Detachable inclined Y-shaped groove welding crack test device

Abstract

A detachable inclined Y-shaped groove welding crack test device comprises a gap control clamp and a matched test piece, the gap control clamp comprises an outer frame and a window in the middle of the outer frame, a plurality of threaded holes and fastening bolts matched with the threaded holes are symmetrically formed in the two opposite side walls of the window in the length direction of the outer frame, and the matched test piece is movably arranged in the window. The fastening bolt is tightened to restrain the matched test piece, so that the purpose of fixing the test piece is effectively achieved, the root gap of the test weld joint is ensured, and the restraining force is provided; the gap control clamp is high in adaptability to test pieces with different thicknesses and can be repeatedly used, the test pieces are simple and easy to replace, batch operation of inclined Y-shaped groove welding crack tests is achieved, and the time cost of the tests is greatly reduced; meanwhile, compared with the sample size in GB32260.2, the requirement for the size of a test piece is reduced, the material cost is saved, the root gap of the welding seam is well controlled, and the result accuracy is guaranteed.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal material welding, and relates to a method for evaluating the cold crack sensitivity of metal materials, a method for welding crack test of inclined Y-groove under self-restraint with multiple thicknesses and large quantities, and particularly relates to a detachable welding crack test device for inclined Y-groove. Background Art

[0002] The inclined Y-groove welding crack test, also known as the small iron research test, belongs to a self-restraint test and is a qualitative evaluation test for cold cracks in metal material weldments. It is applicable to evaluating the cold crack sensitivity of welding materials, base metals and welded joints of metal materials, especially steel. The earliest national standard GB4675.1 "Weldability Test - Method for Welding Crack Test of Inclined Y-Groove" was issued in 1984 and has been used to guide production practice. With the gradual improvement of China's smelting and rolling steel levels in recent decades, various low-hydrogen type welding consumables and low-alloy high-strength steels have emerged, and the crack resistance of the developed and produced steels has become higher and higher. For this reason, this standard was abolished in 2004, and no alternative standard of the same type appeared. However, a large number of subsequent production practices have shown that the production technologies of steel and welding consumables themselves are only one of the factors affecting the crack sensitivity of materials after welding. Under relatively harsh working conditions, welding cold crack problems will still occur. Therefore, after 11 years without a standard to rely on, GB32260.2 "Destructive Tests on Welds in Metal Materials - Cold Crack Tests on Welded Specimens - Arc Welding Processes - Part 2: Self-Restraint Tests" finally regulated the requirements for welding cold crack tests again in 2015. Compared with the special description of the iron research test in the old standard, the new standard integrates three self-restraint cold crack test methods: CTS (controlled thermal intensity) test, iron research (inclined Y-groove) or Caspian Sea (U-groove) test, to evaluate the cold crack sensitivity of arc welding base metals and welding materials. As a cold crack evaluation method with convenient specimen processing, simple operation, short test cycle and accurate and obvious test results, the inclined Y-groove welding crack test is more favored by researchers and continues to be widely used in laboratory research and engineering.

[0003] The test plate used in the inclined Y-groove welding crack test method is prepared from the material to be welded. X-type grooves are opened at both ends of the test plate to be evaluated, and the restraint welds are welded on both sides; the middle of the test plate is the position of the test weld, and the grooves are different. One side is opened with an X-type symmetric groove, and the other side is opened with an inclined Y-groove. A gap of 2 ± 0.2 mm is reserved between the two butt plates, and a single-pass test weld is welded. After welding, it is placed for 48 h, and the surface and sectional crack rates of the test weld are statistically analyzed. GB32260.2 has clear regulations on the processing dimensions, groove angles, gap dimensions, calculation methods of welding crack rates, etc. of the iron research test plate, and the most prone problem among them is the control of the gap dimension, which directly affects the accuracy of the welding cold crack evaluation results.

