, and connect the two sets of tooling in parallel, that is, connect all the same nozzles in parallel, the only difference between the two sets of tooling is that one is a dynamic tooling and the other is a static tooling.

[0080] After step S4 and step S3 are completed, the two sets of sealing members 7 assembled in the tooling are tested simultaneously according to the testing requirements of the product.

[0081] Step S4a, taking the durability test as an example, after the test is completed, the two sets of seals 7 are disassembled from their respective tooling, and the dynamic seal seals 7 and the static seal seals 7 are marked respectively; and the three seals 7 in the same sealing position of the three sets of seals 7, namely, natural placement, dynamic seal, and static seal, are taken as a group of seals 7 to be tested. Due to the advantage of the open sealing groove, the seals 7 to be tested will not be damaged due to disassembly. Next, weigh three seals 7 in a group of seals 7 to be tested, record the weight of the naturally placed seal 7 as M1, the weight of the dynamic seal 7 as M2, and the weight of the static seal 7 as M3; first, divide the weight M3 of the static seal 7 by the weight M1 of the naturally placed seal 7 to obtain the swelling weight gain rate R of the seal 7 after the test; then divide the weight M2 of the dynamic seal 7 by the swelling weight gain rate R to obtain the net weight Net of the dynamic seal 7 after wear; then subtract the net weight Net of the dynamic seal 7 after wear from the weight M1 of the naturally placed seal 7 to obtain the wear amount W. Repeat the durability test, and use the same operation to obtain the wear amount of the seal 7 at the sealing position after different lengths of time, so as to obtain a wear amount-durability length curve. Subsequent products with the same working conditions and the same sealing structure parameters can use this curve to estimate the life of the seal 7.

[0082] In another specific embodiment, the above-mentioned durability test is repeated, and the test durations are 100 hours, 200 hours, 300 hours, 400 hours and 500 hours respectively, and a relationship curve between the wear amount and the durability time is obtained to estimate the service life of the seal 7.

[0083] Step S4b, taking the pressure test as an example, a pressure sensor is built into the piston rod 4 of the tooling without changing the size of the piston rod 4, and then three seals 7 of natural placement, dynamic sealing, and static sealing at the same sealing position are installed on the piston rod 4 with a pressure sensor, and a group of three compressive stress values ​​can be obtained at each sampling moment. Repeat the pressure test, and use the same operation to obtain the compressive stress of the seal 7 at the sealing position after experiencing different lengths of time, so as to obtain a compressive stress-endurance time curve. Further analysis of the sealing pressure of the product can determine the sealing ability of the seal 7 at this time, and further estimate the life of the seal 7. Since the estimation of the life of the seal 7 based on the sealing ability is related to the customized service life standard of the product, it will not be repeated here.

[0084] Step S4c, taking the deformation observation test as an example, the surfaces of three seals 7, namely, naturally placed, dynamically sealed, and statically sealed, at the same sealing position are magnified and observed using a microscope, and the surface morphologies are compared through comparative analysis to observe the wear and deformation of the seals 7.

[0085] Step S4d, taking the deformation observation test as an example, three seals 7 of natural placement, dynamic sealing, and static sealing at the same sealing position are artificially cut into pieces, and the cross-sectional dimensions are magnified and observed with a microscope, and compared and analyzed with the design drawings, so as to obtain the deformation and wear of the seal 7. Among them, the dynamic seal seal 7 is compared with the natural seal 7, and the permanent deformation of the seal 7 can be obtained.

[0086] The test items can be selected according to actual needs, such as: high temperature test, low temperature test, pressure test, durability test, etc., which are not listed here one by one.

[0087] In another specific implementation, structural parameters of the seal 7, such as hardness, size, etc., are changed, and tests are conducted under the same test conditions, and the sealing structure with the best service life is determined based on the test results.

[0088] The other parts of this embodiment are the same as those of Embodiment 1 or Embodiment 2, and thus will not be described in detail.

[0089] Embodiment 4:

[0090] This embodiment provides a tool for testing the seal 7. The tool has an open seal groove structure, and during the test, the seal 7 is assembled in the open seal groove, and the structural characteristics of the open seal groove are used to effectively avoid the problem of damage to the seal 7 caused by disassembly and assembly.

[0091] Specifically, if Figure 1The tooling shown includes an end cover 1, a bushing 2, a cylinder 3, a piston rod 4, a piston retaining ring 5, and a gasket 6. The tooling itself has a structure with five open sealing grooves: the end cover 1 itself is provided with an open sealing groove, which is recorded as the first open sealing groove; the bushing 2 itself is provided with an open sealing groove, which is recorded as the second open sealing groove; the open end of the cylinder 3 is provided with an open sealing groove, which is recorded as the third open sealing groove; two piston retaining rings 5 ​​are locked on the plug head of the piston rod 4, one on the left and one on the right, to form two open sealing grooves, which are recorded as the fourth open sealing groove and the fifth open sealing groove.

[0092] Figure 1 The tooling shown simulates the working condition of a single-rod actuator. The figure shows five seals 7, which are respectively installed in the first open seal groove, the second open seal groove, the third open seal groove, the fourth open seal groove, and the fifth open seal groove. After the piston retainer 5 is locked on the piston rod 4 and connected as a whole, it is movably installed in the inner cavity of the cylinder 3. The open end of the cylinder 3 is successively covered with the bushing 2, the gasket 6, and the end cover 1, and the bushing 2 is locked in the third open seal groove through the end cover 1. The gasket 6 arranged between the bushing 2 and the end cover 1 plays a role in preventing loosening. After the seals 7 are assembled on the tooling, the first open seal groove, the second open seal groove, the third open seal groove and the outer wall surface of the piston rod 4 respectively form three complete seal grooves, and the fourth open seal groove and the fifth open seal groove and the inner wall surface of the cylinder 3 respectively form two complete seal grooves.

