Piston pin hole mechanical fatigue test device

Abstract

The invention provides a piston pin hole mechanical fatigue test device, which comprises a loading head, a simulation cylinder sleeve, a piston, a temperature control system, a piston support and a support base, and is characterized in that the loading head is connected with a tension and compression testing machine through a cooling transfer disc, and high temperature resistant silicone oil is filled between the top of the piston and the loading head; the pressure load of the testing machine pressurizes the high-temperature-resistant silicone oil through the loading head so as to simulate the working pressure of the piston during working, and the temperature control system is arranged outside the simulation cylinder sleeve and is used for applying a piston temperature field; the piston is installed on the piston support through a piston pin, the piston support is fixedly connected with the supporting base, the piston is arranged in the simulation cylinder sleeve, and an inner cavity of the piston is filled with high-temperature-resistant silicone oil and used for simulating the lubricating condition of the piston. According to the application, a load is applied to the test piston in a manner of pressurizing the high-temperature-resistant silicone oil by adopting the tension and compression testing machine, the test piston is heated to simulate a high-temperature environment, and the device can be used for carrying out a high-temperature mechanical fatigue test on the piston pin hole.

Description

Technical Field

[0001] This application belongs to the technical field of engine piston testing, and particularly relates to a mechanical fatigue test device for piston pin holes. Background Technique

[0002] The piston is a key moving component in the engine, and together with the cylinder, cylinder head, etc., it forms a closed combustion chamber space. The piston is subjected to the periodic action of the gas force in the cylinder, the reciprocating inertia force generated by the high-speed reciprocating mass, and the side thrust generated when the connecting rod is inclined. Moreover, the piston works at a high temperature for a long time. The high temperature reduces the strength of the piston material and also causes thermal deformation and thermal stress of the piston. The piston pin hole is the most vulnerable part of the piston, and ensuring the structural reliability of the piston pin hole is the key to engine design.

[0003] Currently, a fatigue test system is generally used to simulate the load borne by the piston to evaluate the fatigue performance of the piston pin hole. The test device generally uses hydraulic equipment. This device can simulate the action of explosion pressure and inertia force at the same time, but the test frequency is low and the test cost is high. Most importantly, due to the characteristics of the test loading medium, it is impossible to simulate the temperature field of the piston. Summary of the Invention

[0004] In view of this, this application aims to propose a mechanical fatigue test device for piston pin holes to solve at least one of the above problems.

[0005] To achieve the above object, the technical solution of this application is realized as follows:

[0006] This application provides a mechanical fatigue test device for piston pin holes, including a loading head, a simulated cylinder liner, a piston, a temperature control system, a piston support, and a support base. Among them, the loading head is connected to a tensile-compressive testing machine through a cooling adapter plate. High-temperature resistant silicone oil is filled between the top of the piston and the loading head. The pressure load of the testing machine pressurizes the high-temperature resistant silicone oil through the loading head to simulate the working pressure during the piston operation. The temperature control system is arranged outside the simulated cylinder liner, and the temperature control system is used to apply the piston temperature field;

[0007] The piston is installed on the piston support through a piston pin. The piston support is fixedly connected to the support base. The piston is placed inside the simulated cylinder liner, and the inner cavity of the piston is filled with high-temperature resistant silicone oil to simulate the lubrication condition of the piston.

[0008] Further, a gap is reserved between the top end face of the piston and the bottom end face of the loading head to form an oil cavity for filling high-temperature resistant silicone oil.

[0009] Further, the loading head has a stepped cylinder structure, and oil channels are symmetrically arranged on both sides of it. Among them, one side is used for filling oil into the oil cavity, and the other side is used for installing a pressure sensor to monitor the test load.

[0010] A cooling oil circuit runs through the cooling adapter plate, and a first heat insulation gasket is provided between the loading head and the cooling adapter plate.

[0011] Further, the simulation cylinder liner has a hollow cylinder structure inside, and a plurality of first rubber ring grooves are arranged around its inner wall. First high-temperature resistant sealing rings are installed in the first rubber ring grooves, and the first high-temperature resistant sealing rings are respectively attached to the mating surfaces of the loading head and the piston.

