Method for reducing deformation of composite tube plate in explosive welding process

Abstract

The invention belongs to the technical field of explosive welding of composite tube plates, and provides a method for reducing deformation of a composite tube plate in the explosive welding process. The method comprises the following steps: pre-leveling a base plate, pre-treating the base plate and a compound plate before explosion, manufacturing an explosion bed, mounting the base plate and the compound plate in parallel, arranging a'trapezoidal 'explosive, placing a detonator, and detonating the detonator, so as to obtain the explosion composite tube plate. And carrying out stress relief heat treatment on the explosive cladding tube plate. A trapezoidal explosive distribution structure is adopted, on the premise that the inclined collision speed of the base plate and the composite plate is within a weldable window, the situation that the explosion thinning amount is out of tolerance due to the fact that the edge collision kinetic energy is too large due to superposition of detonation energy is effectively avoided, and the uniformity of the overall composite layer thickness of the composite tube plate is effectively guaranteed; according to the composite tube plate produced through the method, the problems that in the machining and assembling process, due to the fact that flatness is out of tolerance, a drilling tool is stuck in the drilling process, machining and assembling difficulty is large, and a sealing face leaks can be solved.

Description

Technical Field

[0001] The invention relates to the technical field of explosively welded composite tube sheets, and in particular to a method for reducing deformation during explosive welding of composite tube sheets. Background Art

[0002] Explosive welding is a special welding method that uses explosives to drive metal plates to collide at high speed and form metallurgical bonding between metals. The basic principle of explosive welding is that when the explosives are detonated on the metal plate to be welded (usually called the composite plate), the explosives react rapidly to release a large amount of energy, generating a strong shock wave, which acts on the composite plate at extremely high speed and pressure, causing it to move at high speed toward another metal plate (substrate). At the moment when the composite plate and the substrate collide at high speed, the metal material on the contact surface will undergo severe plastic deformation. At the same time, due to the high temperature and high pressure generated by the collision, the atoms on the surfaces of the two metals diffuse with each other, forming a special metallurgical bonding interface, thereby realizing the welding of the two metals. Explosive welding has two major advantages. One is that it is suitable for large-area composite of metal materials; the other is that it can control the reaction between metals and weld dissimilar metals that cannot be welded by conventional welding methods. Composite tube sheets are widely used in many fields and industries such as petrochemicals, heat exchangers, condensers, and chemical reactors due to their good performance and high cost performance. However, due to technical reasons and policy restrictions, traditional composite tube sheets are mostly completed using cladding technology. The long processing cycle, many factors affecting the cladding process and high production costs have greatly restricted industrial development and upgrading.

[0003] With the advancement of explosive welding technology and the successful application of explosive welded composite tube sheets, explosive welded composite tube sheets have received more and more attention and recognition from the industry. However, how to control the deformation during the explosive welding process and the flatness of the finished product has become a new problem plaguing the industry. Summary of the invention

[0004] The purpose of the present invention is to provide a method for reducing the deformation of composite tube sheet during explosion welding in view of the shortcomings of the prior art. The present invention controls and reduces the deformation of explosion welding by detailed control and process adjustment during explosion welding, so as to meet the high standard requirements of the flatness of the whole plate in the subsequent machining and assembly process of the composite tube sheet.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for reducing deformation during composite tube sheet explosion welding, comprising the following steps:

[0007] 1) Substrate pre-leveling: Pre-level the substrate to make the flatness of the substrate reach 1-2mm of the whole board;

[0008] 2) Pretreatment of the base plate and the clad plate before explosion: Polish the bonding surfaces of the base plate and the clad plate, and stack the polished bonding surface of the base plate and the polished bonding surface of the clad plate relatively;

[0009] 3) Explosion bed production: Lay a backing plate on the explosion foundation, and lay a fine sand buffer layer above the backing plate;

[0010] 4) Parallel installation of the base plate and the clad plate: Place the polished base plate on the fine sand buffer layer, place V-shaped feet on the polished base plate, and install the polished clad plate parallel above the polished base plate;

