CN216525162U

CN216525162U - Tool for breakage tension test of joint with rotating nut

Info

Publication number: CN216525162U
Application number: CN202122677485.6U
Authority: CN
Inventors: 李东敏; 陈国权; 马飞亚
Original assignee: Harbin Aircraft Industry Group Co Ltd
Current assignee: Harbin Aircraft Industry Group Co Ltd
Priority date: 2021-11-03
Filing date: 2021-11-03
Publication date: 2022-05-13
Anticipated expiration: 2031-11-03

Abstract

The application provides a frock for taking swivel nut to connect destruction tensile test, the frock includes: a bushing having an internal thread; wherein the internal thread is matched with the external thread with a rotary nut joint; a bracket connected with the bushing; a round bar having an external thread; wherein the external thread is matched with the internal thread with the rotary nut joint; when a destructive tension test is carried out, the bracket is connected with an upper chuck of a tensile machine, and the round bar is connected with a lower chuck of the tensile machine; the application provides an experimental frock, in whole test process, experimental frock closely cooperates with testpieces and testing machine, and experimental power has been transmitted effectively to the testpieces through experimental frock.

Description

Tool for breakage tension test of joint with rotating nut

Technical Field

The application belongs to the technical field of tensile test, especially, relate to a frock for taking swivel nut to connect destruction tensile test.

Background

The nut and the bolt commonly used in the aviation industry need to be subjected to a tensile test, but the shape of the commonly used nut and bolt is regular, a plurality of single parts are provided, the tool structure is simple, and the test method is convenient. However, the joint with the rotating nut in the application is irregular in shape and formed by combining two parts, and if no corresponding test tool exists, the joint cannot be matched with an electronic tensile testing machine. Therefore, the test method of the failure test needs to be researched, and a tool for the failure tensile test is provided.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the application provides a frock that is used for taking swivel nut to connect destruction tensile test, the frock includes:

a bushing having an internal thread; the internal thread is matched with the external thread with the rotary nut joint;

a bracket connected with the bushing;

a round bar having an external thread; wherein the external thread is matched with the internal thread with the rotating nut joint.

Preferably, when the breaking tension test is carried out, the bracket is connected with an upper chuck of the tensile machine, and the round rod is connected with a lower chuck of the tensile machine.

Preferably, the stent is an "internal" stent.

Preferably, the bracket comprises:

and the fixing block is used for fixing the assembled bushing and the joint with the rotary nut.

Preferably, concentric holes are arranged on the outer walls of two sides of the bracket; wherein the concentric holes are used to connect the bushings.

Preferably, the joint with the rotary nut comprises a T-shaped tee joint and a tightening nut.

The application has the following technical effects:

the application provides an experimental frock, in whole test process, experimental frock closely cooperates with testpieces and testing machine, and experimental power has been transmitted effectively to the testpieces through experimental frock.

Drawings

Fig. 1 is a schematic structural diagram of an assembled test tool and a joint with a rotating nut provided in an embodiment of the present application;

FIG. 2 is a schematic structural view of a joint with a rotating nut and a bushing according to an embodiment of the present disclosure after assembly;

wherein: 1-a scaffold; 2-round bar; 3-lining.

Detailed Description

Referring to fig. 1-2, the present application provides a fitting with a swivel nut, the fitting with a swivel nut being characterized in that: the part three-way joint is assembled with standard part tightening nuts HB4-49-6CDD respectively and then is formed by compression. The assembly formed after compression is called a joint with a rotating nut, the middle hole of the three-way joint is a through hole, and both ends of the through hole are provided with external threads for connecting with other connecting pieces.

The through hole of the joint is a reducing hole, the sizes of the external threads on the two sides are different, one side is large, and the other side is small. The base of the joint is provided with a rotating nut. The number of the fittings is 8, and the specific figure number and the size of the joint are shown in the table 1.

TABLE 1

In the examples of the present application, the test requirements of the breaking force test; according to the specification of a drawing: and (3) extracting not less than 3 static load breaking tension tests from each batch of parts with the same size, wherein the breaking tension is 30KN, and if one part is unqualified, taking the double number of parts to perform the tests again.

It should be noted that, in the joint drawing with the swivel nut, only the acceptance value of the breaking tension test is specified, no test method is specified, and the physicochemical room has not been subjected to similar tests before, and has no test experience in this respect, so that the test difficulty is large.

