Engine cylinder liner mechanical fatigue testing device and method

Abstract

The application provides an engine cylinder liner mechanical fatigue testing device and method, which comprises a positioning column, a cylinder liner to be tested is installed on the outer side of the positioning column; a cover plate is installed in cooperation with the positioning column, the cover plate closes the upper end opening of the cylinder liner to be tested, and a pressurizing cavity is formed between the cover plate, the positioning column and the cylinder liner to be tested; and a tension and compression assembly is used to apply pressure or tension to the side wall of the cylinder liner to be tested. The application has the beneficial effects that the hydraulic oil in the pressurizing cavity and the tension and compression assembly have the same frequency, and the phase difference of the two channels is 0, the side thrust of the piston when exploding is simulated, the side thrust of the piston when reversing is simulated, the structural strength and fatigue reliability of the cylinder liner can be comprehensively evaluated, and the testing accuracy is improved.

Description

Technical Field

[0001] This invention belongs to the field of cylinder liner mechanical fatigue testing technology, and in particular relates to an engine cylinder liner mechanical fatigue testing device and method. Background Technology

[0002] As a component of the engine combustion chamber, the cylinder liner is subjected to cyclical effects of high temperature and high pressure during operation, making its structural strength and fatigue reliability crucial. In particular, the shoulder area of ​​the cylinder liner may fracture due to various factors such as overload, overspeed, and insufficient rigidity. In the early stages of mass production, fatigue reliability tests of components based on component test benches are essential for product development.

[0003] Existing cylinder liner mechanical fatigue testing equipment is mainly based on hydraulic servo fatigue testing systems, which use hydraulic oil to simulate the force of gas on the cylinder liner. However, as engine speed and combustion pressure increase, piston side thrust increases, causing the cylinder liner shoulder to break. Traditional testing methods only consider the combustion pressure and fail to take into account the force of the piston on the cylinder liner during combustion and reversal, resulting in deviations in test results. Summary of the Invention

[0004] In view of this, the present invention aims to provide an engine cylinder liner mechanical fatigue testing device and method, in order to solve at least one of the above-mentioned technical problems.

[0005] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0006] This invention provides an engine cylinder liner mechanical fatigue testing device, comprising:

[0007] The locating post is used to mount the cylinder liner to be tested on the outside of the locating post.

[0008] A cover plate is installed in conjunction with a positioning post. The cover plate closes the upper opening of the cylinder liner to be tested, and a pressurization chamber is formed between the cover plate, the positioning post, and the cylinder liner to be tested.

[0009] A tension-compression assembly, used to apply a thrust or tension force to the sidewall of the cylinder liner to be tested.

[0010] Furthermore, the fatigue testing device also includes a base, the positioning column is installed in conjunction with the base, a housing is fixed on the base, and the cover plate is detachably connected to the housing by bolts.

[0011] Furthermore, the upper end of the housing has a positioning groove that matches the positioning ring on the upper end of the cylinder liner to be tested, and the positioning ring is installed inside the positioning groove.

[0012] Furthermore, the lower end of the positioning column is hinged to the mounting base via a hinge shaft, and the mounting base is fixedly connected to the base.

[0013] Furthermore, a sealing gasket is provided between the cover plate and the upper end face of the cylinder liner to be tested;

[0014] A sealing ring is provided between the outer wall of the positioning post and the inner wall of the cylinder liner to be tested.

[0015] Furthermore, a through groove corresponding to the output shaft of the tension-compression assembly is formed on the side wall of the housing. The output shaft of the tension-compression assembly is connected to a connecting ring by bolts, and the connecting ring is connected to the test cylinder liner.

[0016] The position of the connecting ring corresponds to the position of the hinge shaft.

[0017] Furthermore, the cover plate has a connection hole that communicates with the pressurization chamber, and the connection hole is connected to the liquid outlet end of the pressurization device.

[0018] Another aspect of the present invention provides a method for using the engine cylinder liner mechanical fatigue testing device described in one aspect, comprising the following steps:

[0019] S1. When the pressure of the hydraulic oil in the pressurization chamber reaches the first standard pressure, the tension-compression assembly applies a thrust to the cylinder liner to be tested.

[0020] S2. When the pressure of the hydraulic oil in the pressurization chamber reaches the second standard pressure, the tension-compression assembly applies a push-pull force to the cylinder liner to be tested.

[0021] S3. Repeat steps S1-S2 as a test loop;

[0022] If the number of cycles does not reach the specified value and the cylinder liner under test is damaged, it is deemed unqualified, and the number of cycles is recorded.

[0023] If the number of test cycles reaches the specified value, the condition of the cylinder liner under test is checked. If the cylinder liner under test is in good condition, it is judged as qualified; if the cylinder liner under test is damaged, it is judged as unqualified.

[0024] Furthermore, in step S1, the first standard pressure is the pressure inside the cylinder liner when the piston explodes under the actual use state of the cylinder liner under test, and the thrust applied to the cylinder liner under test by the tension-compression assembly is the maximum lateral force of the piston.