[0012] Further, the support base has a cylinder structure, and a protrusion for positioning the piston support is provided at the central position. The piston support is fixed on the support base through fasteners;

[0013] An annular slot is also provided on the support base, the bottom of the piston is correspondingly inserted into the slot, and a second rubber ring groove is also provided on the outer circle of the support base around the annular slot. A second high-temperature resistant sealing ring is installed in the second rubber ring groove;

[0014] The support base, the piston, the simulation cylinder liner and the second high-temperature resistant sealing ring form a sealed oil cavity for filling high-temperature resistant silicone oil, which is used for lubrication at the piston pin hole.

[0015] Further, a temperature measuring hole is also provided on the support base, the temperature measuring hole is used for installing a thermocouple, the thermocouple extends into the sealed oil cavity, and the thermocouple is connected to the temperature control system.

[0016] Further, an oil inlet communicating with the sealed oil cavity is provided on one side of the support base.

[0017] Further, a second heat insulation gasket is also provided at the bottom of the support base.

[0018] Compared with the prior art, the piston pin hole mechanical fatigue test device of the present application has the following beneficial effects:

[0019] The piston pin hole mechanical fatigue test device of the present application applies a load to the test piston by pressurizing high-temperature resistant silicone oil with a tensile and compressive testing machine, and heats the test piston to simulate a high-temperature environment. This device can conduct high-temperature mechanical fatigue tests on piston pin holes. Description of the Drawings

[0020] The accompanying drawings, which form a part of this application, are used to provide a further understanding of this application. The schematic embodiments and their descriptions of this application are used to explain this application and do not constitute an improper limitation to this application. In the drawings:

[0021] Figure 1 It is a plan sectional view of a piston pin hole mechanical fatigue test device according to an embodiment of this application;

[0022] Figure 2 It is an exploded view of the structure of a piston pin hole mechanical fatigue test device according to an embodiment of this application.

[0023] Description of reference numerals:

[0024] 1 - Cooling adapter plate; 2 - Loading head; 3 - Simulated cylinder liner; 4 - Piston; 5 - Temperature control system; 6 - High-temperature silicone oil; 7 - Piston support; 8 - Support base; 9 - First heat insulation gasket; 10 - First high-temperature sealing ring; 11 - Piston pin; 12 - Thermocouple; 13 - Second high-temperature sealing ring; 14 - Second heat insulation gasket. Detailed implementation manners

[0025] To make the objectives, technical solutions, and advantages of this application clearer and more understandable, the following further elaborates on this application in combination with specific embodiments and with reference to the accompanying drawings.

[0026] It should be noted that unless otherwise defined, the technical terms or scientific terms used in the embodiments of this application should have the ordinary meanings understood by those with ordinary skills in the field to which this application belongs. The "first", "second", and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are only used to distinguish different components. Words such as "including" or "comprising" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. Words such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Upper", "lower", "left", "right", etc. are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0027] Please refer to Figure 1 and Figure 2As shown in the figure, this embodiment provides a mechanical fatigue test device for piston pin holes, which includes a loading head, a simulated cylinder liner, a piston, a temperature control system, a piston support, and a support base. Among them, the loading head is connected to a tensile and compressive testing machine through a cooling adapter plate. High-temperature resistant silicone oil is filled between the top of the piston and the loading head. The pressure load of the testing machine pressurizes the high-temperature resistant silicone oil through the loading head to simulate the working pressure during the piston operation. The temperature control system is arranged outside the simulated cylinder liner and is used to apply the piston temperature field;

[0028] The piston is installed on the piston support through a piston pin. The piston support is fixedly connected to the support base. The piston is placed inside the simulated cylinder liner, and high-temperature resistant silicone oil is filled in the inner cavity of the piston to simulate the lubrication condition of the piston.

[0029] Specifically, in this embodiment, the piston is installed on the piston support through a piston pin, and forms a closed cavity with the simulated cylinder liner, the loading head, and the sealing ring. High-temperature resistant silicone oil is between the top of the piston and the loading head. The temperature control system is arranged outside the simulated cylinder liner. The pressure load of the testing machine pressurizes the high-temperature resistant silicone oil through the loading head to complete the force transmission, and the piston temperature field is applied through the temperature control system.

[0030] This application applies the load to the piston by the method of mechanical load transmission through silicone oil, solves the problem that the existing hydraulic test device directly loads the piston top, and cannot apply the temperature field to the piston due to medium problems. At the same time, it solves the problem of local stress on the piston top caused by using other solid media.

