A pin weld strength testing device and method

Abstract

The application discloses a pin welding strength test device and method, which comprises a tensile testing machine, wherein the tensile testing machine comprises a base and an upper cross beam capable of moving up and down relative to the base and used for applying upward tension to the pin; an upper chuck is arranged on the upper cross beam; an arc-shaped plate is welded to the pin; a fixing device for fixing the arc-shaped plate is arranged on the base; one end of the pin is welded to the pin; and the upper chuck is used for clamping the other end of the pin. The arc-shaped plate has the same outer arc-shaped profile surface as the cooling coil, the connection between the pin and the cooling coil is actually the connection between the pin and the arc-shaped surface, the tensile strength of the welding position between the pin and the arc-shaped plate is detected, the test result of the actual welding strength between the pin and the cooling coil is obtained, the similarity between the experimental and actual use states is improved, and the reliability of the experimental result is improved.

Description

Technical Field

[0001] The present invention relates to the field of welding technology, and in particular to a pin welding strength testing device and method. Background Art

[0002] The gasifier is a key component of a coal gasification plant. Because the gasifier operates at high temperatures and high pressures, the refractory lining surrounding the cooling coils within the furnace is susceptible to burnout. Remaining refractory lining residue must be removed from the furnace, and the remaining pins securing the refractory lining must be removed and re-welded. Pin welding is a welding method that uses no filler metal. Instead, a ceramic ring surrounding the pin end provides local protection before welding. During welding, the entire end face of the pin is welded to the workpiece. During welding, the pin end contacts the workpiece. Power is applied to ignite an arc, heating and melting the connecting surface between the pin end and the workpiece. Once the connecting surface is fully melted, power is removed and pressure is immediately applied to press the pin against the workpiece. The molten pin end fuses with the molten pool on the workpiece surface and solidifies, completing the connection.

[0003] In order to ensure the welding quality and verify the feasibility of the welding process, a welding process assessment is required before welding to test whether the mechanical properties of the welded joint - the tensile strength - meet the requirements. Since the pin is actually welded to the curved surface of the cooling coil, the curvature of the curved surface of the cooling coil is large, and the curvature of the curved surface has a certain impact on the strength of the weld. Therefore, the conventional method of welding the pin to the experimental rod made of the same material as the cooling coil does not conform to the actual usage scenario. The similarity between the experiment and the actual usage status is poor, and the credibility of the experimental results is poor. Summary of the Invention

[0004] In order to solve the problem that it is inconvenient to test the welding strength of pins and arc surfaces with high similarity, the present invention proposes a pin welding strength test device and method, which is convenient for detecting the welding strength of pins and arc surfaces, improves the similarity between the experiment and the actual use state, and improves the credibility of the experimental results.

[0005] The technical solution adopted by the present invention is to design a pin welding strength testing device, including a tensile testing machine, the tensile testing machine including a base and an upper beam that can move up and down relative to the base for applying an upward pulling force to the pin, an upper chuck provided on the upper beam, and also including an arc-shaped plate welded to the pin, a fixing device for fixing the arc-shaped plate is provided on the base, one end of the pin is welded to the pin, and the upper chuck is used to clamp the other end of the pin.

[0006] In some embodiments, the arc plate fixing device includes a lower cross beam, the two ends of which are fixedly connected to the base through a connector, the lower cross beam has an arc-shaped contour surface for fixing the arc plate, and also includes a stretching device for controlling the two ends of the arc plate to move upward or downward synchronously.

[0007] In some embodiments, the stretching device includes two telescopic cylinders fixed on the base, and the telescopic rods of the two telescopic cylinders are respectively connected to two ends of the arc plate.

[0008] In some embodiments, a plurality of the pins are provided on the arc-shaped plate along the length direction of the lower cross beam, and the telescopic cylinder is connected to the base via a sliding connection mechanism, which enables the telescopic cylinder to move along the length direction of the lower cross beam.

