Test method and test device for piston life

Abstract

The present disclosure relates to the field of mechanical property testing, and more specifically, to a test method and test device for piston life. The test method for piston life includes: obtaining the design parameters of the piston; obtaining a sleeve according to the design parameters; heating the sleeve by a heating device; and applying a load spectrum to the sleeve. The technical solution of the embodiment of the present disclosure can improve the accuracy of the piston life test results to a certain extent, and further more effectively evaluate the influence of various design parameters on the piston life and mechanism, thereby realizing the prediction of the service state and life of pistons with different design parameters in internal combustion engines.

Description

Technical Field

[0001] The present disclosure relates to the field of mechanical property testing, and in particular to a testing method and a testing device for piston life. Background Art

[0002] The piston in an internal combustion engine is an important part that affects the working performance of the internal combustion engine. When the piston reciprocates in the internal combustion engine cavity, it is subjected to various mechanical loads. In addition, due to the limited heat dissipation conditions at the top of the piston, the temperature gradient between the piston head and the piston skirt is large, causing the piston to be affected by thermal stress. These complex stresses can cause a series of failures such as skirt deformation, cracking, perforation, and increased wear of the piston, which in turn affects the working reliability of the internal combustion engine. Therefore, it is necessary to test and evaluate the life of the piston in the internal combustion engine.

[0003] The life of a piston is affected by its geometric dimensions, shape, material, and processing technology. When studying the life of a piston, due to the high cost of using a real piston for testing, a simulated test piece is generally used instead of a real piston for testing. However, the existing simulated test pieces for studying the life of a piston are mostly standard test pieces with regular shapes, without considering the impact of the geometric dimensions and shape of the piston itself on the test, resulting in inaccurate test results, making it difficult to effectively evaluate the laws and mechanisms of the impact of various design parameters on the life of the piston, and unable to meet the requirements for predicting the service status and life of pistons with different design parameters in internal combustion engines.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] The purpose of the present disclosure is to provide a piston life test method and a test device, so as to improve the accuracy of the piston life test results at least to a certain extent.

[0006] According to a first aspect of the present disclosure, a piston life test method is provided, which comprises:

[0007] Obtain design parameters of the piston;

[0008] Obtaining a sleeve according to design parameters;

[0009] heating the sleeve by using a heating device;

[0010] Apply a load spectrum to the sleeve.

[0011] In an exemplary embodiment of the present disclosure, the design parameters include:

[0012] One or more parameters of the piston outer ring diameter, piston inner ring diameter, piston wall thickness, piston height, piston material, and piston processing technology; wherein the piston wall thickness is the minimum value of the piston skirt wall thickness.

[0013] In an exemplary embodiment of the present disclosure, the method further includes:

[0014] Before heating the sleeve using the heating device,

[0015] A clamping device is provided, the clamping device comprising: a clamping structure body, a cushion block, and connecting parts arranged on both sides of the clamping structure body;

[0016] Fixing the clamping structure body inside the heating device through the connecting part;

[0017] placing the sleeve on the clamping structure body;

[0018] Press the spacer onto the sleeve.

[0019] In an exemplary embodiment of the present disclosure, the main body of the clamping structure forms a concave groove structure, and both sides of the concave groove structure are tangent to the outer side wall of the sleeve;

[0020] The bottom surface of the cushion block is tangent to the outer wall of the sleeve.

[0021] In an exemplary embodiment of the present disclosure, the length of the spacer block is equal to the width of the clamping structure body, and the tangent line between the bottom surface of the spacer block and the outer wall of the sleeve is parallel to the axis of the sleeve.

[0022] In an exemplary embodiment of the present disclosure, the angle between the two side surfaces of the concave groove structure is 90°-120°.

[0023] In an exemplary embodiment of the present disclosure, the angle between the two side surfaces of the concave groove structure is 120°, and the distances from the bottom surface of the cushion block and the tangent line of the outer wall of the sleeve to the two side surfaces of the concave groove structure are equal.

