Small-diameter thin-wall molybdenum or molybdenum alloy pipe clamp

Abstract

A small-diameter thin-wall molybdenum or molybdenum alloy pipe clamp comprises two clamp bodies with the two end faces in coaxial contact, limiting cavities are formed in the contact faces of the clamp bodies, and the two clamp bodies and the limiting cavities of the clamp bodies are in mirror symmetry along the contact faces. The device further comprises two supporting columns which are arranged at ports of the two limiting cavities respectively and matched with the ports of the two limiting cavities in structure, the periphery of any supporting column is coaxially sleeved with a supporting semi-ring, the peripheries of the two supporting semi-rings are matched with the inner periphery of the pipe sample in structure, and spaces are reserved between the peripheries of the two supporting semi-rings and the inner walls of the limiting cavities. Through reasonable arrangement of component structures, the clamp is simple in structure, reasonable in layout and convenient to disassemble, when the clamp is frequently used and abrasion fatigue failures such as pitting corrosion and scratching happen to the surfaces of the supporting semi-rings making contact with a pipe sample, only one pair of supporting semi-rings needs to be replaced, and replaceability and universality are higher; meanwhile, in the process of testing the high-temperature circumferential strength of the pipe sample, the uniform stress and deformation of the pipe sample in the high-temperature test are ensured, and the reliability and the accuracy are improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of jigs, and particularly relates to a jig for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes. Background Art

[0002] Thin-diameter and thin-wall molybdenum / molybdenum alloy tubes (wall thickness δ≤1mm) are made of molybdenum and molybdenum alloy powders. The required-sized bar blanks are pressed by a cold isostatic press, and then the pressed bar blanks are sintered in a vacuum high-temperature furnace. Then, the sintered bar blanks are forged and machined to prepare molybdenum and molybdenum alloy bars. The machined bars are drilled with deep holes to form rough tubes, and finally the rough tubes are rolled, shaped and surface-treated to prepare molybdenum and molybdenum alloy thin-wall tube products. During the high-temperature circumferential detection process, the existing jigs have low adaptability to tubes of various sizes, and the replacement cost is high when the jigs are worn.

[0003] At the same time, due to the material property that molybdenum and molybdenum alloy start to have an obvious oxidation reaction with oxygen in the air above 550°C, the high-temperature circumferential tensile test of the tubes made of this kind of easily oxidized metal material cannot be carried out normally. For the circumferential tensile performance test of molybdenum and molybdenum alloy tubes by domestic professional high-temperature mechanical property testing institutions, either there is no suitable standard as a basis, or the tensile temperature is strictly controlled below 500°C, or there is no special jig for high-temperature circumferential tensile of tubes with a reasonable structure, which seriously hinders the circumferential strength performance test of easily oxidized metal tubes such as molybdenum and molybdenum alloy above 500°C. Summary of the Invention

[0004] Aiming at the above problems, the purpose of the utility model is to provide a jig for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes, so as to solve the problems of replaceability and versatility of the jig for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes, and to avoid the uniform stress and deformation of the tube specimens during the high-temperature circumferential strength test, and improve the detection accuracy and accuracy.

[0005] To achieve the above purpose, the technical solutions adopted by the utility model include:

[0006] A jig for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes includes two jig bodies with coaxial contact at both ends. A limiting cavity is arranged on the contact surface of the jig body, and the two jig bodies and their limiting cavities are mirror-symmetrical along the contact surface; it also includes two support columns respectively arranged at the ports of the two limiting cavities and matching with their structures. A support semi-ring is coaxially sleeved on the outer periphery of any support column. The outer peripheries of the two support semi-rings match the inner periphery of the tube specimen, and there is a space between the outer peripheries of the two support semi-rings and the inner wall of the limiting cavity.

[0007] Preferably, the cross-section from the port to the inner bottom of the limiting cavity increases in sequence.

[0008] Preferably, a first limiting protrusion is provided at the contact position between the support column and one end of the support semi-ring, and a second limiting protrusion is provided at one end of the support semi-ring.

[0009] Preferably, the contact surfaces of the support column and the support semi-ring are respectively provided with a convex rail and a concave rail that are parallel to their axes and match in structure.

[0010] Preferably, a first cold liquid channel is provided around the inside of the fixture body, and the two ports at both ends of the first cold liquid channel extend outward to be a first cold liquid channel inlet and a first cold liquid channel outlet respectively.

[0011] Preferably, it further includes two cooling rods coaxially connected to the other end faces of the two fixture bodies respectively. A second cold liquid channel is provided inside the cooling rods, and the two ports at both ends of the second cold liquid channel extend outward to be a second cold liquid channel inlet and a second cold liquid channel outlet respectively.

[0012] Compared with the prior art, the advantages of the present utility model are as follows:

[0013] (1) For the fixture for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes of the present utility model, through reasonable setting of the component structure, it has a simple structure, reasonable layout, and convenient disassembly. When the fixture is frequently used and pitting, scratching and other wear fatigue failures occur on the surface of the support semi-ring in contact with the tube sample, only a pair of support semi-rings need to be replaced, and the replaceability and versatility are stronger.