[0011] 5) "Trapezoidal" explosive placement: Lay special explosive for explosion cladding on the surface of the polished clad plate. The special explosive for explosion cladding is placed in a "trapezoidal" structure, and the difference in the height of the explosive in the area with a central diameter of 1 m and the height of the explosive at the edge is 8-10 mm;

[0012] 6) Placement of detonator: Dig a "reverse cone" shaped charge hole at the center of the explosive area, put pure explosive, insert the detonator vertically into the center of the pure explosive, and the bottom shaped charge cavity of the detonator contacts the clad plate surface;

[0013] 7) Detonate the detonator to obtain an explosion-clad tube sheet;

[0014] 8) Conduct stress relief heat treatment on the explosion-clad tube sheet.

[0015] Preferably, the surface finish of the polished bonding surface of the base plate in step 2) ≤ 2.0 μm; the surface finish of the polished bonding surface of the clad plate ≤ 1.6 μm; the polishing treatment uses abrasive belts and flap wheels.

[0016] Preferably, the size of the backing plate in step 3) is slightly larger than the size of the base plate, the thickness of the backing plate is 8-16 mm, and the thickness of the fine sand buffer layer is 30-40 mm.

[0017] Preferably, in step 4), the polished clad plate and the polished base plate are concentric, and the V-shaped opening direction of the V-shaped feet is consistent with the detonation direction.

[0018] Preferably, the height of the explosive in the area with a central diameter of 1 m in step 5) is 53-62 mm, and the height of the explosive at the edge is 43-54 mm; the detonation velocity of the special explosive for explosion cladding is 1900-2100 m / s, and the density is 0.75-0.9 g / m 3 , and the brisance is 9-9.5 mm.

[0019] Preferably, the height of the pure explosive in step 6) is equal to the height of the explosive in the area with a central diameter of 1 m; the detonation velocity of the pure explosive is 3400-3600 m / s, and the brisance is 13-15 mm;

[0020] Step 5) also includes presetting detonators. When presetting the detonators, in step 6), pure explosives are placed into the detonators.

[0021] Preferably, in step 7), the explosion - clad tube sheet is slightly deformed. The whole plate is subjected to UT non - destructive testing, the bonding rate is ≥99.9%, and the unbonded area at the detonation point is ≤φ2.5mm.

[0022] The beneficial effects of the present invention include the following aspects:

[0023] 1) The present invention controls the flatness from the source of the production process. On the basis of ensuring that the local deformation stress is not large, the substrate is adjusted to the optimal flatness state, which not only ensures the bonding quality of the composite tube sheet, but also effectively reduces the abnormal local deformation caused by the uneven distribution of local stress during the explosion welding process.

[0024] 2) The explosion bed of the present invention combines a backing plate and a fine sand buffer layer, which can effectively reduce the adverse effects of explosion shock on the substrate and the bonding surface while controlling and reducing explosion deformation.

[0025] 3) The backing plate of the present invention is realized by splicing carbon steel scraps. According to the requirements of the product plate width and thickness, the scraps can be arbitrarily selected for splicing, and after leveling, it can be reused repeatedly with extremely low cost, fully meeting the needs of increasing efficiency and reducing consumption.

[0026] 4) The present invention adopts a "trapezoidal" charge structure. On the premise that the inclined collision speed of the base plate and the clad plate meets the weldable window, it effectively avoids the excessive explosion thinning caused by the excessive edge collision kinetic energy due to the superposition of detonation energy, and effectively ensures the uniformity of the overall clad layer thickness of the composite tube sheet.

