A method for manufacturing a partially composite explosive welding clad plate

Abstract

The present application belongs to the technical field of explosive welding, and specifically discloses a preparation method of a locally-composited explosive welding composite plate. A slope and a blunt edge are formed at the edge of the pre-combination surface of a cladding plate, and a stress groove is arranged on the back surface of the pre-combination surface of the cladding plate, so as to obtain a cladding plate for a locally-composited explosive welding composite plate; then, the treated cladding plate is subjected to explosive welding with a base plate, so as to obtain a locally-composited explosive welding composite plate; wherein, the explosive welding is performed in an extended charging mode. The preparation method of the locally-composited explosive welding composite plate can directly complete the local explosive composition of the cladding plate in the composite area of the composite plate through reasonable charging structure and process control, and does not need subsequent removal processing, so that the material can be effectively saved, the construction period can be shortened, and the cost can be reduced.

Description

Technical Field

[0001] This invention relates to the field of explosive welding technology, and in particular to a method for preparing a partially composite explosively welded composite plate. Background Technology

[0002] Explosive welding is a special welding method that uses the energy of explosives to achieve metallurgical bonding between dissimilar materials. Composite tube sheets produced using explosive welding combine strength, corrosion resistance, and good weldability, and are widely used in petroleum, chemical, and pharmaceutical industries. In practical engineering applications, users may require only localized areas of the composite plate to be laminated with non-ferrous metals, leaving the carbon steel substrate exposed in the remaining areas, depending on different structural and installation requirements. For such requirements, existing technologies typically employ an overall explosive lamination method, where the entire substrate surface is laminated with non-ferrous metals, and then the cladding in the unwanted areas is removed by machining or grinding to expose the substrate. While this "laminate first, remove later" processing method achieves the effect of localized lamination, it results in a significant waste of precious metal materials, increases processing steps and labor costs, and prolongs the production cycle, which is inconsistent with the development direction of green manufacturing and cost reduction and efficiency improvement. Publicly available patents disclose explosive bonding methods using a support member to connect a metal loading plate. The method involves placing explosives above the metal loading plate and connecting a cover plate below. After detonation, the detonation drives the metal loading plate, which then pushes the cover plate to tilt and collide with the substrate at high speed, thus achieving bonding of the two metals. Theoretically, this method can mitigate boundary effects to some extent, avoiding non-bonding defects at the edges of the bonding area. However, this method is only suitable for the preparation of test plates or small-area composite plates. This is because it is difficult to achieve absolute flatness between the loading plate and the cover plate; a certain gap is unavoidable. Since the explosives are placed above the loading plate, this gap affects the tilting and collision state of the cover plate at the moment of detonation, thus adversely affecting the bonding quality of the bonding area. This effect is particularly significant in the actual production of large-format, thick composite plates requiring local bonding. In addition, some processes directly use non-ferrous metal cladding plates smaller than the substrate size for explosive bonding in the areas where bonding is required. This process cannot avoid boundary effects and may even result in large areas of non-bonding at the edges. The thicker the cladding plate, the greater the boundary effect. At the same time, it can cause internal damage to the substrate at the tilted collision position of the cladding plate edge, such as the initiation of microcracks in weak microstructures like grain boundaries. It may also lead to internal delamination of carbon steel plates, which can greatly affect product quality and in severe cases, even lead to scrapping.

[0003] Therefore, how to provide a method for preparing a locally composite explosively welded composite plate, which can directly complete the local explosive bonding of the cladding in the area where the composite plate needs to be composited, avoids subsequent removal processing operations, effectively saves materials, shortens the construction period, and reduces costs is an urgent problem to be solved in this field. Summary of the Invention

[0004] In view of this, the present invention provides a method for preparing a partially composite explosively welded composite plate to solve the problems of complex process, large limitations and poor bonding when the existing partially composite plates are prepared by explosive welding.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for preparing a partially composite explosively welded composite plate includes the following steps: 1) A bevel and blunt edge are formed at the edge of the pre-bonding surface of the cover plate, and a stress groove is set on the back of the pre-bonding surface of the cover plate to obtain a cover plate for explosive welding composite plate with local composite structure. 2) The partially composite exploded welded composite plate is explosively welded to the substrate using a cover plate to obtain a partially composite exploded welded composite plate; The explosive loading method for the explosive welding is an extended charge.

[0006] Preferably, the angle between the slope and the pre-bonded surface in step 1) is 155~172°, and the size of the blunt edge is ≤1 / 2 of the thickness of the cover plate and not greater than 4mm.