[0031] This device can apply mechanical load and temperature field to the piston at the same time, and can simulate the influence of temperature on materials. Under the condition that the temperature field can be applied, the test load is applied on the piston top through high-temperature resistant silicone oil. The gap between the test and the actual working state is small, the component test simulation degree is high, and the test result is more accurate.

[0032] A mechanical fatigue test device for piston pin holes described in this embodiment applies the load to the test piston by pressurizing the high-temperature resistant silicone oil with a tensile and compressive testing machine, and heats the test piston to simulate a high-temperature environment. This device can conduct high-temperature mechanical fatigue tests on piston pin holes.

[0033] In some embodiments, the loading head has a stepped cylindrical structure. The provided stepped structure serves as a mechanical limit, so that when the loading head descends to the lowest point, it maintains a certain distance from the piston to prevent the piston from being damaged due to abnormal load. Oil channels are symmetrically arranged on both sides of the loading head. Among them, one side is used for filling oil into the oil cavity (a gap is reserved between the piston and the loading head to form an oil cavity for filling high-temperature resistant silicone oil), and the other side is used for installing a pressure sensor to monitor the test load;

[0034] A cooling oil passage runs through the cooling adapter plate, and a first heat insulation gasket is provided between the loading head and the cooling adapter plate.

[0035] Specifically, in this embodiment, the test device is connected to a tensile-compressive testing machine through bolts, applying a specified pressure load to the piston to simulate the action of the gas force in the cylinder and to evaluate the structural strength of the piston pin hole. In addition, this test device is applicable to various tensile-compressive fatigue testing machines, and the cooling adapter plate is designed according to the interface of the testing machine, with strong versatility.

[0036] In some embodiments, the simulated cylinder liner is a hollow cylindrical structure with a plurality of circumferentially arranged first rubber ring grooves formed on its inner wall. A first high-temperature resistant sealing ring is installed in the first rubber ring grooves, and the first high-temperature resistant sealing rings are respectively attached to the mating surfaces of the loading head and the piston.

[0037] Specifically, in this embodiment, the simulated cylinder liner is a hollow cylindrical structure. The loading head is correspondingly arranged above the simulated cylinder liner. A piston is installed inside the simulated cylinder liner and sealed by a high-temperature resistant sealing ring. The loading head, the simulated cylinder liner, the sealing ring, and the piston together form a pressure oil storage cavity. Pressure is applied to the oil cavity through the loading head, thereby transmitting the test load to the piston.

[0038] In some embodiments, the support base is a cylindrical structure, and a protrusion for positioning the piston support is provided at the central position. The piston support is fixed to the support base through fasteners;

[0039] An annular slot is also formed on the support base, and the bottom of the piston is correspondingly inserted into the slot. A second rubber ring groove is also formed on the outer ring of the support base around the annular slot, and a second high-temperature resistant sealing ring is installed in the second rubber ring groove;

[0040] The support base, the piston, the simulated cylinder liner, and the second high-temperature resistant sealing ring form a closed oil cavity for filling high-temperature resistant silicone oil, which is used for lubrication at the piston pin hole;

[0041] A temperature measuring hole is also provided on the support base, and the temperature measuring hole is used for installing a thermocouple. The thermocouple extends into the closed oil cavity, and the thermocouple is connected to a temperature control system;

[0042] An oil inlet communicating with the sealed oil cavity is provided on one side of the support base.

[0043] Specifically, in this embodiment, the structure of the support base is a cylinder, on which there are rubber ring grooves, an oil inlet, and a temperature measuring hole. The support base, the piston, the simulated cylinder liner, and the rubber ring form a closed oil cavity for lubrication at the piston pin hole. The temperature measuring hole is used for installing a thermocouple, and the thermocouple is located near the pin hole on the inner wall of the piston. The thermocouple is connected to the temperature control system. The temperature control system body is a hollow cylindrical structure and is installed on the outer wall of the simulated cylinder liner. The temperature control system can set the temperature and perform closed-loop control through the feedback signal of the thermocouple to achieve the control of the piston temperature field.

[0044] In some embodiments, a second heat insulation gasket is further provided at the bottom of the support base.

[0045] Specifically, in this embodiment, to avoid the temperature rise of the testing machine, heat insulation gaskets are respectively arranged on the upper side of the loading head and the lower side of the support base, and the cooling adapter plate is cooled by an oil circuit circulation.