[0027] 5) The composite tube sheet produced by the method of the present invention can solve problems such as "drill jamming" during the drilling process, difficult machining and assembly, and leakage of the sealing surface caused by excessive flatness deviation during the machining and assembly processes. Detailed implementation mode

[0028] The present invention provides a method for reducing the deformation amount during the explosion welding of a composite tube sheet, which includes the following steps:

[0029] 1) Substrate pre - leveling: The substrate is pre - leveled so that the flatness of the substrate reaches 1 - 2mm for the whole plate;

[0030] 2) Pre - treatment of the substrate and the clad plate before explosion: The bonding surface of the substrate and the bonding surface of the clad plate are polished, and the polished bonding surface of the substrate and the polished bonding surface of the clad plate are stacked relative to each other;

[0031] 3) Explosion bed production: A backing plate is laid on the explosion foundation, and a fine sand buffer layer is laid above the backing plate;

[0032] 4) Parallel installation of the substrate and the clad plate: Place the polished substrate on the fine sand buffer layer, place V-shaped feet on the polished substrate, and install the polished clad plate parallel above the polished substrate;

[0033] 5) "Trapezoidal" explosive placement: Lay the special explosive for explosive cladding on the surface of the polished clad plate. The special explosive for explosive cladding is placed in a "trapezoidal" structure, and the difference in the height of the explosive in the central area with a diameter of 1 meter and the height of the explosive at the edge is 8 - 10 mm;

[0034] 6) Place the detonator: Drill a "reverse cone" - shaped blasting hole at the center of the explosive area, put pure explosive into it, insert the detonator vertically into the center of the pure explosive, and the shaped charge cavity at the lower end of the detonator contacts the surface of the clad plate;

[0035] 7) Detonate the detonator to obtain the explosively clad tube sheet;

[0036] 8) Conduct stress relief heat treatment on the explosively clad tube sheet.

[0037] In step 1) of the present invention, during the pre - leveling treatment of the substrate, pay attention to protecting the surface of the substrate; since the substrate has not undergone explosive processing and the deformation stress of local ductile deformation is small, through pre - leveling treatment, its flatness can be corrected to the optimal state very well. At the same time, good substrate flatness greatly improves and promotes both the forming quality and the bonding strength of explosive welding.

[0038] In the present invention, for the bonding surface of the polished substrate in step 2), the surface finish is preferably ≤2.0 μm, more preferably ≤1.8 μm, and still more preferably ≤1.5 μm; for the bonding surface of the polished clad plate, the surface finish is preferably ≤1.6 μm, more preferably ≤1.5 μm, and still more preferably ≤1.3 μm; the polishing treatment preferably uses abrasive belts and flap wheels.

[0039] In the present invention, the purpose of the polishing treatment in step 2) is to remove the oxide film and surface rust on the bonding surface of the substrate and the clad plate, so that the bonding surface shows metallic luster and has no surface defects such as impurities, pits, oil stains, and pockmarks that affect the bonding quality; according to the different plate widths and different materials of the substrate and the clad plate, select appropriate types and specifications of abrasives.

[0040] In the present invention, for the size of the backing plate in step 3), it is preferably slightly larger than the size of the substrate. The thickness of the backing plate is preferably 8 - 16 mm, more preferably 9 - 15 mm, and still more preferably 10 - 13 mm. The thickness of the fine sand buffer layer is preferably 30 - 40 mm, more preferably 32 - 38 mm, and still more preferably 34 - 35 mm.

[0041] In the present invention, there are no obvious stones and other hard objects in the fine sand soil described in step 3). A backing plate is laid on the explosive foundation. The function of laying fine sand soil above the backing plate is as follows: If we want to control the deformation during explosive welding, there are various uncertain factors relying solely on the conventional sand bed. Parameters such as the stacking density, water content, particle size, and looseness of the sand have varying degrees of differences. Under the huge explosive load, the deformation depressions presented are also different. Therefore, a backing plate is laid on the explosion bed, and at the same time, a certain thickness of fine sand soil is evenly laid above the backing plate. On the basis of ensuring uniform bearing of the explosive deformation, it can also effectively reduce the explosive impact between the substrate and the backing plate, and avoid damage to the bonding quality and the substrate caused by the "rigid foundation".

[0042] In step 4) of the present invention, the polished clad plate and the polished substrate are kept concentric, and the V-shaped opening direction of the V-shaped feet is preferably the same as the detonation direction.