[0014] (2) For the fixture for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes of the present utility model, through reasonable setting of the component structure, during the high-temperature circumferential strength test of the tube sample, the uniform stress and deformation of the tube sample during the high-temperature test are ensured, the reliability of the special fixture and the accuracy of the test results are improved, the high-temperature circumferential strength test requirements of various thin-diameter and thin-wall molybdenum or molybdenum alloy tubes are met, the accuracy of the high-temperature circumferential strength detection data is improved, the high-temperature circumferential strength test cost is reduced, and the cycle of continuous test experiments is shortened. Description of the Drawings

[0015] The drawings are used to provide a further understanding of the present utility model, and constitute a part of the specification. Together with the following specific implementation manners, they are used to explain the present utility model, but do not constitute a limitation to the present utility model. In the drawings:

[0016] Figure 1 is a schematic structural diagram of the fixture for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes of the present utility model;

[0017] Figure 2 is Figure 1 the assembly schematic diagram of the tube sample, the support column and the support semi-ring in

[0018] Figure 3 is Figure 2 the sectional view taken along the A-A direction in

[0019] Figure 4 For Figure 1 Schematic cross-sectional view of the middle support column and the support semi-ring.

[0020] The labels in the figure are as follows:

[0021] 0 Pipe specimen, 1 Fixture body, 2 Cooling rod, 3 Support column, 4 Support semi-ring;

[0022] 1-1 Limit cavity, 1-2 First cooling liquid channel, 1-21 First cooling liquid channel inlet, 1-22 First cooling liquid channel outlet;

[0023] 2-1 Second cooling liquid channel, 2-11 Second cooling liquid channel inlet, 2-12 Second cooling liquid channel outlet;

[0024] 3-1 First limit projection;

[0025] 4-1 Second limit projection, 4-2 Concave rail. Specific implementation mode

[0026] The utility model is not limited to the following specific embodiments, and all equivalent transformations made on the basis of the technical solution of this application fall within the protection scope of the utility model.

[0027] It should be noted that the directional terms mentioned in this article, such as "inner cavity", "inner circumference", "inner wall" and "outer side", etc., are all consistent with the specific directions on the paper of the specification drawings or the corresponding directions in the space shown in the drawings; all components and devices in the utility model, unless otherwise specified, all adopt the components and devices known in the prior art.

[0028] Embodiment

[0029] This embodiment discloses a fixture for thin-diameter and thin-wall molybdenum or molybdenum alloy pipes, including two fixture bodies 1 with coaxial contact at both ends. A limit cavity 1-1 is provided on the contact surface of the fixture body 1, and the two fixture bodies 1 and their limit cavities 1-1 are mirror-symmetrical along the contact surface; it also includes two support columns 3 respectively arranged at the ports of the two limit cavities 1-1 and matching their structures. A support semi-ring 4 is coaxially sleeved on the outer circumference of any one support column 3. The outer circumferences of the two support semi-rings 4 match the inner circumference structure of the pipe specimen 0, and there is a space between the outer circumferences of the two support semi-rings 4 and the inner wall of the limit cavity 1-1;

[0030] Its functions are as follows: The pipe specimen 0 is coaxially fixed and limited on the two support columns 3 by two support semi-rings 4, and is clamped and limited by two fixture bodies 1, avoiding defects such as sliding, adhesion, and detachment between the special fixture body and the support column 3, between the support semi-ring 4 and the pipe specimen 0, and between the support columns 3 during the high-temperature circumferential strength test of the pipe specimen 0. It reduces the technological links of the pipe circumferential strength test, reduces the detection cost, shortens the test cycle, improves the test efficiency, and when the surface of the support semi-ring 4 in contact with the pipe specimen 0 undergoes wear fatigue failures such as pitting and scratching after frequent use of the fixture, only a pair of support semi-rings 4 needs to be replaced, with stronger replaceability and versatility. The structure is simple, the layout is reasonable, and the disassembly is convenient. It can realize the clamping and support of pipe specimens made of various metal materials with a diameter of 6 - 25 mm and a wall thickness of δ 0.3 - 2 mm.

[0031] Specifically, a first cooling liquid channel 1-2 is provided around the inside of the fixture body 1. The two ports of the first cooling liquid channel 1-2 extend outward to be a first cooling liquid channel inlet 1-21 and a first cooling liquid channel outlet 1-22 respectively. The first cooling liquid channel 1-2 is externally connected to a circulating cooling water supply through the first cooling liquid channel inlet 1-21 and the first cooling liquid channel outlet 1-22, so as to ensure uniform stress and deformation of the pipe specimen 0 during the high-temperature circumferential strength test, improve the reliability of the special fixture and the accuracy of the test results, meet the high-temperature circumferential strength test requirements of various thin-diameter and thin-wall molybdenum or molybdenum alloy pipes, improve the accuracy of high-temperature circumferential strength detection data, reduce the high-temperature circumferential strength test cost, shorten the cycle of continuous test experiments, and fill the blank of the high-temperature circumferential tensile property test of easily oxidized metal materials above 500°C.

