CN110823682A - Clamp for ultrahigh-temperature creep test - Google Patents

Abstract

A fixture for ultra-high temperature creep test, comprising: two connecting pieces (1) and two U-shaped bases (2); the U-shaped base (2) includes two side walls (21) arranged in parallel, and The transverse arms (22) connected between the two side walls (21), the openings of the two U-shaped bases (2) are opposite and the two transverse arms (22) are perpendicular to each other; one end of the two connecting pieces (1) are respectively It is detachably connected with the openings of the two U-shaped bases (2), and the other ends of the two connecting pieces (1) are installed on the high temperature creep device. It has good high-temperature comprehensive performance and excellent thermal fatigue performance, and can apply a stable load to the tested sample for a long time under the condition of 1000 ℃ or higher; at the same time, the external compressive stress applied to the tested sample can be based on the tensile stress at both ends of the fixture. Calculated directly, the result is accurate and reliable.

Description

A fixture for ultra-high temperature creep test

technical field

The invention relates to the technical field of high temperature creep, in particular to a fixture for ultra-high temperature creep test.

Background technique

High temperature creep refers to the phenomenon that metal materials slowly produce plastic deformation under the long-term action of constant temperature and constant load. Under high temperature conditions, the effect of creep on components is very significant. Due to the different ways of applying stress, it can be divided into high temperature compression creep, high temperature tensile creep, high temperature bending creep and high temperature torsional creep. Compared with high temperature strength, high temperature creep can more effectively predict the strain trend and fracture life of the material when it is used for a long time at high temperature. It is one of the important mechanical properties of the material and is related to the material and structural characteristics of the material.

High temperature creep performance is an important index to evaluate the mechanical properties of materials. There are mature experimental methods for high temperature tensile creep and high temperature compression creep experiments of materials in China, and corresponding national standards have been formulated. And high-temperature compression creep experimental equipment is also emerging in the market, but there is currently no compression creep device and tensile creep device above 1000 ° C. The material of the current compression creep device is cemented carbide, only Compression creep test can be performed below 800°C.

SUMMARY OF THE INVENTION

(1) Purpose of the invention

The purpose of the present invention is to provide a fixture for ultra-high temperature creep test. By using DZ22 material and DZ125 material to make the fixture, the fixture can perform high temperature compression creep test in an environment above 1000°C.

(2) Technical solutions

In order to solve the above problems, according to one aspect of the present invention, the present invention provides a fixture for ultra-high temperature creep test, comprising: two connecting pieces and two U-shaped bases; The side walls and the transverse arms connected between the two side walls, the openings of the two U-shaped bases are opposite and the two transverse arms are perpendicular to each other; one end of the two connecting pieces is detachably connected to the openings of the two U-shaped bases respectively , the other ends of the two connectors are installed on the high temperature creep device.

Further, a first connecting hole is provided on the side wall near the opening of the U-shaped base, and one end of the connecting piece is provided with a second connecting hole, and the second connecting hole corresponds to the first connecting hole; the pins pass through the first connecting hole in turn. A connecting hole and a second connecting hole enable the connecting piece to be detachably connected to the U-shaped base.

Further, the connecting piece includes: a first connecting part and a second connecting part that are fixedly connected; the first connecting part is a cylindrical threaded connecting piece, which is detachably connected to the pull rod of the high temperature creep device; the second connecting part is connected to the U The base is detachably connected, and the second connection hole is arranged on the second connection part.

Further, the connecting piece, the U-shaped base, and the pin are made of DZ125 material.

Further, the tie rod of the high temperature creep device is made of DZ22 material.

Further, the calculation formula of the external compressive stress applied on the tested sample is:

σ=F/N;

Among them, σ is the external compressive stress exerted on the tested sample, F is the tensile force received by the connector, and N is the stressed area of the tested sample. .

Further, the thread of the first connection part is manufactured according to 6g precision; the coaxiality between the center of the thread of the first connection part and the first connection part does not exceed 0.01 mm.

Further, the coaxiality between the tie rod and the first connecting portion is not more than 0.05mm, and is interchangeable.

Further, the axis of the second connecting hole and the center line of the longitudinal axis of the first connecting hole perpendicularly intersect, and the displacement and perpendicularity are not greater than 0.05mm; the axis of the second connecting hole is perpendicular to the two planes of the slot exceeding 0.05mm.