[0043] In step 4) of the present invention, ensure that the boundary of the substrate is within the boundary range of the backing plate, the bonding surface of the clad plate faces downward, the bonding surface of the substrate faces upward, the bonding surfaces of the substrate and the clad plate are opposite to each other, a distance equal to the height of the V-shaped feet is reserved between the substrate and the clad plate, and the V-shaped feet do not collapse or deform.

[0044] In step 4) of the present invention, the number and requirements of the V-shaped feet placement vary with the changes in the plate width and thickness.

[0045] In the present invention, in step 5), the height of the explosive in the area with a central diameter of 1 m is preferably 53 - 62 mm, more preferably 55 - 60 mm, and even more preferably 56 - 58 mm; the height of the explosive at the edge is preferably 43 - 54 mm, more preferably 45 - 52 mm, and even more preferably 47 - 50 mm; the detonation velocity of the special explosive for explosive cladding is preferably 1900 - 2100 m / s, more preferably 1920 - 2050 m / s, and even more preferably 1950 - 2000 m / s, and the density is preferably 0.75 - 0.9 g / m 3 , more preferably 0.76 - 0.87 g / m 3 , even more preferably 0.8 - 0.85 g / m 3 , and the brisance is preferably 9 - 9.5 mm, more preferably 9.1 - 9.4 mm, and even more preferably 9.2 - 9.3 mm.

[0046] In the present invention, it is preferred to use a titanium scraping tool to lay the explosive evenly, and then use a wooden explosive collecting plate to collect the explosive from the edge to the middle, and the explosive is arranged in a "trapezoidal" shape as a whole.

[0047] In step 5) of the present invention, although uniform drug distribution can theoretically achieve stable detonation transmission, in the actual production process, with the extension of the detonation time, both the detonation energy and the wave front of the detonation wave show an increasing trend. The superposition of energy will also increase the explosion thinning amount and the uniformity of explosive deformation. Therefore, a "trapezoidal" drug distribution structure is adopted to make the detonation process relatively stable and uniform to a certain extent, so as to control and reduce the explosion deformation and the excessive local explosion thinning amount.

[0048] In the present invention, the height of the pure explosive in step 6) is preferably the same as the height of the explosive in the area with a central diameter of 1 m; the detonation velocity of the pure explosive is preferably 3400 - 3600 m / s, more preferably 3450 - 3550 m / s, and even more preferably 3500 m / s; the brisance is preferably 13 - 15 mm, more preferably 13.5 - 14.5 mm, and even more preferably 14 mm.

[0049] Step 5) also includes pre-setting a detonator. When pre-setting the detonator, pure explosive is placed in the detonator in step 6).

[0050] In the present invention, in step 7), the explosion-clad tube sheet is slightly deformed. The whole plate is subjected to UT non-destructive testing. The bonding rate is preferably ≥99.9%, more preferably ≥99.95%, and even more preferably ≥99.99%. The unbonded area at the detonation point is preferably ≤φ2.5 mm, more preferably ≤φ2.0 mm, and even more preferably ≤φ1.5 mm.

[0051] In the present invention, in step 7), the unbonded area at the detonation point is welded and repaired according to the relevant regulations and requirements in NB / T 47002 and NB / T 47015, or it can be not repaired when meeting the requirements that partial non-fitting areas are allowed to exist in the standard.

[0052] After the on-site operators evacuate to the safe area, detonate the detonator according to the operation requirements of the blasting regulations.

[0053] In the present invention, in step 8), the explosion-clad tube sheet is successively subjected to stress relief heat treatment, leveling, cutting, and finishing to obtain an explosion-clad tube sheet with a flatness of 1.5 - 3 mm for the whole plate and a bonding rate of 100%.

[0054] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0055] Example 1

[0056] The base plate is a Q345R steel plate, 36 * φ3450 mm, and the clad plate is an S22053 stainless steel plate, 8 * φ3490 mm. The base plate is pre-leveled by a high-precision intelligent seven-roll leveling machine, and the flatness of the base plate is adjusted to 1.5 - 2 mm for the whole plate.