In the embodiment of the application, the design of the test scheme of the breaking tension of the joint with the rotating nut is adopted. Introduction of a chuck structure of an electronic tensile machine; the clamping device of the electronic tensile machine is divided into an upper clamping head device and a lower clamping head device, the upper clamping head and the lower clamping head of the testing machine respectively clamp the clamping parts at two ends of a sample during testing, in the stretching process, the upper clamping head and the lower clamping head simultaneously apply axial tensile stress to the sample at the same testing speed, and the axis of the sample is consistent with the axis of the clamping head of the testing machine.

Among them, the types of tensile test pieces are generally divided into rectangular tensile test pieces and circular tensile test pieces, and the electronic tensile machine is generally equipped with two types of chucks: the electronic tensile machine comprises a flat wedge-shaped chuck and a V-shaped groove chuck, wherein the specifications of the chuck of the electronic tensile machine are respectively matched with the thickness or the diameter of a tensile sample, the flat wedge-shaped chuck is used for clamping rectangular tensile samples with various thicknesses, and the V-shaped groove chuck is used for clamping circular tensile samples with various diameters.

In the embodiment of the application, a test tool is designed and manufactured, the connection between the joint with the rotary nut and the electronic tensile machine is firstly realized in the breaking tensile test, and as can be seen from the above, the electronic tensile machine can only clamp a plate-shaped sample or a circular sample and can not clamp a T-shaped part, so that the test tool is required to be used as a transition between the sample and the tensile machine to complete the test.

In the embodiment of the application, the tool design scheme is as follows: by means of external threads on both sides of the through-hole portion of the joint. As can be seen from table 1, a total of 8 fittings, involving a total of 8 thread sizes, 8 internally threaded bushings 3 were designed, the external diameters of which were all the same size, except that the internal thread of the bushing matched the external thread size of the joint. The design is also an 'inner' shaped bracket 1, concentric holes are arranged on the outer walls of the two sides of the 'inner' shaped bracket to connect with the lining, during the test, firstly, the lining matched with the external threads of the two sides of the joint is selected, and the lining is assembled with the joint. The inner bracket is provided with a fixed block for fixing the assembled bushing and the joint, and is connected with an upper chuck of a tensile machine. A round rod 2 with external threads is designed at the connecting part of the rotary nut end of the joint and the lower chuck of the tensile machine, the external threads are matched with the internal threads of the rotary nut, and the round rod is used for connecting the rotary nut end and the lower chuck of the tensile machine.

In the examples of the present application, determination of the assay rate; in the aviation standard test method, the test rate is specified in 3.3.6 specifications in HB4-48-2002 flared tightening nut combination technical requirement, at least 3 tightening nuts with the same specification are extracted from each batch of tightening nuts to carry out a destructive tension test, the destructive tension is only used for checking the tightening nuts, and a process nozzle is allowed to be adopted during the test. HB4-48-2002 only specifies the proof value of breaking tension in the breaking tension test, and the test rate of the breaking tension test is not given, so that the method cannot be used for reference. The test rate specified in the national military standard test method, and the 4.2 loading rate specified in GJB715.23A-2008 "tensile strength of fastener test method", should apply a tensile load slowly and smoothly to the test specimen, with the loading rate specified in table 2. The spin nut assembled in the sample spin nut fitting was HB4-49-6CDD, the nominal diameter of the nut was 14, and the loading rate was 108KN/min as per Table 2.

Further, tests prove that the loading rate is set to be 108KN/min reasonably for the breaking tension test with the rotary nut joint.

TABLE 2

In the examples of the present application, the design of the basic process was tested. Firstly, a sample is sampled; and receiving the sample, and checking the surface quality of the sample and the free rotation degree of the rotating nut at the bottom end of the joint. Secondly, the testing steps are as follows: 1) measuring the sizes of the threads on the two sides of the through hole part of the joint by using a vernier caliper; 2) selecting a bushing matched with the through hole part of the joint according to the sizes of the threads on the two sides of the through hole part of the joint, and connecting the bushing with the joint; 3) connecting the assembly after the bushing and the joint with the inner-shaped bracket by using a fixing block, and fixing the assembly with the inner-shaped bracket by using a bolt; 4) assembling a round rod with external threads and a rotating nut with a rotating nut joint; 5) connecting the assembled inner-shaped bracket assembly with an upper chuck of a tensile machine; 6) adjusting the position of the assembly of the bushing and the joint to enable the center of the joint to be consistent with the center of the axis of the chuck of the tension machine; 7) connecting a round rod assembled with a rotating nut of a joint with a lower chuck of a tensile machine; 8) entering a test program, establishing a test file, and inputting related information of a joint with a rotating nut; 9) setting the loading rate of the test to be 108KN/min, and setting the maximum tensile load of the test to be 30 KN; 10) starting a test, and observing the change of the joint in the loading process; 11) when the test load reaches 30KN, stopping loading, and finishing the breaking tension test of one joint; 12) unloading the load, opening the upper and lower chucks of the tensile machine, removing the joint from the test tool, and replacing another sample; 13) mounting the assembled sample and the test tool on a tensile machine, and starting a test of a second sample; 14) and finishing the test after the test of the third sample is finished.