[0004] Refer to the requirements of GB32260.2 for the processing of test plates. Usually, wire cutting is used to divide the test plate to be welded into two parts. The X-shaped groove and inclined Y-shaped groove are processed in sections on the two separated test plates, and then they are joined together. First, the restraint weld is welded. Due to the thermal influence during the welding of the restraint weld, there will be a large change in the size of the test plate due to thermal expansion and contraction. This also makes the control of the root gap size of the test weld bead in the later stage a difficult problem. To meet the size requirement of 2±0.2mm for the root gap of the test weld groove in the standard, there are two common ideas: One is to start from the root gap of the test weld groove, that is, methods such as placing a 2mm backing plate at the root of the test weld groove, reserving the test weld gap and welding shrinkage before welding the restraint weld, or changing the size and shape of the test plate to be welded are used to reduce the instability of the gap size caused by the welding of the restraint weld and ensure that the root gap size of the test weld bead is still within the range of 2±0.2mm after the restraint weld is welded. However, this type of method is not smooth in practical applications. Problems such as the backing plate at the root of the test weld cannot be removed due to the restraint stress generated by the welding of the restraint weld, it is difficult to control the welding shrinkage allowance due to different welding processes and materials to be welded, and the change of the test plate shape increases the processing difficulty and workload have successively emerged, and it cannot be used as the optimal method to control the test weld gap. The other is to start from the external device, that is, under the condition of ensuring that the test plate to be welded remains unchanged, the root gap value of the test weld is controlled through the designed external device. However, the use of this external device is limited and there is a certain processing difficulty, and it is difficult to achieve the purpose of a simple test process and accurate test results. The effective implementation of the above two types of methods is very difficult in practical applications. If the root gap of 2±0.2mm of the test weld is too large or too small, it will affect the final evaluation result of the welding crack. There is an urgent need for a new, reliable and simple method to ensure the gap value and guide the development of the inclined Y-shaped groove welding cold crack evaluation test in the future.

[0005] The method for ensuring the groove gap of the test weld in the inclined Y-groove welding crack test disclosed in the patent application with the application number 201910950526.9 mainly designs a dovetail groove rigid restraint block, which is embedded in the X-grooves at both ends of the restraint weld of the test plate to be welded. The restraint weld is directly welded without being removed later. This requires machining twice the number of dovetail restraint blocks as the number of test plates to be welded, which not only increases the workload but also fails to meet the test requirement that the root of the restraint weld needs to be fully penetrated. The patent application with the application number 201611208203.5 discloses an improved inclined Y-groove welding crack sensitivity test specimen and its manufacturing method. It omits the welding of the restraint weld and uses a machining method. A Y-shaped weld groove is directly cut on the test plate to be welded by using an end mill and electric discharge machining, thus effectively ensuring the gap value. However, this method is complex in operation, high in processing cost, time-consuming in batch production, requires high machining accuracy when turning the test plate to machine the groove and the overlapping gap groove, has great difficulty in groove machining, and it is difficult to guarantee the success rate. The utility model patent application with the application number 202222362993.X discloses a weld gap control device for the inclined Y-groove flux welding crack test. It mainly designs a welding plate fixing bracket with a wedge-shaped plug. After the restraint weld is welded, the plug is taken out while completing the gap control, so as to achieve reuse. However, the wedge-shaped plug of this device is fixed on the bottom plate by welding, so it is very difficult to adjust the angle of the wedge-shaped plug to meet the requirements under the influence of welding stress. At the same time, because the fixing bracket of the device is made of a steel plate, during operation, it needs to be buckled on the test plate to be welded and use the wedge-shaped plug to make the gap value meet the requirement of 2 mm. Therefore, despite the bolt fixing position, factors such as frequent replacement and calibration, and the very sharp tip of the wedge-shaped plug make the time cost, test safety and test accuracy of the test not well guaranteed. Therefore, there is an urgent need for a new type of gap control method that is simple in processing, easy in operation and meets the test standard requirements, can ensure the stability of the gap while being reusable, and complete the evaluation of the welding cracks of the batch test welds. Summary of the Invention

[0006] In order to solve the technical problems that occur in the above-mentioned inclined Y-groove welding crack test, the purpose of the present invention is to provide a detachable inclined Y-groove welding crack test device. Aiming at the problems that it is difficult to control the root gap of the test weld groove during the Y-groove test, which seriously affects the test results and progress, etc., it can avoid the welding of the restraint weld while well controlling the root gap value of the test weld groove, meet the various requirements of the standard, and the fixture is detachable and reusable, greatly reducing the processing time and difficulty of the test plate to be welded, simplifying the test operation and effectively improving the accuracy of the inclined Y-groove welding crack test results.

[0007] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0008] A detachable inclined Y-groove welding crack test device, comprising a gap control fixture and a supporting specimen, characterized in that: the gap control fixture includes an outer frame 1 and a window 2 in the middle thereof. Along the length direction of the outer frame 1, a plurality of threaded holes 3 and matching fastening bolts 4 are symmetrically arranged on the two side walls of the window 2 opposite to each other. A supporting specimen is movably arranged in the window 2, and the fastening bolts 4 are loosened and tightened to constrain the supporting specimen.