[0057] The bonding surface of the substrate is polished with a 60-mesh abrasive belt to remove the oxide film and surface rust, and then the bonding surface is polished with an 80-mesh flap wheel to meet the requirement of a surface finish of 2.0 μm; the bonding surface of the cladding plate is polished with an 80-mesh flap wheel to remove the surface oxide film and expose the metallic luster, so that the surface finish of the bonding surface meets the requirement of 1.6 μm. Then, the bonding surfaces of the polished substrate and the polished cladding plate are stacked relative to each other and waiting for detonation.

[0058] On the initially leveled explosion foundation with guaranteed levelness, lay 1 piece of φ3600 backing plate (carbon steel material) with a thickness of 10 mm horizontally, and lay a layer of fine sand buffer layer with a thickness of 30 - 35 mm above the backing plate, ensuring uniform laying and 40 - 45 mm higher than the surrounding area, and then make marks at the boundary position of the backing plate.

[0059] Place the polished substrate (bonding surface facing up) horizontally on the fine sand buffer layer, ensuring that the boundary of the substrate is completely within the marks of the backing plate boundary. Clean the bonding surface of the polished substrate to remove floating dust and debris, and clean the bonding surface with the cleaning agent acetone. Then, place V-shaped feet evenly in a ring around the polished substrate (within the boundary), with the height of the V-shaped feet being 10 mm, the V-shaped opening facing outward and consistent with the detonation direction, and the distance between adjacent V-shaped feet being 400 - 450 mm. Subsequently, install the cleaned polished cladding plate with the bonding surface facing down parallel to the substrate, ensuring that the cladding plate is concentric with the substrate after installation and the V-shaped feet do not collapse or deform.

[0060] Arrange a ring-shaped medicine frame around the cladding plate, and then evenly lay the specially configured explosive for explosive cladding with a detonation velocity of 2050 m / s and a density of 0.87 g / cm 3 ³ and a brisance of 9.2 mm in the medicine frame. Use a titanium scraping tool to lay the explosive evenly, and then use a wooden medicine collecting plate to collect the medicine from the edge to the middle, ensuring that the height of the explosive within a 1-meter diameter range in the center is 60 mm, and the height of the explosive starts to decrease towards the edge from 745 mm away from the edge, showing a "trapezoidal" layout as a whole, with the height of the explosive at the edge being 52 mm.

[0061] After the explosive laying is completed, dig out an "inverted cone"-shaped medicine hole at the center position of the specially configured explosive for explosive cladding, put 50 g of pure explosive into it, the detonation velocity of the pure explosive is 3500 m / s and the brisance is 14 mm, the height of the pure explosive is flush with the height of the explosive in the 1-meter diameter area in the center, and then vertically insert the digital electronic detonator into the center of the pure explosive, with the bottom-shaped cavity of the detonator in contact with the cladding plate surface.

[0062] After the leg wires of the detonator are connected and pass the inspection, detonate it to obtain 1 piece of duplex steel / steel composite tube sheet with a material combination of S22053 + Q345R and a size specification of (8 + 36) * φ3450. The whole shows slight deformation and no local deep deformation.

[0063] After 100% UT inspection, except for the non-bonding at the position of φ2.5mm at the initiation point, all other positions are 100% bonded; after the non-bonding area at the initiation point is welded and repaired according to the corresponding regulations in NB / T 47015 and NB / T 47002, stress relief heat treatment is carried out in a resistance furnace. The heat treatment temperature is 530°C, the holding time is 130min, and the heating and cooling rate ≤ 120°C / h. After being taken out of the furnace, it is leveled by a high-precision intelligent seven-roll leveling machine, and then cut, polished and packaged.

[0064] The final size of the composite tube sheet in this embodiment is: (8 + 36)*φ3420, and the flatness is 2mm for the whole plate, which is applied to the tube sheet of the heat exchanger in a well-known domestic petroleum refining process equipment.