[0024] In an exemplary embodiment of the present disclosure, a channel is formed on the top of the heating device, and the method further comprises:

[0025] The pad is connected to a fatigue simulation device through a channel;

[0026] The fatigue simulation device applies a load spectrum to the sleeve through a pad.

[0027] In an exemplary embodiment of the present disclosure, the method further includes:

[0028] Obtain the test environment temperature inside the heating device;

[0029] Identify the test environment temperature and send a prompt signal when the test environment temperature does not meet the preset temperature range;

[0030] When the test environment temperature reaches a threshold value, or when a test end command is received, the heating device is turned off and the application of the load spectrum to the sleeve is stopped.

[0031] According to a second aspect of the present disclosure, a piston life test device is provided, comprising:

[0032] A heating device, comprising a housing and a heat source;

[0033] A clamping device is arranged in the housing, and the clamping device comprises a clamping structure body, a cushion block and a connecting part, wherein the connecting part is arranged in the clamping structure body and connected to the housing;

[0034] The sleeve has the same design parameters as the piston, which include one or more parameters of the piston outer ring diameter, piston inner ring diameter, piston wall thickness, piston height, piston material, and piston processing technology. The sleeve is placed on the upper part of the clamping structure body, and the cushion block is pressed on the upper part of the sleeve.

[0035] In the technical solutions provided in some exemplary embodiments of the present disclosure, a sleeve is used for simulation test. On the one hand, the sleeve has a simple structure and is easy to process, which can improve the convenience of the test and reduce the test cost. On the other hand, when studying the influence of design parameters on the life of the piston, the geometric size, shape, processing technology and other parameters of the piston itself can be introduced, thereby improving the accuracy of the piston life test results to a certain extent, and more effectively evaluating the influence of various design parameters on the life of the piston. The law and mechanism, thereby realizing the prediction of the service state and life of the piston with different design parameters in the internal combustion engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0037] In order to better understand the present disclosure, reference may be made to the embodiments shown in the following drawings. The components in the drawings are not necessarily to scale, and related elements may be omitted in order to emphasize and clearly illustrate the technical features of the present disclosure. In addition, related elements or components may have different arrangements as known in the art. In addition, in the drawings, the same reference numerals represent the same or similar components in each drawing. Among them:

[0038] Figures 1A-1C Schematically showing three different viewing angles of a sleeve according to an exemplary embodiment of the present disclosure;

[0039] Figure 2 A partial structural diagram of a piston life test device according to an exemplary embodiment of the present disclosure is schematically shown;

[0040] Figure 3 A partial structural diagram of a piston life test device according to an exemplary embodiment of the present disclosure is schematically shown;

[0041] Figure 4 A partial structural diagram of a piston life test device according to an exemplary embodiment of the present disclosure is schematically shown;

[0042] Figure 5 A flow chart schematically shows a method for testing piston life according to an exemplary embodiment of the present disclosure.

[0043] The following are the descriptions of the reference numerals:

[0044] 10. Sleeve; 20. Clamping device; 21. Clamping structure body; 211. Concave groove structure; 22. Connecting part; 23. Pad; 231. Pad connector; 30. Heating device; 31. Shell; 311. Channel; 32. Heat source; 33. Temperature detection device; 34. Safety protection device. DETAILED DESCRIPTION

[0045] The following will be combined with the accompanying drawings in the exemplary embodiments of the present disclosure to clearly and completely describe the technical solutions in the exemplary embodiments of the present disclosure. The exemplary embodiments described herein are only for illustrative purposes and are not intended to limit the scope of protection of the present disclosure. Therefore, it should be understood that various modifications and changes can be made to the exemplary embodiments without departing from the scope of protection of the present disclosure.

[0046] Unless otherwise specified or explained, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, an integral connection, an electrical connection, or a signal connection; "connection" can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meanings of the above terms in this disclosure can be understood according to specific circumstances.