[0009] The supporting specimen includes a specimen block 7 with a double-edge inclined surface and a specimen block 5 with a single-edge inclined surface. The specimen block 7 with a double-edge inclined surface includes a first back side 7-1, a first edge side 7-2 connected to the first back side 7-1, and a first edge side inclined surface 7-3-1 and a second edge side inclined surface 7-3-2 that are connected to each other on the side opposite to the first back side 7-1. The specimen block 5 with a single-edge inclined surface includes a second back side 5-1 and a second edge side 5-2 connected to the second back side 5-1. The first back side 7-1 of the specimen block 7 with a double-edge inclined surface and the second back side 5-1 of the specimen block 5 with a single-edge inclined surface are respectively attached to the side walls of the window 2, and the first edge side 7-2 of the specimen block 7 with a double-edge inclined surface and the second edge side 5-2 of the specimen block 5 with a single-edge inclined surface are joined to form an inclined Y-groove shape.

[0010] A gap control groove 6 is provided in the middle of the edge surface of the specimen block 5 with a single-edge inclined surface. The angle of the gap control groove 6 and the angle of the second edge side 5-2 of the specimen block 5 with a single-edge inclined surface are both 60°.

[0011] The depth of the gap control groove 6 is 2 ± 0.2 mm.

[0012] The included angle between the first edge side inclined surface 7-3-1 and the second edge side inclined surface 7-3-2 is 120°.

[0013] The shapes and areas of the first edge side inclined surface 7-3-1 and the second edge side inclined surface 7-3-2 are equal.

[0014] The threaded holes 3 are symmetrically and equidistantly distributed on both sides along the length direction of the outer frame 1 of the fixture, with 3 to 5 on each side, and the interval distance between the threaded holes 3 on one side is 25 - 60 mm.

[0015] The fastening bolts 4 are hexagon head full thread, with a length between 35 - 45 mm, and the dimensions comply with the regulations in GB5781-2016.

[0016] An inclined Y-groove welding crack test fixture and a manufacturing method of a supporting test specimen provided by the present invention include: a fixture outer frame, threaded holes, hexagon head fully threaded fastening bolts, and a supporting test specimen. The fixture outer frame is obtained by cutting a rectangular window at the center of a whole test plate, and is drilled with threaded holes, which are used in combination with the hexagon head fully threaded fastening bolts to fix the test specimen to be welded; when processing the supporting test specimen on the single-edge inclined surface side, a groove with a depth of 2 ± 0.2 mm is processed at the middle position for controlling the gap of the test weld.

[0017] Compared with the prior art, the present invention has the following technical effects:

[0018] 1. The thicknesses of the fixture outer frame and the test specimen can be adjusted, and the fixture outer frame can be reused. The thickness difference between the fixture outer frame and the test specimen does not limit their adaptability, improving the test efficiency.

[0019] 2. The test specimen of the present invention is composed of two parts: a specimen block with a single-edge inclined surface and a specimen block with a double-edge inclined surface. Compared with the methods of welding restraint welds and controlling gaps by adding gaskets in other prior arts, the restraint welds are removed, and bolts are used to provide restraint. The groove on the single-inclined surface test specimen can also accurately control the gap value.

[0020] 3. The device is detachable and easy to process. Different from the prior art which can only be processed by a milling machine with complex operations, the test specimen of the present invention can be made by wire cutting or other machining methods (milling machine processing, planer processing) as long as the single-edge and double-edge inclined surfaces of the two parts of the test specimen can be processed. The processing method is not unique. The present invention has stronger applicability.

[0021] 4. The fixture outer frame and the test specimen of the present invention can be made of different materials. The main function of the fixture outer frame is to replace the restraint weld in GB32260.2, control the gap, and provide restraint. In the present invention, the bolts of the fixture outer frame provide restraint, and the groove on the test specimen controls the gap. Therefore, the outer frame and the test specimen do not need to be of the same nature, reducing the requirements for the size of the test specimen, saving test materials, and improving the test efficiency.