[0007] Preferably, the orthographic projection of the centerline of the stress groove onto the pre-bonded surface coincides with the top of the slope. The width of the stress groove is 2~5mm, and the depth is ≥1 / 2 of the thickness of the cover plate.

[0008] Preferably, in step 2), the explosive welding of the partially composite explosive welding composite plate is arranged parallel to the substrate, and the orthogonal projection of the partially composite explosive welding composite plate on the substrate is the partially composite area.

[0009] Preferably, the projected area of ​​the extended charge in the direction of the cover plate of the locally composite explosive welded composite plate is greater than the area of ​​the cover plate of the locally composite explosive welded composite plate. The extension length of the extended charge is 10~15mm.

[0010] Preferably, the explosive loading in the explosive welding includes a central explosive loading area and an edge explosive loading area; In the case of locally composite explosively welded composite plates, the area corresponding to the orthographic projection of the non-slope position of the cladding plate is the central explosive loading area; the area corresponding to the orthographic projection of the slope position is the edge explosive loading area. The explosive loading height in the central explosive loading area is 30~95mm; The explosive loading height in the edge explosive loading area gradually decreases from the center to the periphery, with the minimum explosive loading height in the edge explosive loading area decreasing to 88-92% of that in the central explosive loading area.

[0011] Preferably, when the composite area of ​​the partially composite explosively welded composite plate is located at the edge of the substrate, the detonation point is set at the edge. When the composite area of ​​the partially composite explosively welded composite plate is located at the center of the substrate, the detonation point is set as the geometric center of the cover plate of the partially composite explosively welded composite plate.

[0012] As can be seen from the above technical solution, compared with the prior art, the present invention has the following beneficial effects: 1. When manufacturing a partially composite explosively welded composite plate using the method provided by this invention, it is only necessary to accurately feed materials according to the actual size of the required composite area. Unlike traditional processes, it is not necessary to fully composite the entire composite plate and then perform secondary processing to remove excess coatings. This avoids a large amount of material waste from the source and effectively reduces raw material costs. At the same time, it eliminates redundant post-processing steps, significantly shortens the overall production cycle, and improves manufacturing efficiency.

[0013] 2. The present invention has a simple operation process, easy-to-control process parameters, strong on-site implementation, and can be stably applied to the industrial mass production of large-format and thick composite panels with partial composite. It has good engineering adaptability and broad application prospects.

[0014] 3. By combining multiple technical means such as edge bevel treatment, back stress groove design and extended charge on the cladding plate, this invention can significantly weaken the boundary effect during the explosive bonding process and effectively improve the bonding rate between the cladding plate and the substrate. At the same time, this combined design can effectively alleviate and avoid the impact damage to the inside of the substrate caused by tilting collisions at the edge of the cladding plate, ensuring the structural integrity of the substrate body, thereby improving the quality and reliability of the final product. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0016] Figure 1 This is a cross-sectional schematic diagram of the cover plate for the partially composite explosively welded composite plate prepared in Embodiment 1 of the present invention; Figure 2 This is a partial composite schematic diagram of Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the explosive welding installation in Embodiment 1 of the present invention; Figure 4 This is a partial composite schematic diagram of Embodiment 2 of the present invention. Detailed Implementation

[0017] This invention provides a method for preparing a partially composite explosively welded composite plate, comprising the following steps: 1) A bevel and blunt edge are formed at the edge of the pre-bonding surface of the cover plate, and a stress groove is set on the back of the pre-bonding surface of the cover plate to obtain a cover plate for explosive welding composite plate with local composite structure. 2) The partially composite explosively welded composite plate is explosively welded to the substrate using a cover plate to obtain the partially composite explosively welded composite plate.

[0018] In this invention, the angle between the slope and the pre-bonded surface in step 1) is 155~172°, specifically 156°, 158°, 160°, 162°, 165°, 168°, or 170°; the size of the blunt edge is ≤ 1 / 2 of the thickness of the cover plate and not greater than 4mm, specifically 0.1mm, 0.5mm, 1mm, 2mm, or 3mm.

[0019] In this invention, the slope is the inclined surface after the cover plate is chamfered, and the blunt edge is the remaining part after the cover plate is chamfered in the thickness direction.

[0020] In this invention, the orthographic projection of the centerline of the stress groove onto the pre-bonding surface coincides with the top of the slope; the centerline of the stress groove is the line connecting the centers of each section of the stress groove, and the top of the slope is the intersection line between the slope and the pre-bonding surface of the cover plate.

[0021] In this invention, the width of the stress groove is 2~5mm, specifically 2.5mm, 3mm, 3.5mm, 4mm, or 4.5mm; the depth is ≥ 1 / 2 of the thickness of the cover plate and < the thickness of the cover plate, specifically 2 / 3, 3 / 4, 3 / 5, or 4 / 5 of the thickness of the cover plate.