[0047] Further, in the description of the present disclosure, it should be understood that the directional words such as "upper", "lower", "inner", "outer" and the like described in the example embodiments of the present disclosure are only for convenience, for example, the description is based on the angles shown in the accompanying drawings, and should not be understood as limiting the example embodiments of the present disclosure. It should also be understood that in the context, when it is mentioned that an element or feature is connected to another element (one or more) "upper", "lower", or "inner", "outer", it can not only be directly connected to the other (one or more) elements "upper", "lower", "inner", "outer", but also can be indirectly connected to the other (one or more) elements "upper", "lower", "inner", "outer" through an intermediate element.

[0048] The terms "a", "an", "the", and "said" are used to indicate the presence of one or more elements / components / etc.; the terms "including" and "having" are used to express an open-ended inclusion and mean that additional elements / components / etc. may exist in addition to the listed elements / components / etc.; the terms "first" and "second", etc. are used merely as labels and are not intended to limit the quantity of their objects.

[0049] The piston is the core component of the internal combustion engine and plays a very important role in the working process of the internal combustion engine. Its life affects the overall reliability of the internal combustion engine. Especially the piston of the diesel engine, compared with the gasoline engine piston, has a greater heat load during operation, a greater skirt force, and a more complex structure. Therefore, the life assessment of the diesel engine piston is particularly important in the overall reliability design of the diesel engine.

[0050] The present disclosure provides a piston life test device, comprising:

[0051] The heating device 30 includes a housing 31 and a heat source 32;

[0052] The clamping device 20 is disposed in the housing 31. The clamping device 20 includes a clamping structure body 21, a cushion block 23 and a connecting portion 22. The connecting portion 22 is disposed in the clamping structure body 21 and connected to the housing 31.

[0053] The sleeve 10 has the same design parameters as the piston, including the outer ring diameter of the piston, the inner ring diameter of the piston, the wall thickness of the piston, the height of the piston, the material of the piston, and one or more parameters in the piston processing technology. The sleeve 10 is placed on the upper part of the clamping structure body 21, and the gasket 23 is pressed on the upper part of the sleeve 10.

[0054] A sleeve life test device according to an exemplary embodiment of the present disclosure provides a sleeve 10 with the same design parameters as the piston for life testing. The sleeve has a simple structure and is easy to process, which improves the convenience of the test and reduces the test cost. At the same time, the sleeve and the piston have more similar features in geometry and process, which can improve the accuracy of the piston life test results to a certain extent. The present disclosure also provides a clamping device 20 and a heating device 30 matched with the sleeve to cooperate with the sleeve to complete the test and achieve the above-mentioned beneficial effects.

[0055] In an exemplary embodiment of the present disclosure, reference Figures 1A-1C As shown, the outer diameter of the sleeve 10 Inner ring diameter One or more design parameters of the wall thickness Δt, height h, material, and processing technology are the same as those of the piston, so that the sleeve 10 has a simple structure compared to the piston, which can reduce the test cost, and can also be consistent with the piston in terms of geometric size, shape, and processing technology, thereby improving the accuracy of the piston life test results.

[0056] In an exemplary embodiment of the present disclosure, the outer diameter of the sleeve 10 is Inner ring diameter One or more design parameters of the wall thickness Δt, height h, material, and processing technology are the same as those of the diesel engine piston.

[0057] In an exemplary embodiment of the present disclosure, reference Figure 2 As shown, the clamping structure body 21 forms a concave groove structure 211, and both sides of the concave groove structure 211 are tangent to the outer wall of the sleeve 10. When the piston life test device disclosed in the present invention is used for testing, the concave groove structure 211 can prevent the cylindrical sleeve 10 from rolling, thereby improving the accuracy of the test. Specifically, the concave groove structure 211 can be a "concave" shape, a "V" shape, an inverted trapezoid or other similar shapes, and the present disclosure does not make any special restrictions on this.

[0058] In an exemplary embodiment of the present disclosure, the shape of the concave groove structure 211 is an inverted trapezoid, and the angle between the two sides of the concave groove structure 211 is 90°-120°, so that the sleeve 10 can be placed on the upper part of the clamping structure body 21 relatively stably.