[0065] Example 2

[0066] The base plate is a SA516Gr70 42*φ2980mm steel plate, and the clad plate is an ASME SB265 Gr2 titanium plate, 6*φ3030mm. The clad plate is butt-welded by argon arc welding method, and the reinforcement on the upper and lower surfaces of the weld is ground flat. After 100% PT penetration inspection to ensure compliance, the clad plate is then leveled by a thirteen-roll leveling machine; after the base plate is cut and blanked, the cutting slag around is cleaned up, and the base plate is pre-leveled by a high-precision intelligent seven-roll leveling machine, and the flatness of the base plate is adjusted to 1.0 - 1.5mm for the whole plate.

[0067] The bonding surface of the base plate is polished with a 60-mesh sand belt to remove the oxide film and surface rust, and then the bonding surface is polished with an 80-mesh flap wheel to make the surface finish of the bonding surface meet the requirement of 2.0μm; the bonding surface of the clad plate is polished with an 80-mesh flap wheel to remove the surface oxide film and expose the metallic luster, and make the surface finish of the bonding surface meet the requirement of 1.6μm. A 2mm-thick EPE pearl cotton is laid on the bonding surface of the base plate, and then the bonding surfaces of the polished base plate and the polished clad plate are stacked face to face and waiting for explosion.

[0068] On the explosion foundation with preliminary leveling and ensuring the levelness, a φ3000 backing plate (carbon steel material) with a thickness of 8mm is horizontally laid, and a fine sand buffer layer with a thickness of 32 - 35mm is laid above the backing plate to ensure uniform laying and 40 - 42mm higher than the surrounding area, and then marks are made at the boundary position of the backing plate.

[0069] Place the polished substrate horizontally on the fine sand buffer layer (with the bonding surface facing up) to ensure that the boundary of the substrate is completely within the mark of the pad boundary. Clean the bonding surface of the polished substrate to remove dust and debris, and clean the bonding surface with acetone, a cleaning agent. Then place titanium V-shaped pads around the polished substrate (within the boundary). The height of the V-shaped pads is 8mm, and the V-shaped opening direction faces outward, consistent with the direction of explosion transmission. Five V-shaped pads are evenly placed in the middle position between the boundary and the center of the circle of the substrate. Then install the cleaned polished composite plate with the bonding surface facing down and parallel to the substrate, ensuring that the composite plate remains concentric with the substrate after installation, and the V-shaped pads do not collapse or deform.

[0070] Arrange a circular charge frame around the double plate, apply a 1.3mm thick protective layer evenly on the double plate surface with industrial butter, preset a φ20mm detonator at the center of the circle, and then evenly lay the configured explosives with a detonation speed of 1920m / s and a density of 0.76g / cm in the charge frame. 3 , special explosives for titanium-steel composite plates with a strength of 8.3mm. Use a titanium scraper tool to spread the explosives evenly, and then use a wooden collecting plate to collect the explosives from the edge to the middle, ensuring that the height of the explosives within the center diameter of 1 meter is 56mm. Starting from 500mm from the edge, the height of the explosives decreases toward the edge, forming a "trapezoidal" arrangement as a whole, and the height of the explosives at the edge is 48mm.

[0071] After the charge is laid, 48g of pure explosive is placed in the detonator at the center of the explosive. The detonation velocity of the pure explosive is 3500m / s, the intensity is 14mm, and the height of the pure explosive is level with the height of the explosive in the 1-meter diameter area in the center. Then, the digital electronic detonator is vertically inserted into the center of the pure explosive, and the energy-gathering hole at the lower end of the detonator is in contact with the composite plate surface.

[0072] The detonator leg wires were connected and detonated after passing the test, resulting in a titanium steel composite tube sheet with a material combination of ASME SB265 Gr2+SA516Gr70 and a size specification of (6+42)*φ2980. The overall deformation was slight and there was no local deep deformation.