[0022] In this invention, the stress groove is set around the perimeter, and the stress groove exists at the corresponding position at the top of the slope.

[0023] In this invention, in step 2), the explosive welding of the partially composite explosive welding composite plate is arranged parallel to the substrate, and the orthogonal projection of the partially composite explosive welding composite plate on the substrate is the partially composite area.

[0024] In this invention, the explosive loading method for explosive welding is extended loading.

[0025] In this invention, the extended charge is defined as explosive whose projected area in the direction of the cover plate of the locally composite explosive welded composite plate is greater than the area of ​​the cover plate of the locally composite explosive welded composite plate; the extension of the extended charge is 10~15mm, specifically 11mm, 12mm, 13mm, or 14mm; the extension refers to the fact that the projected shape of the explosive is similar to the projected shape of the cover plate, and is longer than the projected shape of the cover plate in each direction, i.e., the extension.

[0026] In this invention, the explosive loading in the explosive welding includes a central explosive loading area and an edge explosive loading area. The area corresponding to the orthographic projection of the non-slope position of the cover plate of the locally composite explosive welded plate is the central explosive loading area; the area corresponding to the orthographic projection of the slope position is the edge explosive loading area; that is, the area enclosed by the top of the slope is the central explosive loading area, and the area outside is the edge explosive loading area.

[0027] In this invention, the explosive loading height of the central explosive loading area is 30-95mm, specifically 35mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 70mm, 75mm, 80mm, 85mm, and 90mm; the explosive loading height of the edge explosive loading area gradually decreases from the loading height of the central explosive loading area to the surrounding areas, until the explosive loading height of the outermost edge is 88-92% of that of the central explosive loading area, specifically 88.5%, 89%, 89.5%, 90%, 90.5%, 91%, and 91.5%.

[0028] In this invention, the stress groove design and its combination with the extended charge structure are also applicable to the fabrication process of thick-coated composite plates, effectively ensuring edge bonding quality and avoiding excessive material allowance due to edge defects. This technical solution significantly saves material costs while ensuring product quality. Furthermore, based on this method, even more beneficial effects can be achieved by adjusting or adding other process steps, demonstrating good process scalability and adaptability.

[0029] In this invention, when the composite area of ​​the partially composite explosively welded composite plate is located at the edge of the substrate, the detonation point is set at the edge to avoid the phenomenon of non-adhesion of the detonator area; when the composite area of ​​the partially composite explosively welded composite plate is located in the middle of the substrate, the detonation point is set at the geometric center of the cover plate of the partially composite explosively welded composite plate to minimize the detonation propagation distance and form a small wave-shaped bond at the bonding interface, resulting in high bonding strength.

[0030] In this invention, after the explosive welding is completed, processes such as heat treatment, leveling, cutting, and polishing are also included. The locally composite explosively welded composite plate prepared by this invention has thickness differences, requiring local leveling using a hydraulic press; the use of roller leveling machines is strictly prohibited.