[0032] Specifically, it further includes two cooling rods 2 coaxially connected to the other end faces of the two fixture bodies 1 respectively. A second cooling liquid channel 2-1 is provided inside the cooling rod 2. The two ports of the second cooling liquid channel 2-1 extend outward to be a second cooling liquid channel inlet 2-11 and a second cooling liquid channel outlet 2-12 respectively. The second cooling liquid channel 2-1 is externally connected to a circulating cooling water supply through the second cooling liquid channel inlet 2-11 and the second cooling liquid channel outlet 2-12, avoiding the over-high temperature of the fixture in the furnace body, further ensuring uniform stress and deformation of the pipe specimen 0 during the high-temperature test, and improving the reliability of the special fixture and the accuracy of the test results.

[0033] In this embodiment, the cooling rod 2 is made of stainless steel metal materials such as 304 or 316. The fixture body 1, the support column 3, and the support semi-ring 4 are all made of high-temperature resistant materials, and molybdenum rhenium alloy is preferably selected, so that the fixture has a certain red hardness in the ultra-high temperature working environment, increasing the service life and use frequency of the fixture.

[0034] The cross-section of the limiting cavity 1-1 of the present embodiment gradually increases from the port to the inner bottom to play a role in limiting and clamping the support 3. A first limiting protrusion 3-1 is provided at the contact between the support column 3 and one end of the support semi-ring 4, and a second limiting protrusion 4-1 is provided at one end of the support semi-ring 4. The limiting protrusions are both shoulders to achieve the coincidence of the support column 3, the support semi-ring 4, and the pipe specimen 0 with the plane perpendicular to the midpoint of their axes. The contact surfaces of the support column 3 and the support semi-ring 4 are respectively provided with a convex rail and a concave rail 4-2 parallel to their axes and matching in structure to improve the positioning accuracy of the support column 3 and the support semi-ring 4, ensure the coaxiality of the length center line of the pipe specimen 0 and the center lines of the upper and lower connecting rods of the four-column testing machine, and avoid inaccurate or invalid measurement data caused by the deviation of the center line during the circumferential strength tensile process.

[0035] The preferred embodiments of the present disclosure have been described in detail above in conjunction with the accompanying drawings. However, the present disclosure is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0036] In addition, it should be noted that, in the above specific embodiments, the various specific technical features described can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present disclosure will not separately describe various possible combination methods.

[0037] Furthermore, any combination can be made between the various different embodiments disclosed in this solution as long as it does not violate the idea of the present disclosure, and it should also be regarded as the content invented by the present disclosure.

Claims

1. A fixture for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes, characterized in that, It includes two fixture bodies (1) with their two end faces in coaxial contact. A limiting cavity (1-1) is provided on the contact surface of the fixture body (1), and the two fixture bodies (1) and their limiting cavities (1-1) are mirror-symmetrical along the contact surface; It also includes two support columns (3) respectively arranged at the ports of the two limiting cavities (1-1) and matching their structures. A support semi-ring (4) is coaxially sleeved on the outer periphery of any one of the support columns (3). The outer peripheries of the two support semi-rings (4) match the inner periphery structure of the pipe sample (0), and there is a space between the outer peripheries of the two support semi-rings (4) and the inner wall of the limiting cavity (1-1).

2. The fixture for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes as described in claim 1, wherein The cross-section of the limiting cavity (1-1) from the port to the inner bottom increases in sequence.

3. The fixture for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes as described in claim 1, wherein A first limiting protrusion (3-1) is provided at the contact position between the support column (3) and one end of the support semi-ring (4), and a second limiting protrusion (4-1) is provided at one end of the support semi-ring (4).

4. The clamp for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes according to claim 1, wherein Convex rails and concave rails (4-2) parallel to their axes and matching their structures are respectively provided on the contact surfaces of the support column (3) and the support semi-ring (4).

5. The fixture for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes according to any one of claims 1-4, characterized in that, A first cold liquid channel (1-2) is provided around the inside of the fixture body (1). The two end ports of the first cold liquid channel (1-2) extend outwards to be a first cold liquid channel inlet (1-21) and a first cold liquid channel outlet (1-22) respectively.

6. The fixture for thin-diameter and thin-wall molybdenum or molybdenum alloy tubes as described in claim 5, characterized in that, It also includes two cooling rods (2) coaxially connected to the other end faces of the two fixture bodies (1) respectively. A second cold liquid channel (2-1) is provided inside the cooling rod (2). The two end ports of the second cold liquid channel (2-1) extend outwards to be a second cold liquid channel inlet (2-11) and a second cold liquid channel outlet (2-12) respectively.

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