Further, the parallelism of the two side walls of the U-shaped base to the center of its longitudinal axis shall not be greater than 0.1 mm in the entire length; more than 0.05mm.

(3) Beneficial effects

The above-mentioned technical scheme of the present invention has the following beneficial technical effects:

Simple structure, easy to install and use;

The high temperature tensile creep clamp adopts DZ22 material, and the high temperature compression creep clamp adopts DZ125 material, which has good high temperature comprehensive performance and excellent thermal fatigue performance, and can apply a stable load to the tested sample for a long time under the condition of 1000℃ or higher. ;

The external compressive stress applied to the sample to be tested can be directly calculated according to the tensile stress at both ends of the clamp of the present application, and the result is accurate and reliable.

Description of drawings

Fig. 1 is the structure diagram of the clamp for ultra-high temperature creep test provided by the present invention;

Fig. 2 is the sectional view of the clamp for ultra-high temperature creep test provided by the present invention;

Fig. 3 is the perspective view of the clamp for ultra-high temperature creep test provided by the present invention;

Fig. 4 is the structural diagram of the U-shaped base of the clamp for ultra-high temperature creep test provided by the present invention;

Fig. 5 is the structural diagram of the connector of the clamp for ultra-high temperature creep test provided by the present invention;

Fig. 6 is the dimension drawing of the connector of an embodiment of the fixture for ultra-high temperature creep test provided by the present invention;

FIG. 7 is a dimension drawing of a U-shaped base of an embodiment of the fixture for ultra-high temperature creep test provided by the present invention.

Reference number:

1-connector; 2-U-shaped base; 3-pin; 11-second connection hole; 12-first connection part; 13-second connection part; 14-washer; 21-side wall; 22-transverse arm; 23-the first connecting hole.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the specific embodiments and the accompanying drawings. It should be understood that these descriptions are exemplary only and are not intended to limit the scope of the invention. Also, in the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily obscuring the concepts of the present invention.

The present invention will be described in detail below with reference to the accompanying drawings and embodiments.

Fig. 1 is a structural diagram of a fixture for ultra-high temperature creep test provided by the present invention, Fig. 2 is a cross-sectional view of a fixture for ultra-high temperature creep test provided by the present invention, and Fig. 3 is provided by the present invention for ultra-high temperature A perspective view of the jig for the creep test.

The present invention provides a fixture for ultra-high temperature creep test, comprising: two connecting pieces 1 and two U-shaped bases 2; the U-shaped base 2 includes two side walls 21 arranged in parallel, and a For the transverse arms 22 between the side walls 21, the openings of the two U-shaped bases 2 are opposite and the two transverse arms 22 are perpendicular to each other; The other end of each connector 1 is installed on the high temperature creep device.

Optionally, the U-shaped base 2 is formed by bending a rectangle with a rectangular cross-section, or by welding the transverse arm 22 and the two side walls 21, wherein one end of the two parallel side walls 21 is open, and the other end is The cross arm 22 is connected.

When in use, each component in the fixture of the present application is in a disassembled state, the openings of the two U-shaped bases 2 are opposite and the planes of the two transverse arms 22 are perpendicular to each other, and the tested sample is first placed on the two transverse arms 22. between the planes, and then combine other parts of the fixture. Finally, the two connectors 1 are respectively connected to the tie rods of the high temperature creep device, and the compression creep test can be carried out.

Specifically, when the high-temperature tensile creep test is performed, the two ends of the tested sample are directly installed on the tie rod of the high-temperature creep device, and a tensile force is applied to the tie rod of the high-temperature creep device. At this time, the two ends of the tested sample are subjected to The tensile force in the opposite direction stretches the tested sample to achieve the effect of tensile creep.

Preferably, a sleeve is connected to the tie rod of the high temperature creep device. The sleeve is hollow and has internal threads. Both ends of the sample to be tested are respectively connected with the sleeve thread.

Optionally, the sample to be tested and the sleeve can also be connected by snaps.

When the high temperature compression creep test is performed, the sample to be tested is first placed between the two transverse arms 22 of the two U-shaped bases 2, then the combined fixture is performed, and finally the combined fixture with the tested sample is installed on the on the tie rod of the high temperature creep device. When a pulling force is applied to the tie rod of the high temperature creep device, at this time, the two transverse arms 22 are respectively subjected to the pulling force in the opposite direction and move closer to each other, thus causing the tested sample arranged between the two transverse arms 22 to be squeezed and subjected to compressive stress. , the applied tensile stress is transformed into compressive stress, so as to achieve the effect of compressive creep.