[0022] In summary, the present invention ingeniously omits the welding step of the restraint weld, and uses the fixture and the externally added hexagon head fully threaded fastening bolts to provide restraint force and fix the test plate to complete the evaluation of welding cracks. The fixture is simple to disassemble; the welding process of the restraint weld is removed, and a gap control groove is processed in the middle of the test specimen. With the cooperation of the externally added bolt restraint, the weld gap is effectively controlled, and the process of replacing and manufacturing the specimen is smoother and time-saving. It is suitable for batch tests, accurately controls the gap size while meeting the standard test requirements, achieving the purpose of ensuring the test results and simplifying the test process. Description of the Drawings

[0023] To more clearly show the actual assembly of each component of the present invention and illustrate its innovative points, a specific-sized fixture will be selected as an example for the demonstration of the embodiments below. It will be compared with the test specimens in GB32260.2 "Destructive tests on welds in metallic materials - Cold cracking tests for weldments - Arc welding processes - Part 2: Self-restraint tests", and a brief introduction to the drawings required in the embodiments will be given. For those of ordinary skill in the art, without creative efforts, various other drawings with dimensional modifications or proportional adjustments in other situations can also be obtained based on these drawings.

[0024] Figure 1 It is a schematic diagram of a bevel Y-groove welded crack test specimen in GB32260.2. Among them, Figure 1 (a) is a top view of the test specimen required by the standard, Figure 1 (b) is a sectional view of the test specimen A-A, Figure 1 (c) is a sectional view of the test specimen B-B.

[0025] Figure 2 It is a schematic diagram of a fully threaded hexagon head bolt.

[0026] Figure 3 It is a schematic diagram of the fixture outer frame obtained by wire electrical discharge machining of the whole test plate material at the central position.

[0027] Figure 4 It is a schematic sectional view of the fixture outer frame after machining the threaded holes.

[0028] Figure 5 It is a schematic diagram of the structure of the detachable bevel Y-groove welded crack test gap control fixture of the present invention.

[0029] Figure 6 It is a schematic diagram of the test specimen of the specimen block with a double-edged bevel and the specimen block with a single-edged bevel with a gap control groove. Among them, Figure 6 (a) is a schematic diagram of the specimen block with a double-edged bevel of the test specimen, Figure 6 (b) is a schematic diagram of the specimen block with a single-edged bevel with a gap control groove of the test specimen.

[0030] Figure 7 It is a schematic diagram of the bevel Y-groove test specimen supporting the present invention.

[0031] Figure 8 It is a sectional view of the bevel Y-groove test specimen supporting the present invention. Among them, Figure 8 (a) is a sectional view at the middle position in the length direction of the test specimen, Figure 8 (b) is a top view of the test specimen.

[0032] Figure 9This is an overall assembly schematic diagram of the detachable inclined Y-groove welding crack test gap control fixture and the test specimen of the present invention.

[0033] Figure 10 This is a schematic cross-sectional view after the overall assembly of the detachable inclined Y-groove welding crack test gap control fixture and the test specimen of the present invention. Among them, Figure 10 (a) is a cross-sectional view at the middle position in the length direction after the overall assembly, Figure 10 (b) is a top view of the fixture and the test specimen after the assembly is completed.

[0034] Among them, 1. Fixture outer frame; 2. Electric spark cutting window; 3. Threaded hole; 4. Fastening bolt; 5. Specimen block with single-edge bevel; 5-1. Second back side; 5-2. Second edge side; 6. Gap control groove; 7. Specimen block with double-edge bevel; 7-1. First back side; 7-2. First edge side; 7-3-1. First edge side bevel; 7-3-2. Second edge side bevel. Specific implementation manner

[0035] The following will further clearly and completely describe the present invention with reference to the accompanying drawings. It should be noted that the following described embodiments only represent a certain situation in actual application, rather than all embodiments. Based on the embodiments to be described of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative labor shall fall within the protection scope of the present invention.

[0036] A detachable inclined Y-groove welding crack test device includes a gap control fixture and a supporting specimen. The gap control fixture includes an outer frame 1 and a window 2 in the middle thereof. On the opposite side walls in the length direction of the outer frame 1 and symmetrically arranged on both sides of the window 2 are a plurality of threaded holes 3 and corresponding fastening bolts 4. A supporting specimen is movably arranged in the window 2. By loosening and tightening the fastening bolts 4, the supporting specimen is constrained, effectively achieving the purpose of fixing the test specimen, ensuring the root gap of the test weld and providing restraint force.

