Hydraulic ejector rod tension and compression fatigue clamp used in high-temperature environment
Through the design of hydraulic pin bar pulling fatigue fixtures, the use of high-temperature resistant materials and quick-plug joints can achieve stable clamping and cooling in high-temperature environments, solving the problems of thermal expansion and insufficient dimensional adaptability of fixtures in the prior art, and improving The accuracy and productivity of the test are carried out.
Patent Information
- Application Number
- CN202420010142.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-03
- Publication Date
- 2024-12-24
- Estimated Expiration
- 2034-01-03
AI Technical Summary
Existing high-temperature fatigue fixtures are heat-expanded under high temperature environments, resulting in unstable clamping, affecting the accuracy of test results, and are difficult to apply to threaded rod samples of different sizes.
A hydraulic pin bar tension fatigue fixture is designed, and the clamping parts are made of high-temperature resistant materials. The clamping of different sizes of threaded rod samples is achieved through hydraulic power clamping and quick plug joints, and the clamp is set inside the clamp. Annular cooling sink reduces expansion by cooling.
It realizes stable clamping of different sized thread rod samples under high temperature environment, eliminates thread gaps, reduces production costs, and reduces the expansion and deformation of the fixture due to high temperature through cooling water tanks, ensuring the normal operation of the device.
Smart Images
Figure CN222232181U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of mechanical clamps, in particular to a hydraulic push rod tension and compression fatigue clamp used in a high temperature environment. Background Art
[0002] With the continuous development and progress of modern industrial technology, some high-temperature alloys, ceramic composite materials, etc. are increasingly used in aerospace, marine ships, petrochemicals and other fields. It is particularly important to study their mechanical properties in high-temperature environments. Under the action of cyclic loads, materials will fail due to fatigue, and tensile and compressive fatigue is the most common fatigue form of high-temperature materials. Therefore, it is necessary to study the tensile and compressive fatigue properties of materials in high-temperature environments.
[0003] A high temperature fatigue fixture is a tool that can test the performance and durability of materials under high temperature environment, and is one of the indispensable equipment in high temperature fatigue test. For example, a high temperature low cycle fatigue test fixture disclosed in a Chinese patent with publication number CN219495944U records: "A high temperature low cycle fatigue test fixture, which relates to the technical field of fatigue test of metal materials, comprises a clamp body threaded sleeve, one end of which is threadedly connected to a manual hydraulic push rod built into the lower pull rod of an MTS fatigue tester, and is used to transmit the load and movement applied by the fatigue tester to the fatigue specimen; a rod-shaped specimen fixture cap, which is used to clamp a rod-shaped fatigue specimen; a plate-shaped specimen fixture assembly; the plate-shaped specimen fixture assembly is used to clamp a plate-shaped fatigue specimen; the rod-shaped specimen fixture cap and the plate-shaped specimen fixture assembly can be replaceably connected to the other end of the clamp body threaded sleeve. The present application has a simple structure and a small volume, and can be used for clamping high temperature fatigue bar specimens and plate specimens respectively through simple assembly."
[0004] The above technologies can all perform fatigue tests on materials at high temperatures, but in actual use, due to the thermal expansion of the fixture and unstable clamping in the high temperature environment, which greatly affects the accuracy of the test results. Therefore, it is urgent to find a fixture with stable clamping, reliable structure, and the ability to carry out tensile and compressive fatigue tests on threaded rod specimens of different sizes in a high temperature environment. For this purpose, a hydraulic push rod tensile and compressive fatigue fixture for high temperature environments is proposed. Utility Model Content
[0005] In view of the deficiencies in the prior art, the utility model provides a hydraulic push rod tension and compression fatigue clamp for use in high temperature environments, which solves the problem mentioned in the above background technology that in high temperature environments, the clamp expands due to heat, the clamping is unstable, and the accuracy of the test results is affected.