[0073] Due to the particularity of titanium steel composite plate, UT non-destructive testing was performed using engine oil as a coupling agent. After 100% UT testing, except for the 2.0mm non-bonding area at the detonation point, all other positions were 100% bonded. The 20.0mm non-bonding area at the detonation point can meet the Class B requirements of ASTM B898. No welding repair is performed, and stress relief heat treatment is directly performed in a resistance furnace. The heat treatment temperature is 540℃, the holding time is 145min, and the heating and cooling speed is ≤110℃ / h. After leaving the furnace, a high-precision intelligent seven-roller leveling machine is used for leveling, followed by cutting, polishing, and packaging.

[0074] The final dimensions of the composite tube sheet in this embodiment are: (6 + 42) * φ2930, and the flatness is 2 mm for the whole sheet. This composite tube sheet is applied to the tube sheet of a heat exchanger in a certain export PTA project, and the required delivery dimensions are (6 + 42) * φ2930 mm, meeting ASTM B898 Class B.

[0075] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for reducing deformation during explosion welding of composite tube sheets, characterized in that: The following steps are included: 1) Substrate pre-leveling: Pre-level the substrate to make the flatness of the substrate reach 1-2mm of the whole board; 2) Pretreatment of the substrate and the composite plate before blasting: polishing the bonding surface of the substrate and the bonding surface of the composite plate, and stacking the polished bonding surface of the substrate and the polished bonding surface of the composite plate relative to each other; 3) Explosive bed production: lay a pad on the blast foundation, and lay a fine sand buffer layer on top of the pad; 4) Install the base plate and the backing plate in parallel: Place the polished base plate on the fine sand buffer layer, place V-shaped pads on the polished base plate, and install the polished backing plate parallel to the polished base plate; 5) "Trapezoidal" explosive distribution: Lay the special explosives for explosive composite on the surface of the polished composite plate. The special explosives for explosive composite are laid in a "trapezoidal" structure. The difference between the height of the explosives in the area with a central diameter of 1 meter and the height of the explosives at the edge is 8 to 10 mm; 6) Place the detonator: dig out an "inverted cone" shaped charge hole at the center of the explosive surface, put in pure explosive, and vertically insert the detonator into the center of the pure explosive, with the energy-gathering hole at the lower end of the detonator in contact with the composite plate surface; 7) detonating the detonator to obtain an explosive composite tube sheet; 8) Perform stress relief heat treatment on the explosive composite tube sheet.

2. The method according to claim 1, characterized in that Step 2) The smoothness of the bonding surface of the polished substrate is ≤2.0 μm; the smoothness of the bonding surface of the polished composite plate is ≤1.6 μm; the polishing process uses an abrasive belt and a flap wheel.

3. The method according to claim 1 or 2, characterized in that: Step 3) The size of the pad is slightly larger than that of the base plate, the thickness of the pad is 8 to 16 mm, and the thickness of the fine sand buffer layer is 30 to 40 mm.

4. The method according to claim 3, characterized in that In step 4), the polished composite plate and the polished base plate are kept concentric, and the V-shaped opening direction of the V-shaped foot is consistent with the explosion transmission direction.

5. The method according to claim 3, characterized in that: Step 5) The height of the explosive in the central diameter area of ​​1 meter is 53-62 mm, and the height of the explosive in the edge is 43-54 mm; the detonation velocity of the special explosive for explosive composite is 1900-2100 m / s, and the density is 0.75-0.9 g / m 3 , the intensity is 9 to 9.5 mm.

6. The method according to claim 4 or 5, characterized in that: Step 6) The height of the pure explosive is equal to the height of the explosive in the area with a central diameter of 1 meter; the detonation velocity of the pure explosive is 3400-3600 m / s, and the intensity is 13-15 mm; Step 5) further includes presetting the detonator. When the detonator is pre-set, step 6) is to put pure explosives into the detonator.

7. The method according to claim 6, characterized in that Step 7) The explosive composite tube sheet is slightly deformed, and the whole plate is subjected to UT non-destructive testing, with a bonding rate of ≥99.9% and an unbonded area at the detonation point of ≤φ2.5mm.