[0059] In an exemplary embodiment of the present disclosure, the angle between the two sides of the concave groove structure 211 is 120°. When the piston is working in an internal combustion engine, it reciprocates in a cylindrical cavity, so it is not suitable for single-axis force. Through this angle setting, the angle between the lines of action of each force of the two sides of the concave groove structure 211 and the cushion block 23 on the sleeve 10 and its adjacent line is 120°, which is closer to the actual force condition of the piston when working, and can improve the accuracy of the test results.

[0060] In an exemplary embodiment of the present disclosure, the bottom surface of the cushion block 23 is tangent to the outer wall of the sleeve 10 , wherein the bottom surface of the cushion block 23 may be a flat surface or a curved surface.

[0061] In an exemplary embodiment of the present disclosure, the length of the cushion block 23 is equal to the width of the clamping structure body 21, and the tangent line between the bottom surface of the cushion block 23 and the outer wall of the sleeve 10 is parallel to the axis of the sleeve 10. This allows the cushion block 23 and the clamping structure body 21 to form at least three tangent lines with the sleeve 10, which are parallel to each other and have the same length, thereby improving the support stability of the sleeve 10.

[0062] In an exemplary embodiment of the present disclosure, the width of the clamping structure body 21 is greater than the height of the sleeve 10 , so that the sleeve 10 can be placed on the clamping structure body 21 more stably.

[0063] In an exemplary embodiment of the present disclosure, the distances from the bottom surface of the pad 23 and the tangent line of the outer wall of the sleeve 10 to the two sides of the concave groove structure 211 are equal. Since the pad 23 and the clamping structure body 21 are both tangent to the sleeve 10, the line of action of the force of the clamping device 20 on the sleeve 10 is perpendicular to the contact surface between the clamping device 20 and the sleeve 10 and points to the axis of the sleeve 10; the distances from the bottom surface of the pad 23 and the tangent line of the outer wall of the sleeve 10 to the two sides of the concave groove structure 211 are equal, so that the lateral forces of the clamping device 20 on the sleeve 10 offset each other, preventing the sleeve 10 from shaking or moving when the load spectrum is applied to the sleeve 10.

[0064] In an exemplary embodiment of the present disclosure, reference Figure 3 As shown, the heating device 30 includes a shell 31 and a heat source 32, wherein the shell 31 can contain the sleeve 10, and the heat source 32 heats the sleeve 10. Specifically, part or all of the shell 31 can be made of heat-insulating materials to reduce heat loss during the test and improve the heating efficiency; the shell 31 can also be made of transparent materials such as high-temperature resistant glass in part or in whole, and the sleeve 10 can be observed through the transparent material part of the shell 31 during the test. Specifically, the heat source 32 can be set inside or outside the shell 31, and the heat source 32 can be a heating wire, a heating tube or a heating lamp, which is not particularly limited in the present disclosure.

[0065] In an exemplary embodiment of the present disclosure, reference Figure 4As shown, the clamping device 20 is arranged in the shell 31 to fix the position of the sleeve 10 in the heating device 30, so as to facilitate the subsequent application of the load spectrum to the sleeve 10; the connecting portion 22 of the clamping device 20 is arranged on the clamping structure body 21 and is connected to the shell 31, wherein the connecting portion 22 can be arranged at the front and back, both sides or the top and bottom of the clamping structure body 21, and is fixedly or detachably connected to the clamping structure body 21; the connection between the connecting portion 22 and the shell 31 can be connected in a detachable manner such as bolt connection to improve the disassembly and assembly flexibility of the test device; it can also be connected in a non-detachable manner such as welding, riveting, bonding, etc. to improve the firmness of the test device and the stability of the connection.