In one embodiment, a first connecting hole 23 is provided on the side wall 21 near the opening of the U-shaped base 2 , and one end of the connecting piece 1 is provided with a second connecting hole 11 , and the second connecting hole 11 is connected to the first connecting hole. 23 corresponds to; the pin 3 passes through the first connecting hole 23 and the second connecting hole 11 in sequence, so that the connecting piece 1 and the U-shaped base 2 are detachably connected.

Specifically, the connector 1 can not only connect and fix two U-shaped bases 2 that are perpendicular to each other and have opposite openings, but also can fix the entire clamp so that it is not deviated from the direction while being subjected to tensile stress during use, and can be compressed more accurately Tested samples to improve compression quality and accuracy.

In one embodiment, the connector 1 includes: a first connecting part 12 and a second connecting part 13 that are fixedly connected; the first connecting part 12 is a cylindrical threaded connector that is detachably connected to the pull rod of the high temperature creep device ; The second connecting portion 13 is provided with a second connecting hole 11 .

Specifically, the second connection part 13 is used to connect and fix the U-shaped base 2; the cylindrical threaded connection is matched with the sleeve connected to the pull rod of the high temperature creep device, so as to fix the clamp on the high temperature creep device.

In one embodiment, the connector 1, the U-shaped base 2, and the pin 3 are made of DZ125 material.

In one embodiment, the tie rod of the high temperature creep device is made of DZ22 material.

Specifically, the above-mentioned materials can enable the tested samples to undergo high-temperature tensile or compressive creep tests in an environment above 1000 °C, and the clamps made of this material have a long service life and are not easy to break; High precision and good quality of extension or compression.

In one embodiment, the calculation formula of the external compressive stress applied on the tested sample is:

σ=F/N;

Among them, σ is the external compressive stress exerted on the tested sample, F is the tensile force on both ends of the connector 1, and N is the stressed area of the tested sample.

Specifically, when a high-temperature tensile creep test is performed, both ends of the tested sample are subjected to an applied tensile stress; when a high-temperature compressive creep test is performed, the tested sample is subjected to a compressive stress transformed from the applied tensile stress. . At this time, the tensile stress applied to the two ends of the two connecting parts 1 of the fixture is the external compressive stress on the sample to be tested; the contact area between the planes of the transverse arms 22 of the two U-shaped bases 2 and the sample to be tested is the sample to be tested the force area.

The jig of the present application will be described by the following examples.

Example:

FIG. 6 is a dimension drawing of the connector 1 of an embodiment of the fixture for ultra-high temperature creep test provided by the present invention, and FIG. 7 is a U of an embodiment of the fixture for ultra-high temperature creep test provided by the present invention Dimensional drawing of type base 2. Please refer to Figure 6 and Figure 7, where the unit is millimeters. The first connecting portion 12 is a stud with an outer diameter of M18, and its length is 60 mm, and the thread of the first connecting portion 12 is manufactured with an accuracy of 6g. In order to ensure the accuracy of the compression test, and at the same time, the clamp does not shift during use, the coaxiality between the thread center of the first connecting portion 12 and the first connecting portion 12 does not exceed 0.01 mm.

Preferably, the coaxiality between the sleeve on the tie rod and the first connecting portion 12 is not more than 0.05mm, and is interchangeable to ensure that it can adapt to different samples to be tested.

Preferably, the second connection portion 13 is a cube, the diameter of the second connection hole 11 is 8.5 mm, and the center of the second connection hole 11 is set at the center of the cube. The diameter of the first connecting hole 23 is the same as that of the second connecting hole 11 , and it is provided on the side wall 21 at a distance of 15 mm from the opening position. The axis of the second connection hole 11 and the center line of the longitudinal axis of the first connection hole 23 intersect vertically, and the installation accuracy is ensured, and the displacement and verticality are not greater than 0.05mm; the axis of the second connection hole 11 is perpendicular to the two planes of the slot The degree exceeds 0.05mm.

Preferably, the parallelism of the two side walls 21 of the U-shaped base 2 to the center of its longitudinal axis is not greater than 0.1 mm in the entire length; Coincidence, the displacement exceeds 0.05mm.