[0037] The matching test piece includes a test piece block 7 with a double-edged bevel and a test piece block 5 with a single-edged bevel. The test piece block 7 with a double-edged bevel includes a first back side 7-1, a first edge side 7-2 connected to the first back side 7-1, and a first edge side bevel 7-3-1 and a second edge side bevel 7-3-2 connected to each other on the side opposite to the first back side 7-1. The test piece block 5 with a single-edged bevel includes a second back side 5-1 and a second edge side 5-2 connected to the second back side 5-1. The first back side 7-1 of the test piece block 7 with a double-edged bevel and the test piece block 5 with a single-edged bevel are The second back side 5-1 of the block 5 is respectively fitted with the side wall surface of the window 2, and the first edge side 7-2 of the double-edged beveled specimen block 7 and the second edge side 5-2 of the single-edged beveled specimen block 5 are assembled to form an oblique Y-shaped groove; the test specimen consists of a double-edged beveled specimen block 7 and a single-edged beveled specimen block 5 with a gap control groove 6. Compared with the design of the test plate in GB32260.2, the restrained weld part is omitted, the test cycle and material cost are reduced, and the root gap of the test weld can be effectively controlled at 2±0.2mm.

[0038] A gap control groove 6 is provided in the middle of the blade surface of the single-edged inclined surface specimen block 5 , and the angle of the gap control groove 6 and the angle of the second blade side 5 - 2 of the single-edged inclined surface specimen block 5 are both 60°.

[0039] The depth of the gap control groove 6 is 2±0.2 mm.

[0040] The included angle between the first blade side bevel 7-3-1 and the second blade side bevel 7-3-2 is 120°.

[0041] The first blade side bevel 7-3-1 and the second blade side bevel 7-3-2 are equal in shape and area.

[0042] The threaded holes 3 are symmetrically and equidistantly distributed on both sides of the length direction of the outer frame 1 of the clamp, with 3 to 5 threads on each side, and the interval between the threaded holes 3 on one side is 25-60 mm.

[0043] The fastening bolt 4 has a hexagonal head with full thread, a length between 35-45 mm, and a size that complies with the provisions of GB5781-2016.

[0044] like Figures 1 to 5 As shown, the gap control fixture mainly includes two parts: the fixture outer frame 1 and the hexagonal head full-threaded fastening bolt 4. The fixture outer frame 1 is obtained by cutting the window 2 from the complete test plate material by electric spark cutting, and the full-threaded through holes 3 are processed on both sides of the length direction of the fixture outer frame. The material used for the hexagonal head full-threaded bolt is as consistent as possible with the fixture outer frame 1 and is compatible with the threaded hole. Compared with the requirements for the inclined Y groove welding crack test specimen in GB32260.2 (such as Figure 1As shown in the figure, the present invention can eliminate the welding of the restraint weld, and only need to process the test specimens required for the test weld. Among them, the specimen block 7 with a double-edge bevel and the specimen block with a single-edge bevel with a gap control groove 6 are as follows Figure 6 As shown, the schematic diagram of the two-part test specimen fitting together is as follows Figure 7 As shown; then refer to Figure 8 As shown in the method, clamp the test specimen. Tighten the hexagon socket full thread fastening bolts 4 on both sides in the length direction of the outer frame of the fixture, so that the specimen block 7 with a double-edge bevel fits tightly with the grooves 6 on both sides of the specimen block with a single-edge bevel, and ensure that the test gap meets the requirement of 2±0.2 mm in GB32260.2, then the welding of the test weld can be carried out smoothly.

[0045] In the described embodiment, as Figure 9 As shown, this detachable inclined Y-groove welding crack test gap control fixture includes a fixture outer frame 1, six threaded holes 3 and six hexagon socket full thread fastening bolts 4 are symmetrically distributed at equal distances in the length direction of the cut window. The six fastening bolts 4 can fix the test specimen and supplement the required restraint force to prevent the test specimen from loosening and control the gap size. Among them, the length, width and thickness dimensions of the original test plate and the window cut in the fixture outer frame 1 can be flexibly adjusted according to the specimen to be welded, and the corresponding threaded holes 3 and fastening bolts 4 can also be adjusted accordingly to make them fit; the supporting test specimen includes two parts, namely the specimen block 7 with a double-edge bevel and the specimen block 5 with a single-edge bevel with a gap control groove 6. According to the gap requirement of the test weld of the inclined Y-groove welding crack test specimen in GB32260.2, the depth of the gap control groove of the specimen block with a single-edge bevel of the supporting test specimen must be controlled within the range of 2±0.2 mm (here the groove depth is relative to the single-edge surface of the inclined Y-groove, that is, the vertical distance between the two parallel surfaces is 2±0.2 mm).