[0066] In an exemplary embodiment of the present disclosure, reference Figure 4 As shown, a channel 311 is formed on the top of the shell 31 of the heating device 30, and the pad 23 is connected to a fatigue simulation device through the channel 311. Specifically, the pad 23 can pass through the channel 311 through the pad connector 231 to connect to the fatigue simulation device. The pad connector 231 can be a protruding part of the top of the pad 23, or a bolt or pin type fastener. The channel 311 allows the fatigue simulation device to apply a load spectrum to the sleeve 10 without entering the heating device 30, so that the thermal fatigue test can be carried out inside the heating device 30, and the volume of the heating device 30 is reduced, making the structure of the entire test device more streamlined and flexible.

[0067] The fatigue simulation device in this exemplary embodiment refers to a device that can provide a load spectrum, specifically, it can be a standard fatigue testing machine, or a dedicated piston fatigue testing machine, or other devices that can provide the required load spectrum such as a cylinder, cam, or push rod. The present disclosure does not make any special limitations on this.

[0068] In an exemplary embodiment of the present disclosure, the heating device 30 may further include a temperature detection device 33. The temperature detection device 33 may include a contact temperature sensor or a non-contact temperature sensor disposed inside or outside the heating device 30 to obtain and identify the test environment temperature. The temperature detection device 33 may also include a display screen disposed outside the heating device 30 to display the test environment temperature.

[0069] In an exemplary embodiment of the present disclosure, the heating device 30 may further include a safety protection device 34. The safety protection device 34 may be disposed outside the heating device 30 and include one or more circuit breakers, which perform a circuit breaker operation on the test device circuit according to set conditions, such as when the test environment temperature reaches a threshold value, or when the duration of the applied load spectrum reaches a preset value.

[0070] In an exemplary embodiment of the present disclosure, the piston life test device may further include a master control terminal. The master control terminal may be connected to the heating device 30 and the fatigue simulation device by wire or wirelessly, and may control the opening and closing of the heat source 32 and the fatigue simulation device, and obtain the test environment temperature sent by the temperature detection device 33 and display it on a screen.

[0071] In an exemplary embodiment of the present disclosure, a piston life test device may implement the piston life test method of the present disclosure.

[0072] The present disclosure also provides a test method for piston life, referring to Figure 5 As shown, the method may include:

[0073] Step S510, obtaining design parameters of the piston;

[0074] Step S520, obtaining the sleeve 10 according to the design parameters;

[0075] Step S530, heating the sleeve 10 by using the heating device 30;

[0076] Step S540 , applying a load spectrum to the sleeve 10 .

[0077] A sleeve life test method according to an exemplary embodiment of the present disclosure obtains design parameters of a piston, obtains a sleeve 10 according to the design parameters, and heats and applies a load spectrum to the sleeve 10. On the one hand, since the sleeve 10 has a simple structure and is easy to process, it can improve the convenience of the test and reduce the test cost. On the other hand, when studying the influence of design parameters on the piston life, the geometric size, shape, processing technology and other parameters of the piston itself can be introduced, thereby improving the accuracy of the piston life test results to a certain extent, and more effectively evaluating the influence of various design parameters on the piston life. The law and mechanism, thereby realizing the prediction of the service state and life of pistons with different design parameters in internal combustion engines.

[0078] A piston life test method according to the present disclosure is described in detail below with reference to the accompanying drawings.

[0079] In step S510, the design parameters of the piston are obtained, wherein the design parameters of the piston include the piston's geometric parameters, materials, and process parameters, such as the piston outer ring diameter, piston inner ring diameter, piston wall thickness, piston height, piston material, and piston processing technology, which are all piston design parameters and have an impact on the life of the piston.

[0080] In an exemplary embodiment of the present disclosure, design parameters of a diesel engine piston are obtained, including outer ring diameter, inner ring diameter, wall thickness, height, material, and processing technology of the diesel engine piston.

[0081] In step S520, a sleeve 10 is obtained according to the design parameters. The sleeve 10 is a hollow cylindrical structure. Specifically, a sleeve 10 having the same one or more of the above-mentioned design parameters as the piston can be obtained.