[0006] To achieve the above objectives, the utility model is implemented through the following technical solutions: a hydraulic push rod tension and compression fatigue clamp for high temperature environment, including a clamp body, the right side of the clamp body is fixedly connected to an end cover by a hexagon socket bolt, the inside of the clamp body is slidably connected to a piston, the right side of the piston is fixedly connected to a push rod by a hexagon socket bolt, the outer periphery of the push rod is slidably connected to a connecting rod, the inside of the connecting rod is threadedly connected to a nut, the inside of the nut is threadedly connected to a threaded rod sample, the top of the clamp body is threadedly connected to a straight joint A, and the top of the clamp body is threadedly connected to a straight joint B.
[0007] Preferably, the clamp body and the top of the end cover are both threadedly connected with a quick-insert connector E, the clamp body and the top of the end cover are both threadedly connected with a quick-insert connector F, and the clamp body and the right side of the end cover are both fixedly connected with a water tank sealing strip by welding.
[0008] Preferably, the right end face of the push rod is in contact with the left end face of the threaded rod sample, and the right end face of the push rod is not in contact with the left threaded end face of the nut.
[0009] Preferably, the right side of the clamp body and the left side of the end cover are sealed by an O-ring.
[0010] Preferably, the outer periphery of the piston is slidably connected to the inside of the end cover, and a guide ring, a standard shaft grid ring and a dust ring are arranged between the outer periphery of the piston and the inside of the end cover.
[0011] Preferably, the push rod, connecting rod and nut are all made of high temperature resistant material DZ.
[0012] Preferably, the connecting rod is provided with three evenly distributed observation holes with a diameter of eight millimeters, and the outer periphery of the connecting rod slides inside the end cover.
[0013] Preferably, the clamp body and the end cover are both provided with an annular cooling water groove with a height of 18 mm, the quick-plug connector E and the quick-plug connector F are respectively connected to the beginning and end of the annular cooling water groove, and the water groove sealing strip is arranged on the left side of the annular cooling water groove.
[0014] The utility model has the following beneficial effects:
[0015] 1. In the utility model, hydraulic power clamping is used, the clamping parts are made of high temperature resistant materials, and the size of the threaded hole is changed by replacing the nut, so that tension and compression fatigue tests can be carried out on threaded rod specimens of different sizes in a high temperature environment. At the same time, the push rod is not in contact with the nut, and the positive and negative thread gaps of the threaded rod specimens in the tension and compression tests are effectively eliminated, thereby expanding the use range of the fatigue clamp and reducing the production cost of the fatigue clamp.
[0016] 2. In the utility model, by providing quick-insert connectors E and F, cooling water flows through the annular cooling water groove inside the clamp body and the end cover, thereby cooling the clamp body and the end cover in a high-temperature working environment, reducing the expansion deformation of the clamp body and the end cover caused by high temperature, and ensuring the normal operation of the device. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 It is a cross-sectional view of a hydraulic push rod tension and compression fatigue clamp used in a high temperature environment when working;
[0018] Figure 2 The utility model is a three-dimensional structural schematic diagram of a hydraulic push rod tension and compression fatigue clamp for use in a high temperature environment.