The application provides totally 8 kinds of joints, relates to 8 kinds of thread sizes totally, so designed 8 take the internal thread, and the equal same bush of external diameter, the internal thread of this 8 kinds of bushes respectively with the external thread size phase-match of 8 kinds of joints. A round rod with external threads is designed by utilizing the rotating nut end of the joint, the external threads are matched with the internal threads of the rotating nut, and the round rod is used for completing the connection of a test piece and a lower chuck of a tensile machine. The application designs an 'inner' shaped bracket, and the upper end of the 'inner' shaped bracket is designed into a flat plate shape and is connected with an upper chuck of a tensile machine. The two sides of the inner-shaped bracket are provided with concentric holes for placing the bushings. During testing, firstly, the lining matched with the external threads on the two sides of the joint is selected, and the lining and the joint are assembled. Then the joint with the assembled bushing is placed in the inner frame, and two ends of the joint are tightly connected through bolts. The test speed is regulated, the deformation of the sample can be well controlled in the test, and the whole test process is more standard. After the test method is used for testing, the test curve is coherent, the test load is accurate, and the whole test process is stable and has no abnormity. The experiment tool, the test piece and the tester are in close fit in the whole experiment process, and the experiment force is effectively transmitted to the test piece through the experiment tool. A new method for testing the breaking tension of the joint with the rotary nut is established, the tool structure is clear, the test parameters are clear, and the operation specifications are provided for the future tests.

In other embodiments of the present application, a certain type of machine is a joint with a rotating nut, the number of the component is XX-3322422160-001, the joint is in a three-way pipe "T" shape, the lower part of the joint is formed by compressing the nut, the joint is asymmetric in left and right dimensions and structure, and the test requirements are as follows: and (3) extracting not less than 3 static load breaking tension tests from each batch of parts with the same size, wherein the breaking tension is 30KN, and if one part is unqualified, taking the double number of parts to perform the tests again.

The test method is used for testing the joint with the rotating nut, the test curve is coherent, the test load is accurate, and the whole test process is stable and has no abnormity. The conclusion is that the test method is feasible and effective.

In other embodiments of the present application, a universal standard, a tee fitting with a swivel nut, assembly numbers XX759-22, test requirements: and carrying out an axial tension test, wherein the axial tension is more than or equal to 2.77 KN.

The three-way pipe joint with the rotary nut is tested by the testing method, the testing curve is coherent, the testing load is accurate, the testing tool is tightly matched with the test piece and the testing machine in the whole testing process, the testing force is effectively transmitted to the test piece through the testing tool, and the testing process is free of abnormity. The conclusion is that the test method is feasible and effective.

Claims

1. The utility model provides a frock for taking swivel nut to connect destruction tensile test which characterized in that, the frock includes:

a bracket connected with the bushing;

2. The tool for the joint destructive tension test with the swivel nut as claimed in claim 1, wherein the bracket is connected with an upper chuck of a tensile machine and the round bar is connected with a lower chuck of the tensile machine during the destructive tension test.

3. The tooling for the breaking tension test of a joint with a swivel nut of claim 2, wherein the bracket is an "inner" shaped bracket.

4. The tooling for the joint breaking tension test with the swivel nut of claim 3, wherein the bracket comprises:

5. The tool for the joint breaking tension test with the rotating nut as claimed in claim 3, wherein concentric holes are formed in the outer walls of the two sides of the support; wherein the concentric holes are used to connect the bushings.

6. The tool for the joint breaking tension test with the rotating nut as claimed in claim 1, wherein the joint with the rotating nut comprises a T-shaped tee pipe joint and a tightening nut.