[0082] For example, refer to Figures 1A-1C As shown, the sleeve 10 is obtained according to the design parameters. When studying the influence of the processing technology on the life of the piston, the outer ring diameter of the piston can be obtained. Inner ring diameter Multiple sleeves 10 with the same wall thickness Δt, height h, and material are provided with processing techniques corresponding to pistons with different processes. Or when studying the influence of the height of the piston on the life of the piston, the outer diameter of the piston can be obtained. Inner ring diameter A plurality of sleeves 10 having the same wall thickness Δt, material, and processing technology are provided, and each of them has a height h corresponding to a plurality of pistons of different heights.

[0083] The sleeve 10 is obtained according to the design parameters of the piston for testing. On the one hand, compared with using the piston itself which is difficult to process, complex in structure and high in cost for life testing, the difficulty of obtaining the test piece is reduced, the convenience of the test is improved, and the cost of the test is reduced. On the other hand, compared with using the standard test piece for testing, the sleeve 10 has the same geometric parameters as the piston, which improves the similarity between the test piece and the piston, thereby improving the accuracy of the test results. At the same time, the structure of the sleeve 10 is similar to that of the piston, so the process parameters consistent with the piston can be used, which improves the limitations of the structure and shape of the standard test piece on the processing technology.

[0084] In an exemplary embodiment of the present disclosure, the outer diameter of the piston is obtained. Inner ring diameter Multiple sleeves 10 with the same wall thickness Δt, height h, and material are processed with different processing techniques. For example, pistons are currently mainly processed by turning, and are not polished or ground after processing. When studying the effect of grinding and polishing techniques on the life of the piston, multiple sleeves 10 are processed by turning, turning + outer wall grinding and polishing, turning + inner wall grinding and polishing, turning + outer wall grinding and polishing + inner wall grinding and polishing, and subsequent test steps are completed respectively. The test results are compared to analyze the effect of grinding and polishing techniques on the life of the piston. In this exemplary embodiment, the simulated test piece, i.e., the sleeve 10, can maintain the same processing technique as the piston and obtain consistent surface feature indicators, so that the test results more truly reflect the actual situation and improve the authenticity of the test results.

[0085] In an exemplary embodiment of the present disclosure, the minimum value of the wall thickness of the piston skirt is taken as the piston wall thickness.

[0086] In step S530, the sleeve 10 is heated by the heating device 30. Since the piston is in a temperature field when working in the internal combustion engine, the sleeve 10 is heated by the heating device 30 during the life test to simulate the temperature field of the piston. Specifically, the heating device 30 can directly heat the sleeve 10, for example, a resistance wire is provided on the sleeve 10, and the temperature of the sleeve 10 is increased after power is turned on; or it can be indirectly heated by heating the test environment to increase the air temperature. The heating device 30 can be a constant temperature heating device, for example, heating the temperature of the sleeve 10 to a fixed value; it can also be a variable temperature heating device, for example, heating the sleeve 10 according to a preset temperature change law; or it can provide the sleeve 10 with a temperature field that changes according to different positions, and the present disclosure does not make any special restrictions on this.

[0087] In an exemplary embodiment of the present disclosure, before heating the sleeve 10 by the heating device 30 in step S530, the method further includes:

[0088] A clamping device 20 is provided, the clamping device 20 comprises: a clamping structure body 21, a cushion block 23 and a connecting portion 22 provided on the clamping structure body 21;

[0089] The clamping structure body 21 is fixed inside the heating device 30 through the connecting portion 22;

[0090] Place the sleeve 10 on the clamping structure body 21;

[0091] The spacer 23 is pressed onto the sleeve 10 .

[0092] By providing the clamping device 20 and arranging the clamping device 20 in the heating device 30 and placing the sleeve 10 on the clamping device 20 , the position of the sleeve 10 can be fixed and the subsequent application of the load spectrum to the sleeve 10 is facilitated.