[0046] The following is a detailed description of the manufacturing process of this detachable inclined Y-groove welding crack test gap control fixture 001:

[0047] Step 1: Select a steel plate for cutting the original test plate. The length of the original test plate is 200 mm, the width is 150 mm, and the thickness is 30 mm.

[0048] Step 2: At the center position of the original test plate, use electric spark cutting to cut out a fixture window 2 with a length of 120 mm and a width of 90 mm to obtain the fixture outer frame 1.

[0049] Step 3: Process threaded holes 3 symmetrically and at equal distances on both sides in the length direction of the fixture outer frame 1. The interval distance of the threaded holes 3 on one side is 30 mm, and the size of the threaded holes 3 is M10×1.25.

[0050] Step 4. On the basis of Step 3, process the hexagon head fully threaded fastening bolt 4. The size of the fastening bolt 4 is M10×1.25, and the length is between 35 - 45 mm. The size design refers to the regulations in GB5781 - 2016.

[0051] Step 5. Process the test specimen. According to the size of the fixture window 2 cut out in Step 2 and combined with the requirement in GB32260.2 that the length of the test weld is 80 mm, determine that the length of the test plate is between 100 - 110 mm and the width is 86 - 88 mm.

[0052] Step 6. On the basis of Step 5, process the test specimen in two parts. First, the specimen block 7 with a double - edged bevel: Use wire electrical discharge machining to cut in at the middle position in the width direction of the test plate. Rotate the cutting wire clockwise at an angle of 30° with the vertical direction and cut the test plate into two parts along the length direction. Select one of them, and then rotate the cutting wire counterclockwise at an angle of 30° with the vertical direction to process the specimen block with a double - edged bevel. Then process the specimen block 5 with a single - edged bevel with a gap - control groove 6: Select the other part of the specimen, move the cutting wire to the middle position in the length direction, rotate the cutting wire clockwise at an angle of 30° with the perpendicular direction to make it parallel to the specimen block with a single - edged bevel, and cut in perpendicular to the length direction. The cutting depth must be 2±0.2 mm (this is to meet the requirement for the test weld gap in GB32260.2). Then, taking this position as the reference, symmetrically cut out an 80 - mm test weld area along the length direction, and finally move the cutting wire out from the side of the specimen block with a single - edged bevel perpendicular to the length direction to complete the processing of the test specimen. It should be noted that the bevel angles described in Step 6 must be designed with reference to the angles given in GB32260.2, as Figure 1 shown, so as to control the root gap of the weld groove while meeting the requirement for the length of the test weld in the standard and eliminating the welding process of the restraint weld.

[0053] As Figure 10 , the usage process of the detachable inclined Y - groove welding crack test gap - control fixture and the supporting test specimen is as follows:

[0054] Step 1. Conduct an inclined Y - groove welding crack test for a certain steel type. Select this steel and make this detachable inclined Y - groove welding crack test gap - control fixture and the corresponding test specimen with reference to the production process of the detachable inclined Y - groove welding crack test gap - control fixture.

[0055] Step 2. Place the fabricated test specimen on the gap - control fixture, making the lower half of the specimen block with a double - edged bevel of the specimen closely fit the protruding positions at both ends of the specimen block with a single - edged bevel to ensure the gap control in the middle position.

[0056] Step 3: Tighten the fastening bolts 4 on both sides to fix the position of the test specimen, so that the test specimen is tightly and firmly installed together with the fixture, providing a restraint force to ensure good control of the gap. Thus, the clamping of the specimen is completed.

[0057] Step 4: According to the test requirements, weld a single-pass weld with a length of 80 mm on the test specimen, and then carry out the subsequent welding crack evaluation work in sequence.