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Example 1

[0033] The explosion-proof composite plate S39042+Q345R used in the quench water filter of a domestic coal-to-olefins project has a specification of (6mm+80mm). 3200mm 5250mm, the part requiring composite non-ferrous metals in the product design is only the middle 2500mm. A 4000mm region was successfully prepared using the local composite method disclosed in this invention, as detailed below: 1. Feed materials according to process requirements; substrate size is 80mm. 3200mm 5250mm, cover plate size is 6mm 2550mm 4050mm (If using traditional whole-board composite feeding process, the feeding size of the cladding board is 6mm) 3250mm 5300mm, this method saves about 33.1% of raw materials from the source. The pre-bonding surfaces of the substrate and the cover plate are polished to remove the oxide scale and expose the metallic luster for later use. 2. Using the geometric center of the cladding as a reference point, determine the corresponding dimensional boundary of the substrate to be laminated with non-ferrous metals, which is 2500mm. 4000mm, grind out a slope outside the dimension boundary (angle with the pre-bonding surface is 172°), leaving a 2mm blunt edge at the bottom of the slope, the slope surface is relatively regular and uniform; then turn the cover plate over, and use the same method to determine the size of the substrate to be laminated with non-ferrous metals, use an abrasive wheel to cut a stress groove around the dimension line (the center line of the stress groove on the pre-bonding surface coincides with the top of the slope), the groove depth is 4mm, the groove width is 2mm, to obtain the partially laminated explosive welded composite plate cover plate for later use, its cross-sectional schematic diagram is as follows. Figure 1 As shown; 3. Place the prepared substrate horizontally on a suitable bonding bed that is free of hard foreign objects. After cleaning the area to be bonded, arrange the substrates according to the process requirements, with a spacing of 12mm (the spacing height is calculated using the empirical formula H=K). (δ1+δ2), where K is a coefficient, ranging from 0.1 to 0.3, δ1 is the thickness of the cladding plate, and δ2 is the thickness of the substrate), and then the cladding plate is placed horizontally so that the geometric center of the cladding plate and the substrate are aligned (as shown in the partial composite schematic diagram). Figure 2 As shown, Figure 2 The shaded area is the local composite area, and the dot is the detonation point. The top of the slope and the stress groove on the back of the cladding plate are exactly corresponding to the boundary to be composited. Then, an L-shaped explosive frame is set around the upper surface of the cladding plate, so that the bottom edge of the L-shaped explosive frame extends 15mm beyond the edge of the cladding plate, and the vertical edge of the explosive frame is fixed perpendicular to the cladding plate. 4. Evenly spread the prepared explosive welding-specific explosive onto the covering plate, level it with a special tool, and adjust the charge height to the designed charge height of 45±2mm. Then, manually reduce the explosive height from the stress groove to the edge of the explosive frame (slope location), gradually decreasing it by approximately 9% to 41mm. Next, set the detonation point at the geometric center of the charge placement area, vertically insert the digital electronic detonator, and connect the detonator leads; the installation diagram is shown below. Figure 3 As shown; 5. Detonating the detonator and explosive yields a partially bonded S39042 composite tube sheet. Ultrasonic non-destructive testing is performed according to NB / T47013.3-2023, confirming 100% bonding except at the detonation point. The unbonded area at the detonator point is approximately [missing information]. The thickness of the weld is 30mm, which does not meet the Class B1 requirement in NB / T47002.1-2019. Therefore, a certified welder must perform repair welding according to the qualified welding process specified in NB / T47014. After repair welding, ultrasonic non-destructive testing and penetrant testing are performed. The penetrant testing results meet Class I requirements specified in NB / T47013.5. Subsequently, after heat treatment, leveling, cutting, and grinding, a S39042+Q345R composite plate with a central composite of S39042 non-ferrous metal is obtained, with dimensions of (6mm + 80mm). 3200mm 5250mm, the non-ferrous metal composite area is 2500mm. 4000mm. Testing showed that the composite area met the requirements of NB / T 47002.1-2019 B1 grade, with a shear strength of 296MPa, exceeding the ≥210MPa requirement in the composite standard. Ultrasonic non-destructive testing was performed at the boundary between the composite area and the exposed carbon steel area, and no internal defects were found in the carbon steel.

[0034] Example 2

[0035] A domestic petrochemical equipment project uses explosion-proof composite steel plate S32168+Q345R with dimensions of (5mm+56mm). 2920mm The length is 3800mm, but due to equipment installation requirements, only 2920mm of the section needs to be incorporating non-ferrous metals. 2800mm, with the remaining portion being exposed carbon steel for welding and mounting components, was successfully fabricated using the local composite method disclosed in this invention, as detailed below: 1. Feed materials according to process requirements; substrate size is 56mm. 2960mm 3820mm, cover plate size is 5mm 3000mm 2840mm (If using traditional whole-board composite feeding process, the feeding size of the cladding board is 5mm) 3000mm 3860mm, this method saves about 26.4% of raw materials from the source. The pre-bonding surfaces of the substrate and the cover plate are polished to remove the oxide scale and expose the metallic luster for later use. 2. Using the geometric center of the cladding as a reference point, determine the corresponding dimensional boundary of the substrate requiring non-ferrous metal lamination, which is 2960mm. 2840mm, grind out a slope outside the dimension boundary (the angle with the pre-bonding surface is 171.5°), leave a 2mm blunt edge at the bottom of the slope, the slope surface is relatively regular and uniform; then turn the cover plate over, and use the same method to determine the size of the substrate to be composited with non-ferrous metals, and use a grinding wheel to cut a stress groove around the dimension line (the center line of the stress groove on the pre-bonding surface coincides with the top of the slope), the groove depth is 3mm, the groove width is 2mm, and the cover plate for use in the locally composite explosive welded composite plate is prepared for later use. 3. Place the prepared substrate horizontally on a suitable bonding bed free of hard foreign objects. After cleaning the area to be bonded, place the substrate according to the process requirements, with a spacing of 10mm. Then, place the cover plate horizontally, aligning the geometric center of the area on the substrate where the non-ferrous metal needs to be bonded (see the partial bonding diagram). Figure 4 As shown, Figure 4 The shaded area is the local composite area, and the dot is the detonation point); the top of the slope of the cladding plate joint surface and the stress groove on the back side are exactly corresponding to the boundary of the substrate; then, an L-shaped explosive frame is set around the upper surface of the cladding plate, so that the bottom edge of the L-shaped explosive frame extends 10mm beyond the edge of the cladding plate, and the vertical edge of the explosive frame is fixed perpendicularly to the cladding plate. 4. Evenly spread the prepared explosive welding-specific explosive onto the cover plate, level it with a special tool, and adjust the charge height to the designed charge height of 40±2mm. Then, manually reduce the explosive height from the stress groove to the edge of the explosive frame (slope position) by 10% to 36mm. Subsequently, set the detonation point near the edge at the middle of the longer side of the outer free face of the explosive placement area, i.e., the side with a length of 3000mm, and vertically insert the digital electronic detonator and connect the detonator lead wire. 5. Detonating the detonator and explosives yields a locally composite S32168 explosively welded composite plate. Ultrasonic non-destructive testing is performed according to NB / T47013.3-2023. The detonation point area has… The detonator area is 25mm wide, with 100% bonding in other areas. After heat treatment, leveling, cutting, and polishing, a partially composite S32168+Q345R tube sheet is obtained, with dimensions of (5mm + 56mm). 2920mm 3800mm, the size of the non-ferrous metal composite area is 2920mm. The detonator area is 2800mm long, and the edge portion is outside the effective dimensions; it was removed during edge cutting. Testing shows it meets the requirements of NB / T 47002.1-2019 B1 grade, with a shear strength of 308 MPa, exceeding the ≥210 MPa requirement in the composite standard. Ultrasonic non-destructive testing was performed at the boundary between the composite area and the exposed carbon steel area, and no internal defects were found in the carbon steel.