[0025] In step S2, the second standard pressure is the pressure inside the cylinder liner when the piston reverses direction under the actual use state of the cylinder liner under test, and the tension force applied to the cylinder liner under test by the tension assembly is the tension force when the piston reverses direction.

[0026] Furthermore, the pressure of the hydraulic oil in the pressurization chamber varies in pulses, and these pulse variations are the same as the pressure variations on the inner side of the cylinder liner under test during actual use.

[0027] Compared with the prior art, the engine cylinder liner mechanical fatigue testing device and method of the present invention have the following advantages:

[0028] (1) The mechanical fatigue testing device for engine cylinder liners described in this invention has hydraulic oil in the pressurized chamber and tension and compression groups at the same frequency, and the phase difference between the two channels is 0. It simulates the lateral thrust on the cylinder liner when the piston explodes and the lateral thrust on the cylinder liner when the piston reverses direction. It can comprehensively evaluate the structural strength and fatigue reliability of the cylinder liner and improve the accuracy of the test. Attached Figure Description

[0029] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0030] Figure 1 This is a schematic cross-sectional view of the device described in an embodiment of the present invention.

[0031] Explanation of reference numerals in the attached figures:

[0032] 1. Housing; 2. Cover plate; 3. Base; 4. Cylinder liner to be tested; 5. Sealing gasket; 6. Sealing ring; 7. Tension / compression assembly; 8. Positioning post; 9. Mounting base; 10. Bolt. Detailed Implementation

[0033] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0034] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0035] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0036] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0037] like Figure 1 As shown, an engine cylinder liner mechanical fatigue testing device includes:

[0038] Positioning post 8, the cylinder liner 4 to be tested is installed on the outside of positioning post 8;

[0039] Cover plate 2 is installed in conjunction with positioning post 8. Cover plate 2 closes the upper opening of the cylinder liner 4 to be tested, and a pressurization chamber is formed between cover plate 2, positioning post 8 and cylinder liner 4 to be tested.

[0040] The tension-compression assembly 7 is used to apply thrust or tension to the sidewall of the cylinder liner 4 to be tested.

[0041] In some embodiments, the tension / compression assembly 7 employs an existing electric cylinder, while in other embodiments, it employs an existing tension / compression testing system.

[0042] The fatigue testing device also includes a base 3, a positioning column 8 which is installed in conjunction with the base 3, a housing 1 which is fixed on the base 3, and a cover plate 2 which is detachably connected to the housing 1 by bolts 10.

[0043] The upper end of the housing 1 has a positioning groove that matches the positioning ring on the upper end of the cylinder liner 4 to be tested. The positioning ring is installed inside the positioning groove. The positioning groove positions the positioning ring to prevent the cylinder liner 4 to be tested from shaking.

[0044] The lower end of the positioning post 8 is hinged to the mounting base 9 via a hinge shaft. When the tension and compression assembly 7 applies a pushing force and a pulling force, the positioning post 8 can rotate along the position of the hinge shaft, which facilitates the application of the pushing and pulling force by the tension and compression assembly 7. The mounting base 9 is fixedly connected to the base 3.

[0045] A sealing gasket 5 is provided between the cover plate 2 and the upper end face of the cylinder liner 4 to be tested; the sealing gasket 5 improves the sealing performance between the cover plate 2 and the cylinder liner 4 to be tested.

[0046] A sealing ring 6 is provided between the outer wall of the positioning post 8 and the inner wall of the cylinder liner 4 under test. The sealing ring 6 improves the sealing performance between the outer wall of the positioning post 8 and the inner wall of the cylinder liner 4 under test. In addition, the sealing ring 6 has a certain degree of elasticity, which ensures the sealing performance while also providing a certain deformation space for the cylinder liner 4 under test, so as to facilitate the application of thrust and tension by the tension-compression assembly 7.

[0047] The housing 1 has a through hole on its side wall corresponding to the output shaft of the tension-compression assembly 7. The housing of the tension-compression assembly 7 is fixedly connected to the housing 1. The output shaft of the tension-compression assembly 7 is connected to the connecting ring by bolts. The connecting ring is connected to the test cylinder liner 4.

[0048] The position of the connecting ring corresponds to the position of the hinge shaft.

[0049] The cover plate 2 has a connection hole that communicates with the pressurization chamber and is connected to the liquid outlet of the pressurization equipment.

[0050] The pressurization equipment can use existing servo hydraulic cylinders.

[0051] A method for testing the mechanical fatigue of an engine cylinder liner includes the following steps:

[0052] S1. When the pressure of the hydraulic oil in the pressurization chamber reaches the first standard pressure, the tension-compression assembly 7 applies a thrust to the cylinder liner 4 to be tested.

[0053] S2. When the pressure of the hydraulic oil in the pressurization chamber reaches the second standard pressure, the tension-compression assembly 7 applies a tension force to the cylinder liner 4 to be tested.

[0054] S3. Repeat steps S1-S2 as a test loop;

[0055] If the number of cycles does not reach the specified value and the cylinder liner 4 under test is damaged, it is deemed unqualified, and the number of cycles is recorded.