[0019] Legend:
[0020] 1. Clamp body; 2. End cover; 3. Piston; 4. Push rod; 5. Connecting rod; 6. Nut; 7. Threaded rod specimen; 8. Sink sealing strip; 9. Straight connector A; 10. Straight connector B; 11. Quick connector E; 12. Quick connector F. DETAILED DESCRIPTION
[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0022] See also Figure 1-Figure 2The utility model provides a hydraulic push rod tension and compression fatigue fixture for high temperature environment, including a clamp body 1, the clamp body 1 is provided with two groups, symmetrically arranged on the left and right sides, the outer side of the clamp body 1 can be fixed on the electro-hydraulic servo fatigue testing machine through a threaded connection, the right side of the clamp body 1 is fixedly connected with an end cover 2 through a hexagon socket bolt, the right side of the clamp body 1 and the left side of the end cover 2 are sealed by an O-ring to ensure the sealing inside the clamp body 1 so that the oil will not leak, the inside of the clamp body 1 is slidably connected with a piston 3, the outer periphery of the piston 3 is slidably connected to the inside of the end cover 2, and when the clamp body 1 and the end cover 2 are in contact, a cylindrical The piston 3 slides in the cylindrical cavity. The piston 3 is respectively matched with the clamp body 1 and the end cover 2 by clearance, which compensates for various errors caused by high temperature, so that the piston 3 can slide smoothly. A guide ring, a standard shaft ring and a dust ring are respectively arranged between the outer periphery of the piston 3 and the inside of the end cover 2 to guide, seal and dustproof the piston 3. The right side of the piston 3 is fixedly connected with a push rod 4 by a hexagon socket bolt, and the outer periphery of the push rod 4 is slidably connected with a connecting rod 5. The push rod 4 and the connecting rod 5 are matched by clearance, so that the connecting rod 5 and the push rod 4 compensate for various errors caused by high temperature work, so that the push rod 4 and the connecting rod 5 can slide relatively smoothly. 5 is connected with a nut 6 through internal threads. By changing the size of the threaded hole through the nut 6, fatigue tests can be carried out on threaded rod specimens 7 of different sizes. The push rod 4, the connecting rod 5 and the nut 6 are all made of high temperature resistant material DZ22. DZ22 is a high strength medium carbon steel alloy tool steel with small deformation during heat treatment. DZ22 can be used to make tools that withstand large impact forces. The threaded rod specimen 7 is connected with the internal threads of the nut 6. The outer periphery of the connecting rod 5 slides inside the end cap 2. When installing the threaded rod specimen 7, the connecting rod 5 can be pushed inwards for easy installation. The right end face of the push rod 4 contacts the left end face of the threaded rod specimen 7. The connecting rod 5 is provided with There are three evenly distributed observation holes with a diameter of eight millimeters. Through the observation holes, it can be observed that the left end face of the threaded rod sample 7 can protrude from the left end face of the nut 6, ensuring that the push rod 4 can contact the left end face of the threaded rod sample 7 and does not contact the left threaded end face of the nut 6, and the right end face of the push rod 4 does not contact the left threaded end face of the nut 6. The top thread of the clamp body 1 is connected with a straight joint A9, and the top thread of the clamp body 1 is connected with a straight joint B10. The straight joint A9 and the straight joint B10 are connected to the internal cavity of the clamp body 1, and the oil enters the internal cavity of the clamp body 1 through the straight joint A9 and the straight joint B10, thereby causing the piston 3 to slide left and right.
[0023] See also Figure 1-Figure 2The top of the clamp body 1 and the end cover 2 are both threadedly connected with a quick-plug connector E11, and the top of the clamp body 1 and the end cover 2 are both threadedly connected with a quick-plug connector F12. The quick-plug connector E11 and the quick-plug connector F12 are conveniently connected to the cooling water pipe. The clamp body 1 and the end cover 2 are both provided with an annular cooling water trough with a height of 18 mm. The quick-plug connector E11 and the quick-plug connector F12 are respectively connected to the beginning and end of the annular cooling water trough. The cooling water flows into the cooling water trough from the quick-plug connector E11 on the clamp body 1 and the end cover 2 respectively, and flows out from the quick-plug connector F12 after a circle. The right side of the clamp body 1 and the end cover 2 are fixedly connected with a water trough sealing strip 8 by welding. The water trough sealing strip 8 is arranged on the left side on the right side of the annular cooling water trough, so that the annular cooling water trough has better sealing performance, so that the cooling water will not leak and affect the use of the device.