[0036] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0037] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a partially composite explosively welded composite plate, characterized in that, Includes the following steps: 1) A bevel and blunt edge are formed at the edge of the pre-bonding surface of the cover plate, and a stress groove is set on the back of the pre-bonding surface of the cover plate to obtain a cover plate for explosive welding composite plate with local composite structure. 2) The partially composite exploded welded composite plate is explosively welded to the substrate using a cover plate to obtain a partially composite exploded welded composite plate; The explosive loading method for the explosive welding is an extended charge.

2. The method for preparing a partially composite explosively welded composite plate according to claim 1, characterized in that, In step 1), the angle between the slope and the pre-bonded surface is 155~172°, and the size of the blunt edge is ≤1 / 2 of the thickness of the cover plate and not greater than 4mm.

3. The method for preparing a partially composite explosively welded composite plate according to claim 2, characterized in that, The orthographic projection of the centerline of the stress groove onto the pre-bonded surface coincides with the top of the slope. The width of the stress groove is 2~5mm, and the depth is ≥1 / 2 of the thickness of the cover plate.

4. A method for preparing a partially composite explosively welded composite plate according to any one of claims 1 to 3, characterized in that, In step 2), the explosive welding process involves a partially composite explosive welding composite plate with a cover plate arranged parallel to the substrate. The orthogonal projection of the partially composite explosive welding composite plate with a cover plate onto the substrate is the partially composite area.

5. The method for preparing a partially composite explosively welded composite plate according to claim 4, characterized in that, The extended charge is an explosive whose projected area in the direction of the cover plate of the locally composite explosive welded composite plate is greater than the area of ​​the cover plate of the locally composite explosive welded composite plate. The extension length of the extended charge is 10~15mm.

6. The method for preparing a partially composite explosively welded composite plate according to claim 5, characterized in that, The explosive loading in the explosive welding includes a central explosive loading area and an edge explosive loading area; In the case of locally composite explosively welded composite plates, the area corresponding to the orthographic projection of the non-slope position of the cladding plate is the central explosive loading area; the area corresponding to the orthographic projection of the slope position is the edge explosive loading area. The explosive loading height in the central explosive loading area is 30~95mm; The explosive loading height in the edge explosive loading area gradually decreases from the center to the periphery, with the minimum explosive loading height in the edge explosive loading area decreasing to 88-92% of that in the central explosive loading area.

7. The method for preparing a partially composite explosively welded composite plate according to claim 6, characterized in that, When the composite area of ​​the locally composite explosively welded composite plate is located at the edge of the substrate, the detonation point is set at the edge. When the composite area of ​​the partially composite explosively welded composite plate is located at the center of the substrate, the detonation point is set as the geometric center of the cover plate of the partially composite explosively welded composite plate.

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