[0093] In an exemplary embodiment of the present disclosure, the clamping structure body 21 forms a concave groove structure 211, and both sides of the concave groove structure 211 are tangent to the outer wall of the sleeve 10. Specifically, the concave groove structure 211 can be "concave", "V", inverted trapezoidal or other similar shapes. When the sleeve 10 is placed on the clamping structure body 21, the concave groove structure 211 can prevent the cylindrical sleeve 10 from rolling, and when the load spectrum is applied to the sleeve 10 later, the force position can be kept unchanged, thereby improving the accuracy of the test.

[0094] In an exemplary embodiment of the present disclosure, the shape of the concave groove structure 211 is an inverted trapezoid, and the angle between the two sides of the concave groove structure 211 is 90°-120°, so that the sleeve 10 can be placed on the upper part of the clamping structure body 21 relatively stably.

[0095] In an exemplary embodiment of the present disclosure, the angle between the two side surfaces of the concave groove structure 211 is 120°, so that the angle between the line of action of each force of the two side surfaces of the concave groove structure 211 and the cushion block 23 on the sleeve 10 and its adjacent line is 120°, which is closer to the actual force condition of the piston when working, thereby improving the accuracy of the test results.

[0096] In an exemplary embodiment of the present disclosure, the bottom surface of the cushion block 23 is tangent to the outer wall of the sleeve 10 , wherein the bottom surface of the cushion block 23 may be a flat surface or a curved surface.

[0097] In an exemplary embodiment of the present disclosure, the length of the cushion block 23 is equal to the width of the clamping structure body 21 , and the tangent line between the bottom surface of the cushion block 23 and the outer wall of the sleeve 10 is parallel to the axis of the sleeve 10 .

[0098] In an exemplary embodiment of the present disclosure, the width of the clamping structure body 21 is greater than the height of the sleeve 10 , so that the sleeve 10 can be placed on the clamping structure body 21 more stably.

[0099] In an exemplary embodiment of the present disclosure, the distances from the bottom surface of the cushion block 23 and the tangent line of the outer wall of the sleeve 10 to the two side surfaces of the concave groove structure 211 are equal.

[0100] In an exemplary embodiment of the present disclosure, the sleeve 10 may be placed on the clamping structure body 21 first, and then the clamping structure body 21 may be fixed inside the heating device 30 through the connecting portion 22 , and finally the cushion block 23 may be pressed onto the sleeve 10 .

[0101] In step S540, a load spectrum is applied to the sleeve 10. The load spectrum describes the change of the load on the part. The load spectrum applied to the sleeve 10 can be a load spectrum generated according to theoretical calculations, or a load spectrum collected during the working process of the piston. The load spectrum can be applied to the sleeve 10 directly or indirectly through one or more fatigue testing machines. By applying the load spectrum and performing fatigue simulation on the piston, the fatigue life of the piston can be explored.

[0102] In an exemplary embodiment of the present disclosure, a channel 311 is formed on the top of the heating device 30, and the piston life test method further includes:

[0103] The pad 23 is connected to a fatigue simulation device through a channel 311;

[0104] The fatigue simulation device applies a load spectrum to the sleeve 10 through the spacer 23 .

[0105] The fatigue simulation device in this exemplary embodiment refers to a device that can provide a load spectrum, specifically, it can be a standard fatigue testing machine, or a dedicated piston fatigue testing machine, or other devices that can provide the required load spectrum such as a cylinder, cam, or push rod. The present disclosure does not make any special limitations on this.

[0106] The pad 23 can compress the sleeve 10 on one hand, and can also be connected to the fatigue simulation device as a load spectrum application device on the other hand, thus achieving two goals at one stroke and simplifying the test device.

[0107] In an exemplary embodiment of the present disclosure, the piston life test method may further include: obtaining the test environment temperature inside the heating device 30; identifying the test environment temperature, and sending a prompt signal when the test environment temperature does not meet the preset temperature range.

[0108] Specifically, it can be carried out through a temperature detection device 33, which can obtain and identify the ambient temperature and display it on a display screen arranged outside the heating device 30, or transmit the temperature signal to the main control terminal of the test device; when it is identified that the temperature does not meet the preset temperature range, an alarm arranged inside or outside the heating device 30 emits a prompt sound or a prompt light flashes, or the main control terminal of the test device displays an error prompt, so that the abnormal ambient temperature is manifested in time, which is convenient for adjusting the test process without having to regularly check the test temperature, thereby improving the efficiency and convenience of the test. At the same time, the abnormal temperature reminder also improves the safety of the test.