The above parameters and accuracy requirements ensure that neither the fixture nor the tested sample will shift in position during the process of applying stress to the tested sample, ensuring that the tested sample is subjected to accurate compressive stress during the test. At the same time, it can ensure that the final calculated compressive stress is accurate and reliable.

The present invention aims to protect a fixture for ultra-high temperature creep test, comprising: two connecting pieces 1 and two U-shaped bases 2; the U-shaped base 2 includes two side walls 21 arranged in parallel, For the transverse arms 22 between the side walls 21, the openings of the two U-shaped bases 2 are opposite and the two transverse arms 22 are perpendicular to each other; The other ends of the two connecting pieces 1 are installed on the high temperature creep device. The structure is simple, easy to install and use; the high temperature tensile creep clamp adopts DZ22 material, and the high temperature compression creep clamp adopts DZ125 material, which has good high temperature comprehensive performance and excellent thermal fatigue performance. A stable load is applied to the sample to be tested over time; the external compressive stress applied to the sample to be tested can be directly calculated according to the tensile stress at both ends of the clamp of the present application, and the result is accurate and reliable.

It should be understood that the above-mentioned specific embodiments of the present invention are only used to illustrate or explain the principle of the present invention, but not to limit the present invention. Therefore, any modifications, equivalent replacements, improvements, etc. made without departing from the spirit and scope of the present invention should be included within the protection scope of the present invention. Furthermore, the appended claims of this invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalents of such scope and boundaries.

Claims (10)

1. A clamp for ultra-high temperature creep test, comprising: two connecting pieces (1) and two U-shaped bases (2);

the U-shaped base (2) comprises two side walls (21) which are arranged in parallel and a cross arm (22) connected between the two side walls (21), the openings of the two U-shaped bases (2) are opposite, and the two cross arms (22) are perpendicular to each other;

one end of each of the two connecting pieces (1) is detachably connected with the opening of the corresponding U-shaped base (2), and the other end of each of the two connecting pieces (1) is installed on the high-temperature creep device.

2. The clamp of claim 1,

a first connecting hole (23) is formed in the position, close to the opening of the U-shaped base (2), of the side wall (21), a second connecting hole (11) is formed in one end of the connecting piece (1), and the second connecting hole (11) corresponds to the first connecting hole (23);

the pin (3) sequentially penetrates through the first connecting hole (23) and the second connecting hole (11), so that the connecting piece (1) is detachably connected with the U-shaped base (2).

3. The clamp according to claim 1, characterized in that said connecting element (1) comprises: a first connecting part (12) and a second connecting part (13) which are fixedly connected;

the first connecting part (12) is a cylindrical threaded connecting piece and is detachably connected to a pull rod of the high-temperature creep device;

the second connecting portion (13) is detachably connected with the U-shaped base (2), and the second connecting hole (11) is formed in the second connecting portion (13).

4. The clamp of claim 1,

the connecting piece (1), the U-shaped base (2) and the pin (3) are made of DZ125 materials.

5. The clamp of claim 1,

the pull rod of the high-temperature creep device is made of DZ22 material.

6. The jig of claim 1, wherein the applied compressive stress on the sample under test is calculated by the formula:

σ＝F/N；

wherein, sigma is the applied compressive stress applied on the tested sample, F is the tensile force applied on the connecting piece (1), and N is the stress area of the tested sample.

7. The clamp of claim 4,

the thread of the first connection (12) is made with a 6g precision;

the coaxiality of the thread center of the first connecting part (12) and the first connecting part (12) is not more than 0.01 mm.

8. The clamp of claim 1,

the coaxiality of the pull rod and the first connecting part (12) is not more than 0.05mm, and the pull rod and the first connecting part have interchangeability.

9. The clamp of claim 1,

the axis of the second connecting hole (11) is vertically intersected with the longitudinal axis center line of the first connecting hole (23), and the displacement degree and the verticality are not more than 0.05 mm;

the perpendicularity of the axis of the second connecting hole (11) to the two planes of the groove exceeds 0.05 mm.

10. The clamp of claim 1,

the parallelism of the two side walls (21) of the U-shaped base (2) to the longitudinal axis center thereof is not more than 0.1mm in the whole length range;

the symmetry planes of the two side walls (21) of the U-shaped base (2) are coincident with the center line of the longitudinal axis of the U-shaped base, and the displacement degree exceeds 0.05 mm.

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