[0009] In some embodiments, an arc-shaped contour surface guide roller for supporting the arc-shaped plate is provided on the arc-shaped contour surface of the lower cross beam.

[0010] In some embodiments, the cross section of the lower beam is circular.

[0011] In some embodiments, the arc length of the arc-shaped plate is greater than the arc length of the semicircle of the cross section of the lower beam.

[0012] In some embodiments, the lower cross beam is provided with a through hole for the pin to pass through.

[0013] In some embodiments, the cross section of the lower cross beam is semicircular; and both ends of the lower cross beam are rotatably connected to the connector.

[0014] An experimental method for the pin welding strength test device comprises the following steps: first, welding the pin to the arc-shaped plate; then, clamping and fixing the end of the pin using the upper clamp so that the end of the arc-shaped plate is connected to the arc-shaped plate fixing device; then, stretching the pin upward using the upper crossbeam; and during the stretching process, detecting the stretched length of the pin and the pulling force of the upper crossbeam on the pin until the weld between the pin and the arc-shaped plate is separated.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The curved plate of the present invention has the same outer curved profile as the cooling coil. The connection between the pin and the cooling coil is effectively the connection between the pin and the curved surface. By testing the tensile strength of the weld between the pin and the curved plate, we can obtain results that are closer to the actual weld strength test results between the pin and the cooling coil, improving the similarity between the experimental and actual use conditions and enhancing the credibility of the experimental results. By providing a through hole in the cylinder for the pin to pass through, the present invention can also be used to test the tensile strength of the pin when welded to the inner side of the curved plate. The present invention also facilitates the testing of the tensile strength of multiple pins connected to the curved plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention is described in detail below with reference to specific embodiments and accompanying drawings. To illustrate details and facilitate understanding of its principles, the drawings are not necessarily drawn to scale, and similar reference numerals may describe similar components in different views. The accompanying drawings generally illustrate the embodiments discussed herein by way of example and not limitation. Among them:

[0018] Figure 1 is a schematic diagram of the curved plate located above the lower beam.

[0019] Figure 2 yes Figure 1 Schematic diagram of the AA section.

[0020] Figure 3 It is a schematic diagram of the second embodiment.

[0021] Figure 4 It is a schematic diagram of embodiment three.

[0022] Figure 5 yes Figure 4 Schematic diagram of the BB cross section.

[0023] Figure 6 It is a schematic diagram of embodiment 4.

[0024] In the figure, 1. base; 2. pin; 3. upper crossbeam; 4. upper chuck; 5. curved plate; 6. lifting device; 7. lower crossbeam; 8. connector; 9. end stretching device; 10. guide roller; 11. through hole; 12. sliding connection mechanism. DETAILED DESCRIPTION

[0025] The following are specific embodiments of the present invention, which are further described in conjunction with the accompanying drawings to further illustrate the technical solutions of the present invention. However, the present invention is not limited to these embodiments, and the following embodiments do not limit the inventions involved in the claims. In addition, not all combinations of features described in the embodiments are necessarily required for the solutions of the invention.

[0026] The principle and structure of the present invention are described in detail below with reference to the accompanying drawings and embodiments.

[0027] Example 1

[0028] like Figure 1 、 2 As shown, a pin welding strength testing device includes a tensile testing machine, which includes a base 1 and an upper beam 3 that can move up and down relative to the base 1 for applying an upward pulling force to the pin 2. The upper beam 3 is provided with an upper clamp 4, and also includes an arc-shaped plate 5 welded to the pin 2. The base 1 is provided with a fixing device for fixing the arc-shaped plate 5. One end of the pin 2 is welded to the pin 2, and the upper clamp 4 is used to clamp the other end of the pin 2.