[0056] If the number of test cycles reaches the specified value, the condition of the cylinder liner 4 under test is checked. If the cylinder liner 4 under test is in good condition, it is judged as qualified; if the cylinder liner 4 under test is damaged, it is judged as unqualified.

[0057] In step S1, the first standard pressure is the pressure inside the cylinder liner 4 when the piston explodes under actual use conditions; the thrust applied by the tension-compression assembly 7 to the cylinder liner 4 under test is the maximum lateral force of the piston.

[0058] In step S2, the second standard pressure is the pressure inside the cylinder liner 4 when the piston reverses under actual use conditions, and the tensioning component 7 applies the tension to the cylinder liner 4 when the piston reverses.

[0059] The pressure of the hydraulic oil in the pressurization chamber changes in pulses, and these pulse changes are the same as the pressure changes on the inner side of the cylinder liner 4 under test in actual use.

[0060] In the pressurized chamber, the hydraulic oil and the tensioning group operate at the same frequency, and the phase difference between the two channels is 0. This simulates the lateral thrust on the cylinder liner when the piston explodes and the lateral thrust on the cylinder liner when the piston reverses direction. This allows for a comprehensive evaluation of the cylinder liner's structural strength and fatigue reliability, thus improving the accuracy of the test.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A mechanical fatigue testing device for engine cylinder liners, characterized in that, include: The positioning post (8) is used to install the cylinder liner (4) to be tested on the outside of the positioning post (8); Cover plate (2), the cover plate (2) is installed in conjunction with the positioning post (8), the cover plate (2) closes the upper opening of the cylinder liner (4) to be tested, and a pressurized chamber is formed between the cover plate (2), the positioning post (8) and the cylinder liner (4) to be tested; The tension-compression assembly (7) is used to apply a thrust or a pull force to the sidewall of the cylinder liner (4) to be tested; The fatigue testing device also includes a base (3), the positioning column (8) is installed in conjunction with the base (3), the housing (1) is fixed on the base (3), and the cover plate (2) is detachably connected to the housing (1) by bolts (10); The lower end of the positioning column (8) is hinged to the mounting base (9) via a hinge shaft, and the mounting base (9) is fixedly connected to the base (3); The housing (1) has a through groove on its side wall corresponding to the output shaft of the tension-compression assembly (7). The output shaft of the tension-compression assembly (7) is connected to the connecting ring by bolts. The connecting ring is connected to the test cylinder liner (4). The position of the connecting ring corresponds to the position of the hinge shaft.

2. The engine cylinder liner mechanical fatigue testing device according to claim 1, characterized in that: The upper end of the housing (1) has a positioning groove that matches the positioning ring on the upper end of the cylinder liner (4) to be tested, and the positioning ring is installed inside the positioning groove.

3. The engine cylinder liner mechanical fatigue testing device according to claim 1, characterized in that: A sealing gasket (5) is provided between the cover plate (2) and the upper end face of the cylinder liner (4) to be tested; A sealing ring (6) is provided between the outer wall of the positioning column (8) and the inner wall of the cylinder liner (4) to be tested.

4. The engine cylinder liner mechanical fatigue testing device according to claim 1, characterized in that: The cover plate (2) has a connection hole that communicates with the pressurization chamber and the connection hole is connected to the liquid outlet end of the pressurization device.

5. A method for using the engine cylinder liner mechanical fatigue testing device according to any one of claims 1-4, characterized in that: Includes the following steps: S1. When the pressure of the hydraulic oil in the pressurization chamber reaches the first standard pressure, the tension-compression assembly (7) applies a thrust to the cylinder liner (4) to be tested. S2. When the pressure of the hydraulic oil in the pressurization chamber reaches the second standard pressure, the tension-compression assembly (7) applies a tension force to the cylinder liner (4) to be tested. S3. Repeat steps S1-S2 as a test loop; If the number of cycles does not reach the specified value and the cylinder liner (4) to be tested is damaged, it is judged as unqualified and the number of cycles is recorded; If the number of test cycles reaches the specified value, the condition of the cylinder liner (4) to be tested is checked. If the condition of the cylinder liner (4) to be tested is good, it is judged as qualified. If the condition of the cylinder liner (4) to be tested is damaged, it is judged as unqualified.

6. The method according to claim 5, characterized in that: In step S1, the first standard pressure is the pressure inside the cylinder liner when the piston explodes under actual use conditions of the cylinder liner (4) to be tested, and the thrust applied by the tensioning assembly (7) to the cylinder liner (4) to be tested is the maximum lateral force of the piston. In step S2, the second standard pressure is the pressure inside the cylinder liner when the piston reverses under the actual use state of the cylinder liner (4) to be tested, and the tension force applied by the tension assembly (7) to the cylinder liner (4) to be tested is the tension force when the piston reverses.

7. The method according to claim 5, characterized in that: The pressure of the hydraulic oil in the pressurization chamber changes in pulses, and the pulse changes are the same as the pressure changes on the inner side of the cylinder liner (4) under test in actual use.

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