[0093] Processing two sets of Figure 1 The tooling shown. When one set of tooling is assembled with the seal 7 for testing, the piston rod 4 moves relative to the cylinder 3, and can only reciprocate along the center axis, can only rotate with the center axis as the rotation axis, and can also perform a superimposed motion of linear reciprocating motion and rotational motion at the same time; at this time, the set of tooling is a dynamic tooling, and the seal 7 assembled in the dynamic tooling is in a dynamic sealing state. When another set of tooling is assembled with the seal 7 for testing, the piston rod 4 is stationary relative to the cylinder 3; at this time, the set of tooling is a static tooling, and the seal 7 assembled in the dynamic tooling is in a static sealing state.

[0094] The other parts of this embodiment are the same as those of the above embodiment and will not be described in detail.

[0095] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A detection method for obtaining performance parameters of a seal, characterized in that: Firstly, according to the actual motion conditions and the actual sealing structure, two sets of tooling with open sealing groove structures are designed, one set is a dynamic tooling for simulating the dynamic sealing of the seal, and the other set is a static tooling for simulating the static sealing of the seal; Then, three types of seals, namely natural placement, dynamic seals and static seals, are selected from the same batch of seals for testing. After the seals of dynamic seals are assembled to the dynamic tooling and the seals of static seals are assembled to the static tooling, synchronous tests are carried out under test conditions simulating actual working conditions. As time goes by, at each sampling moment, the performance of three types of seals, namely, natural placement, dynamic sealing, and static sealing, is tested respectively, and the performance parameters of the seals at that sampling moment are obtained by comparing and analyzing the test results; The performance test items include a durability test for detecting the amount of wear.

2. A detection method for obtaining seal performance parameters according to claim 1, characterized in that: When the wear amount is detected through the durability test, at the same sampling time, the weights of the three types of seals, namely, naturally placed, dynamic seals, and static seals, are obtained respectively; first, the weight of the static seal is divided by the weight of the naturally placed seal to obtain the swelling weight gain rate at the sampling time; then, the weight of the dynamic seal is divided by the swelling weight gain rate to obtain the net weight of the seal after wear at the sampling time; then, the weight of the naturally placed seal is subtracted from the net weight of the seal after wear to obtain the wear amount of the seal at the sampling time.

3. A detection method for obtaining seal performance parameters according to claim 2, characterized in that: During the durability test, the wear amount of the seal corresponding to a series of sampling moments is obtained according to the duration, and a wear amount-durability duration curve is obtained, which is used to predict the wear amount of the same batch of seals with the same actual motion conditions and the same actual sealing structure.

4. A detection method for obtaining seal performance parameters according to claim 1, characterized in that: The performance test items also include a deformation observation test for detecting the deformation state.

5. A detection method for obtaining performance parameters of a seal according to claim 4, characterized in that: When the deformation state is detected through deformation observation test, the surface morphology of three types of seals, namely natural placement, dynamic seal and static seal, is observed and magnified through a microscope, and the deformation of the seals is compared, analyzed and recorded.

6. A detection method for obtaining seal performance parameters according to claim 4, characterized in that: When the deformation state is detected through deformation observation test, the cross-sectional morphology and size of the three types of seals after cutting, namely natural placement, dynamic seal and static seal, are observed through a microscope, and compared and analyzed with the design dimensions respectively, and the deformation of the seals is recorded.

7. A detection method for obtaining performance parameters of a seal according to claim 1, characterized in that: The performance test items also include a pressure test for testing the sealing ability.

8. A detection method for obtaining performance parameters of a seal according to claim 7, characterized in that: When testing the sealing ability through a pressure test, three types of seals, namely natural placement, dynamic seals and static seals, are respectively installed on a piston rod with a pressure sensor. The pressure stress value of each seal is collected by the pressure sensor, and the pressure stress values ​​of the seal corresponding to a series of sampling moments are obtained according to the time length to obtain a pressure stress-endurance time curve, which is used to predict the sealing performance of the same batch of seals with the same actual motion conditions and the same actual sealing structure.

9. A tool for assembling a seal to implement the detection method for obtaining performance parameters of a seal as claimed in any one of claims 1 to 8, characterized in that: The tooling has an open sealing groove structure, and the sealing member is assembled at the open sealing groove.

10. A tool according to claim 9, characterized in that: It comprises an end cover (1), a bushing (2), a cylinder (3), a piston rod (4), a piston retaining ring (5) and a gasket (6); The end cap is locked to the open end of the cylinder; The piston retaining ring is locked and installed on the head of the piston rod to form an open sealing groove. The piston retaining ring and the piston rod are connected into a whole and then movably installed in the cylinder. The open sealing groove formed by the piston retaining ring and the piston rod and the inner wall of the cylinder are combined into a complete sealing groove. The cylinder and the bushing are both provided with an open sealing groove; the bushing and the gasket are sequentially installed in the open sealing groove at the open end of the cylinder, and are locked by locking the end cover installed on the cylinder; the piston rod extends from the open end of the cylinder, so that the outer wall surface of the piston rod, the inner wall surface of the cylinder, the bushing, the gasket, and the end cover together form a complete sealing groove; The piston retaining ring and the piston rod can move or rotate along the axis inside the cylinder.

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