[0058] Through the detailed description of the manufacturing process and use process of the detachable inclined Y-groove welding crack test gap control fixture and the supporting test specimen for specific embodiments, it can be seen that compared with the requirements for the inclined Y-groove welding crack test plate in the standard, as Figure 1 shown, this gap control fixture omits the welding step of the restraint weld, and provides the restraint force required by the standard in the way of fixing with fastening bolts, thereby avoiding the instability of the gap size caused by the welding heat influence and effectively solving the problem of gap control; this fixture has a large allowable range for the thickness of the test specimen. As long as the thickness of the test specimen is greater than the diameter of the fastening bolt and less than or equal to the thickness of the outer frame of the fixture, the same outer frame of the fixture can be reused, greatly saving the material cost; at the same time, the control device of this fixture and the processing of the required test specimen are simple, the clamping is convenient, and the disassembly and replacement of the specimen after welding are simple and easy to operate, providing great convenience for batch welding crack evaluation, and greatly shortening the test cycle and time cost. Therefore, the detachable inclined Y-groove welding crack test gap control fixture is a new type of welding crack evaluation gap control device with accurate groove gap control, flexible adaptation to different welding crack evaluation requirements, and accurate and reliable results.

[0059] In the present invention, specific examples are used to elaborate in detail the principle and implementation manner of a manufacturing method for an inclined Y-groove welding crack test fixture and a supporting test specimen. It should be noted that the description of the above embodiments is only used to help understand the core idea of the present invention; for those of ordinary skill in the art, on the basis of referring to the design idea of the embodiment of this gap control fixture, changes and extensions will occur in the specific fixture dimensions, application scenarios, and application scopes, and these situations all belong to the scope involved in the present invention. To sum up, the content of this specification aims to elaborate the design method and concept of a manufacturing method for an inclined Y-groove welding crack test fixture and a supporting test specimen, and should not be construed as a limitation of the present invention.

Claims

1. A detachable inclined Y-groove welding crack test device, comprising a gap control fixture and a matching test piece, characterized in that: The gap control fixture comprises an outer frame (1) and a window (2) in the middle thereof. A plurality of threaded holes (3) and corresponding fastening bolts (4) are symmetrically arranged on the longitudinal direction of the outer frame (1) and on the two opposite side walls of the window (2). A matching test piece is movably arranged in the window (2), and the fastening bolts (4) are loosened to constrain the matching test piece.

2. A detachable oblique Y-shaped groove welding crack test device according to claim 1, characterized in that: The matching test piece comprises a test piece block (7) with a double-edged bevel and a test piece block (5) with a single-edged bevel. The test piece block 7 with a double-edged bevel comprises a first back side (7-1), a first edge side (7-2) connected to the first back side (7-1), and a first edge side bevel (7-3-1) and a second edge side bevel (7-3-2) connected to each other on a side opposite to the first back side (7-1). The test piece block (5) with a single-edged bevel comprises a first back side (7-1), a first edge side (7-2) connected to the first back side (7-1), and a first edge side bevel (7-3-1) and a second edge side bevel (7-3-2) connected to each other on a side opposite to the first back side (7-1). The first back side (7-1) of the double-edged beveled specimen block (7) and the second back side (5-1) of the single-edged beveled specimen block (5) are respectively fitted with the side wall surface of the window (2); the first edge side (7-2) of the double-edged beveled specimen block (7) and the second edge side (5-2) of the single-edged beveled specimen block (5) are combined to form an oblique Y-shaped groove.

3. A detachable oblique Y-shaped groove welding crack test device according to claim 2, characterized in that: A gap control groove (6) is provided in the middle of the blade surface of the single-edged inclined surface specimen block (5), and the angle of the gap control groove (6) and the angle of the second blade side (5-2) of the single-edged inclined surface specimen block 5 are both 60 degrees.

4. A detachable oblique Y-shaped groove welding crack test device according to claim 3, characterized in that: The depth of the gap control groove (6) is 2±0.2 mm.

5. A detachable oblique Y-shaped groove welding crack test device according to claim 2, characterized in that: The included angle between the first blade side bevel (7-3-1) and the second blade side bevel (7-3-2) is 120°.

6. A detachable oblique Y-shaped groove welding crack test device according to claim 2 or 5, characterized in that: The first blade side bevel (7-3-1) and the second blade side bevel (7-3-2) are equal in shape and area.

7. A detachable inclined Y-shaped groove welding crack test device according to claim 1, characterized in that: The threaded holes (3) are symmetrically and equidistantly distributed on both sides of the length direction of the outer frame (1) of the clamp, with 3 to 5 threads on each side, and the spacing between the threaded holes (3) on one side is 25 to 60 mm.

8. The detachable inclined Y-shaped groove welding crack test device according to claim 1, characterized in that: The fastening bolt (4) has a hexagonal head with full thread and a length between 35 and 45 mm.

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