[0109] In an exemplary embodiment of the present disclosure, the test method for piston life may further include: when the test environment temperature reaches a threshold value, or when a test end command is received, turning off the heating device 30 and stopping applying the load spectrum to the sleeve 10. The test environment temperature threshold value may be a relatively high temperature value, and turning off the heating device 30 when the test environment temperature reaches the threshold value can avoid fire and other dangers; the test end command may be a shutdown signal from the master control terminal of the test device, such as a shutdown command; or it may be automatically issued according to preset conditions, such as automatically turning off the heating device 30 and stopping applying the load spectrum to the sleeve 10 when the duration of applying the load spectrum reaches a preset value, so that the test can be stopped in time when an abnormal situation occurs, thereby improving the safety of the test.

[0110] In an exemplary embodiment of the present disclosure, a piston life test method may be performed by a piston life test device provided by the present disclosure.

[0111] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. The present disclosure is intended to cover any variations, uses or adaptations of the present disclosure, which follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The description and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

[0112] It should be understood that the present disclosure is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from its scope. The scope of protection of the present disclosure is limited only by the appended claims.

Claims

1. A piston life test device, characterized in that: include: A heating device, comprising a housing and a heat source; A clamping device is arranged in the shell, the clamping device comprises a clamping structure body, a cushion block and a connecting part, the connecting part is arranged on both sides of the clamping structure body and connected to the shell, and the clamping structure body is fixed inside the heating device through the connecting part; The sleeve has the same design parameters as the piston, the design parameters include one or more parameters of the piston outer ring diameter, piston inner ring diameter, piston wall thickness, piston height, piston material, and piston processing technology. The sleeve is placed on the upper part of the clamping structure body, and the cushion block is pressed on the upper part of the sleeve; Wherein, the clamping structure body forms a concave groove structure, and both side surfaces of the concave groove structure are tangent to the outer side wall of the sleeve; the bottom surface of the cushion block is tangent to the outer wall of the sleeve.

2. The test device according to claim 1, characterized in that: The length of the cushion block is equal to the width of the clamping structure body, and the tangent line between the bottom surface of the cushion block and the outer wall of the sleeve is parallel to the axis of the sleeve.

3. The test device according to claim 1, characterized in that: The included angle between the two side surfaces of the concave groove structure is 90°-120°.

4. The test device according to claim 3, characterized in that: The angle between the two side surfaces of the concave groove structure is 120°, and the distances from the bottom surface of the cushion block and the tangent line of the outer wall of the sleeve to the two side surfaces of the concave groove structure are equal.

5. The test device according to claim 1, characterized in that: A channel is formed on the top of the heating device, and the pad is connected to a fatigue simulation device through the channel; The fatigue simulation device is used to apply a load spectrum to the sleeve through the pad.

6. A method for testing piston life, characterized in that: The test is conducted using the piston life test device according to any one of claims 1 to 5, wherein the test method comprises: Obtain design parameters of the piston; Obtaining the sleeve according to the design parameters; Heating the sleeve using the heating device; A load spectrum is applied to the sleeve.

7. The test method according to claim 6, characterized in that: The method further comprises: Obtaining the test environment temperature inside the heating device; Identifying the test environment temperature and sending a prompt signal when the test environment temperature does not meet a preset temperature range; When the test environment temperature reaches a threshold value, or when a test end command is received, the heating device is turned off and the application of the load spectrum to the sleeve is stopped.

8. The test method according to claim 6, characterized in that: The design parameters include: One or more parameters of the piston outer ring diameter, piston inner ring diameter, piston wall thickness, piston height, piston material, and piston processing technology; wherein the piston wall thickness is the minimum value of the piston skirt wall thickness.

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