[0024] Working principle: When you want to perform a tension and compression fatigue test on the threaded rod sample 7, first select the nut 6 that matches the threaded rod sample 7, screw the nut 6 into the openings of the connecting rod 5 on the left and right sides, then push the connecting rods 5 on the left and right sides inward, and the connecting rods 5 slide inward along the inner wall of the end cover 2, and then screw the threaded rod sample 7 into the nuts 6 on both sides. The threaded rod sample 7 drives the nut 6 to rotate toward the center of the threaded rod sample 7, and the nut 6 drives the connecting rod 5 to slide outward on the inner wall of the end cover 2. After the threaded rod sample 7 is installed, observe the position of the internal threaded rod sample 7 through the observation window on the outer periphery of the connecting rod 5 to ensure that the threaded rod The left end face of the sample 7 protrudes from the left threaded end face of the nut 6, and the electro-hydraulic servo fatigue testing machine is started. At the same time, high temperature is applied to the threaded rod sample 7. The oil enters the internal cavity of the clamp body 1 from the straight-through joint A9, pushing the piston 3 and the push rod 4 to move in the direction of the threaded rod sample 7 until the push rod 4 presses the threaded rod sample 7 tightly. By controlling the pressure of the oil, different pressures are applied to the threaded rod sample 7, so that the tension and compression fatigue test of the threaded rod sample 7 under high temperature is carried out. At the same time, the push rod 4 only applies pressure to the threaded rod sample 7 and does not contact the nut 6, ensuring the stability of the nut 6 clamping the threaded rod sample 7. At the same time, in order to avoid abnormal operation of the clamp body 1 and the end cover 2 due to high temperature, when testing the threaded rod sample 7, cooling water flows into the cooling water tank from the quick-insert joints E11 on the clamp body 1 and the end cover 2 respectively, and flows out from the quick-insert joint F12 after one cycle, so as to cool the clamp body 1 and the end cover 2, ensuring that the clamp body 1 and the end cover 2 will not expand due to high temperature, and the gap will not expand, so as to ensure the normal operation of the device.
[0025] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A hydraulic jack tension and compression fatigue clamp for use in a high temperature environment, comprising a clamp body (1), characterized in that: The right side of the clamp body (1) is fixedly connected to an end cover (2) via a hexagon socket bolt, the clamp body (1) is internally slidably connected to a piston (3), the right side of the piston (3) is fixedly connected to a push rod (4) via a hexagon socket bolt, the outer periphery of the push rod (4) is slidably connected to a connecting rod (5), the connecting rod (5) is internally threadedly connected to a nut (6), the nut (6) is internally threadedly connected to a threaded rod sample (7), the top of the clamp body (1) is threadedly connected to a straight joint A (9), and the top of the clamp body (1) is threadedly connected to a straight joint B (10).
2. The hydraulic jack tension and compression fatigue fixture for high temperature environment according to claim 1, characterized in that: The tops of the clamp body (1) and the end cover (2) are both threadedly connected with a quick-insertion connector E (11), the tops of the clamp body (1) and the end cover (2) are both threadedly connected with a quick-insertion connector F (12), and the right sides of the clamp body (1) and the end cover (2) are both fixedly connected with a water tank sealing strip (8) by welding.
3. The hydraulic jack tension and compression fatigue fixture for high temperature environment according to claim 1, characterized in that: The right end face of the push rod (4) contacts the left end face of the threaded rod sample (7), and the right end face of the push rod (4) does not contact the left threaded end face of the nut (6).
4. The hydraulic jack tension and compression fatigue fixture for high temperature environment according to claim 1, characterized in that: The right side of the clamp body (1) and the left side of the end cover (2) are sealed via an O-ring.
5. The hydraulic jack tension and compression fatigue fixture for high temperature environment according to claim 1, characterized in that: The outer periphery of the piston (3) is slidably connected to the interior of the end cover (2), and a guide ring, a standard shaft-use grid ring and a dust ring are arranged between the outer periphery of the piston (3) and the interior of the end cover (2).
6. The hydraulic jack tension and compression fatigue fixture for high temperature environment according to claim 1, characterized in that: The push rod (4), connecting rod (5) and nut (6) are all made of high temperature resistant material DZ22.
7. The hydraulic jack tension and compression fatigue fixture for high temperature environment according to claim 1, characterized in that: The connecting rod (5) is provided with three evenly distributed observation holes with a diameter of eight millimeters, and the outer periphery of the connecting rod (5) slides inside the end cover (2).
8. The hydraulic jack tension and compression fatigue fixture for high temperature environment according to claim 2, characterized in that: The clamp body (1) and the end cover (2) are both provided with an annular cooling water groove with a height of 18 mm. The quick-connect connector E (11) and the quick-connect connector F (12) are respectively connected to the beginning and end of the annular cooling water groove. The water groove sealing strip (8) is arranged on the left side of the annular cooling water groove.