[0029] During testing, the pin is first welded to the curved plate, and then the upper chuck is used to clamp and fix the pin end so that the curved plate end is connected to the curved plate fixing device. The pin is then stretched upward using the upper crossbeam. During the stretching process, the stretched length of the pin and the pulling force of the upper crossbeam on the pin are detected until the weld between the pin and the curved plate is separated. The upper crossbeam 3 is lifted upward relative to the base 1 by the lifting device 6 until the welding position breaks. During this process, the maximum lifting force applied by the lifting device 6 is the maximum tensile force that the welding position can withstand. Of course, in combination with the tensile displacement detection device, a relationship curve between tensile displacement and tensile force can also be obtained. The lifting device 6 can be, for example, a hydraulic cylinder, and the maximum lifting force can be obtained by the hydraulic pressure of the hydraulic cylinder.

[0030] The curved plate 5 has the same outer curved profile as the cooling coil. Furthermore, the curved plate 5 can be made of the same material and thickness as the cooling coil wall. The connection between the pin 2 and the cooling coil is essentially the connection between the pin 2 and the curved surface. Therefore, the strength of the connection between the pin 2 and the curved surface similar to the cooling coil is sufficient.

[0031] The arc plate 5 fixing device includes a lower crossbeam 7 opposite to the upper crossbeam 3, and the two ends of the lower crossbeam 7 are fixedly connected to the base 1 through a connector 8, and the connector 8 can be two metal rods, so that the position of the lower crossbeam 7 is fixed relative to the base 1, and the lower crossbeam 7 has an arc-shaped contour surface for fixing the arc plate 5, so as to keep the contour shape of the arc plate 5 unchanged during stretching, and the cross-section of the lower crossbeam 7 is circular. The lower crossbeam 7 of this embodiment is a cylinder, and the arc length of the arc plate 5 is greater than the arc length of the semicircle of the cross-section of the lower crossbeam 7, so that when the two ends of the arc plate 5 are subjected to tensile forces in the up and down directions, they maintain a certain distance from the cylinder to avoid interference between the two.

[0032] The device also includes an end-tensioning device 9 for controlling the synchronous upward or downward movement of the ends of the curved plate 5. In this embodiment, the tensioning device is a hydraulic cylinder, the cylinder body of which is connected to the base 1, and the piston of which is connected to the ends of the curved plate 5, thereby applying a downward pulling force to the ends of the curved plate 5. During use, the curved plate 5 is buckled onto the lower crossbeam 7 in an arc-shaped, downward-facing manner. That is, the curved plate 5 is positioned above the lower crossbeam 7, with the ends of the curved plate 5 facing downward, and the tensioning device applies a downward pulling force. The end-tensioning device 9 can also provide a certain amount of additional tension to the curved plate 5, thereby applying a certain amount of stress to the curved plate 5, thereby simulating the effect of tension on the pipe wall when a certain pressure is applied to a pipe container such as a cooling coil.

[0033] Furthermore, an arc-shaped contour surface guide roller 10 is provided on the arc-shaped contour surface of the lower cross beam 7 to support the arc-shaped plate 5 so as to reduce friction with the arc-shaped plate 5 .

[0034] Example 2

[0035] like Figure 3 As shown, different from the above embodiment, the lower cross beam 7 is provided with a through hole 11 for the pin 2 to pass through up and down. At this time, the end of the arc plate 5 can be buckled upward on the lower cross beam 7, that is, the arc plate 5 is located below the lower cross beam 7, and the stretching device applies an upward pulling force to the end of the arc plate 5.

[0036] When in use, the pin 2 passes through the through hole 11 and is connected to the upper clamp 4 . In this way, the test device can also be used to detect the tensile strength of the pin 2 when it is welded to the inner side of the arc-shaped plate 5 .

[0037] Example 3

[0038] like Figure 4 、 5 As shown, different from the above embodiment, the cross section of the lower cross beam 7 is semicircular, which can reduce the length of the through hole 11 while not affecting the tensile strength of the detection pin 2 when welded to the inner side of the arc plate 5.