[0046] Embodiment 1

[0047] The piston test piece is installed on the support base through a piston pin, and the piston is placed in the simulated cylinder liner. The inner cavity of the piston is filled with high-temperature resistant silicone oil to simulate the lubrication condition of the piston. The simulated cylinder liner, piston, and loading head form a closed cavity, and the cavity is filled with high-temperature resistant silicone oil as the test loading medium. The loading head is installed on the tensile and compressive testing machine through bolts and transmits pressure through the high-temperature resistant silicone oil to simulate the explosion pressure during the operation of the piston. A temperature control system is provided on the outer wall of the simulated cylinder liner, and the temperature control system collects the feedback of the thermocouple to simulate the temperature during the operation of the piston. The heat insulation gaskets are used for heat insulation between the test device and the test equipment, and the cooling adapter plate protects the test equipment through oil circuit cooling.

[0048] The test device is connected to the tensile and compressive testing machine through bolts to apply a specified pressure load to the piston, which is used to simulate the action of the gas force in the cylinder and to evaluate the structural strength of the piston pin hole.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features. And these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered by the scope of the claims and the description of the present invention.

[0050] The embodiments of the present application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the embodiments of the present application shall be included within the protection scope of the present application.

Claims

1. A mechanical fatigue test device for piston pin holes, characterized in that: It includes a loading head, a simulated cylinder liner, a piston, a temperature control system, a piston support and a support base. Among them, the loading head is connected to a tensile and compressive testing machine through a cooling adapter plate. High-temperature resistant silicone oil is filled between the top of the piston and the loading head. The pressure load of the testing machine pressurizes the high-temperature resistant silicone oil through the loading head to simulate the working pressure during the operation of the piston. The temperature control system is arranged outside the simulated cylinder liner, and the temperature control system is used to apply the piston temperature field; The piston is installed on the piston support through a piston pin. The piston support is fixedly connected to the support base. The piston is placed inside the simulated cylinder liner, and high-temperature resistant silicone oil is filled in the inner cavity of the piston to simulate the lubrication conditions of the piston.

2. The mechanical fatigue test device for piston pin holes according to claim 1, characterized in that: A gap is reserved between the top end face of the piston and the bottom end face of the loading head to form an oil cavity for filling high-temperature resistant silicone oil.

3. The mechanical fatigue test device for piston pin holes according to claim 2, characterized in that: The loading head has a stepped cylindrical structure, and oil channels are symmetrically arranged on both sides of it. Among them, one side is used for filling oil into the oil cavity, and the other side is used for installing a pressure sensor to monitor the test load; A cooling oil circuit runs through the cooling adapter plate, and a first heat insulation gasket is provided between the loading head and the cooling adapter plate.

4. The mechanical fatigue test device for piston pin holes according to claim 1, characterized in that: The simulated cylinder liner is a hollow cylindrical structure inside, and a plurality of circumferentially arranged first rubber ring grooves are provided on its inner wall. First high-temperature resistant sealing rings are installed in the first rubber ring grooves, and the first high-temperature resistant sealing rings are respectively attached to the mating surfaces of the loading head and the piston.

5. The mechanical fatigue test device for piston pin holes according to claim 1, characterized in that: The support base is a cylindrical structure, and a protrusion for positioning the piston support is provided at the central position. The piston support is fixed on the support through fasteners; A circular slot is also provided on the support base, and the bottom of the piston is correspondingly inserted into the slot. A second rubber ring groove is also provided on the outer circle of the support base around the circular slot, and a second high-temperature resistant sealing ring is installed in the second rubber ring groove; The support base, the piston, the simulated cylinder liner and the second high-temperature resistant sealing ring form a sealed oil cavity for filling high-temperature resistant silicone oil, which is used for lubrication at the piston pin hole.

6. The mechanical fatigue test device for piston pin holes according to claim 5, characterized in that: A temperature measuring hole is also provided on the support base, and the temperature measuring hole is used for installing a thermocouple. The thermocouple extends into the sealed oil cavity, and the thermocouple is connected to the temperature control system.

7. The mechanical fatigue test device for piston pin holes according to claim 5, characterized in that: An oil inlet communicating with the sealed oil cavity is provided on one side of the support base.

8. The mechanical fatigue test device for piston pin holes according to claim 1, characterized in that: A second heat insulation gasket is further arranged at the bottom of the support base.

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