[0039] Furthermore, the two ends of the lower crossbeam 7 are rotatably connected to the connector 8, so that the lower crossbeam 7 can rotate relative to the connector 8, so that the arc-shaped profile of the lower crossbeam 7 faces downward or upward. When it faces downward, the end of the curved plate 5 can be buckled upward on the lower crossbeam 7, that is, the curved plate 5 is located below the lower crossbeam 7, and the tensioning device applies an upward pulling force to the end of the curved plate 5. When it faces upward, the end of the curved plate 5 can be buckled downward on the lower crossbeam 7, that is, the curved plate 5 is located above the lower crossbeam 7, and the tensioning device applies a downward pulling force to the end of the curved plate 5, which is used to test the tensile strength of the pin 2 when it is welded to the outside of the curved plate 5.

[0040] Example 4

[0041] like Figure 6 As shown, unlike the previous embodiment, the curved plate 5 is provided with a plurality of pins 2 along the length of the lower crossbeam 7. The hydraulic cylinder is connected to the base 1 via a sliding connection mechanism 12. The sliding connection mechanism 12 enables the hydraulic cylinder to move along the length of the lower crossbeam 7. The sliding connection mechanism 12 includes a slide groove located on the base 1, and a slider is provided at the bottom of the hydraulic cylinder to slide in connection with the slide groove. By moving the hydraulic cylinder along the length of the lower crossbeam 7, the curved plate 5 is moved, so that different pins 2 on the curved plate 5 correspond to the upper chuck 4, thereby performing tensile tests on different pins 2.

[0042] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described embodiments without departing from the spirit of the present invention or exceeding the scope of the appended claims.

Claims

1. A pin welding strength test device, comprising a tensile testing machine, the tensile testing machine comprising a base and an upper crossbeam movable up and down relative to the base for applying an upward pulling force to the pin, the upper crossbeam being provided with an upper chuck, characterized in that: It also includes an arc-shaped plate welded with the pin, and a fixing device for fixing the arc-shaped plate is provided on the base, one end of the pin is welded to the pin, and the upper clamp is used to clamp the other end of the pin; the arc-shaped plate fixing device includes a lower cross beam, both ends of the lower cross beam are fixedly connected to the base through a connector, the lower cross beam has an arc-shaped contour surface for fixing the arc-shaped plate, and also includes a stretching device for controlling the two ends of the arc-shaped plate to move upward or downward synchronously; the stretching device includes two telescopic cylinders fixed to the base, and the telescopic rods of the two telescopic cylinders are respectively connected to the two ends of the arc plate; several pins are provided on the arc plate along the length direction of the lower cross beam, and the telescopic cylinder is connected to the base through a sliding connection mechanism, and the sliding connection mechanism enables the telescopic cylinder to move along the length direction of the lower cross beam.

2. The pin welding strength testing device according to claim 1, characterized in that: The arc-shaped contour surface of the lower cross beam is provided with an arc-shaped contour surface guide roller for supporting the arc-shaped plate.

3. The pin welding strength testing device according to claim 1, characterized in that: The cross section of the lower cross beam is circular.

4. The pin welding strength testing device according to claim 3, characterized in that: The arc length of the arc-shaped plate is greater than the arc length of the semicircle of the cross section of the lower beam.

5. The pin welding strength testing device according to claim 1, characterized in that: The lower cross beam is provided with a through hole for the pin to pass through.

6. The pin welding strength testing device according to claim 5, characterized in that: The cross section of the lower cross beam is semicircular; both ends of the lower cross beam are rotatably connected to the connector.

7. An experimental method using the pin welding strength test device according to any one of claims 1 to 6, characterized in that: First, the pin is welded to the arc-shaped plate, and then the upper clamp is used to clamp and fix the end of the pin so that the end of the arc-shaped plate is connected to the arc-shaped plate fixing device. The arc-shaped plate is buckled on the lower crossbeam with an arc facing downward. The stretching device provides a certain additional pulling force to the arc-shaped plate, so that the arc-shaped plate has a certain amount of stress. Then, the upper crossbeam is used to stretch the pin upward. During the stretching process, the stretched length of the pin and the pulling force of the upper crossbeam on the pin are detected until the welding point of the pin and the arc-shaped plate is separated.

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