Machining method for radiator of cantilever structure

Abstract

The invention discloses a method for processing a radiator with a cantilever structure, which comprises the following steps of: reserving allowance on the end surface of a mounting seat, splitting a bypass plate into an upper plate and a lower plate, welding the lower bypass plate and a bracket, fully releasing welding deformation, correcting deformation of a metal plate, and milling to remove the allowance on the end surface to ensure that the planeness is not greater than the requirement of a part drawing. Deformation is reserved for welding and plugging the upper bypass plate finally, and then a mounting hole is milled to serve as the reference of follow-up welding. And then, by taking the mounting seat and the mounting hole as references, assembling on a welding fixture to position the hot-side end cover and the cold-side end cover for welding, and finally, welding the upper bypass plate to form a complete radiator. By means of the machining method, the problems that when a traditional method is used for machining the radiator of the cantilever structure, the qualification rate is low, and repairing and reworking are difficult are solved, and the problem that deformation of the cantilever structure is out of tolerance in the welding process can be effectively solved.

Description

Technical Field

[0001] The present invention relates to a processing method for a cantilever structure radiator in the field of welding processing, and belongs to the technical field of radiator processing. Background Art

[0002] Chinese invention patent CN217198666U (publication date: August 16, 2022) discloses a special-shaped air / liquid heat exchanger for an aircraft environmental control system. This heat exchanger product belongs to the radiator products on aircraft. Due to the urgent need for research and development, the main factory has an urgent demand for the product and needs to deliver it urgently. As Figure 2 , there are two independent cavities on the air side (cold side outlet end cover). The right cavity corresponds to the heat dissipation core, and the left side is a cavity suspended beside the core assembly. The partition between the two is a weld seam. As Figure 3 , the design requires the tolerance of the installation interface size of the product to be within the range of ±0.2 mm and ±0.5 mm, and the flatness requirement of the mounting seat is 0.5 mm.

[0003] The traditional processing method is as follows: According to the product design structure, with the mounting seat as the reference, first weld the cold side, hot side end covers and each inlet and outlet nozzle, weld the weld seam between the partition plate inside the cold side outlet end cover (required to be welded and separated between the core assembly and the bypass side to form two cavities) and the core assembly to form Figure 2 the first cavity on the right side in , then weld the bypass plate to block the left side to form the second cavity, and finally weld the bracket to complete the processing of the overall structure of the product.

[0004] However, the qualified rate of the traditional processing method is low. This is because the product is made of aluminum alloy material with a large linear expansion coefficient, and it is easy to deform during welding. Moreover, the product has a cantilever structure, and the deformation amount on the cantilever side after welding is about 5 mm. The mounting seat is used as the processing reference, and the bypass plate and the cantilever side are in a vertical position relationship. After welding, the transverse contraction of the weld seam causes the two mounting seats on the cantilever side to warp upward (the flatness of the mounting seat is 2 - 3 mm, and the installation hole position tolerance exceeds 2 - 5 mm). Even if the flatness is corrected after welding, the hole position size cannot be guaranteed. Finally, when welding the bracket, the two mounting seats on the cantilever side warp again. At this time, the product structure has been stabilized, and the sheet metal cannot be corrected back to the deformation.

[0005] On the other hand, it is difficult to repair the product with out-of-tolerance. The reference of the product is affected by welding deformation, and the size is out of tolerance. It is difficult to find the reference size during repair. Moreover, the product structure has been formed, and it is necessary to disassemble the bracket and open the bypass plate to slowly correct the sheet metal to find the reference. However, after re-welding, there is still a risk of deformation and out-of-tolerance. Summary of the Invention

[0006] The present invention aims to provide a processing method for a radiator with a cantilever structure, which can still ensure that the product installation interface dimensions are within the tolerances of ±0.2 mm and ±0.5 mm even in the case of severe welding deformation, meet the design requirements, and achieve the installation requirements.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A processing method for a radiator with a cantilever structure, the radiator with a cantilever structure mainly consists of a cold-side inlet end cover, a cold-side outlet end cover, a hot-side outlet end cover, a mounting seat, a core assembly, a bracket and a bypass plate. There is a planar cantilever edge extending towards the outside of the core assembly on the bottom plane of the core assembly. The processing method includes:

[0009] Step 1: Weld all the mounting seats on the end face of the non-core-assembly side of the cantilever edge, and leave a machining allowance on the end face of the end of the mounting seat far from the cantilever edge.

[0010] Step 2: Split the bypass plate into two pieces. One piece far from the cantilever edge is used as the upper bypass plate, and one piece close to the cantilever edge is used as the lower bypass plate. First, weld the two side edges of the lower bypass plate to the end face of the corresponding core-assembly side of the cantilever edge and the core assembly respectively, and weld the bracket on the end face of the corresponding core-assembly side of the cantilever edge.

[0011] Step 3: Perform stress relief treatment on the welded parts completed in Step 2.

[0012] Step 4: Perform sheet metal correction on the parts completed in Step 3 for stress relief treatment to correct the deformation of the cantilever edge and the mounting seat.

[0013] Step 5: Perform margin cutting on the end face of the end of the mounting seat far from the cantilever edge of the parts completed in Step 4 for sheet metal correction, ensure that the flatness of the end face of the end of all mounting seats far from the cantilever edge is less than the flatness requirement of the end face of the mounting seat in the design drawing, and machine mounting holes on the end face of the end of the mounting seat.

[0014] Step 6: Take the end face and mounting holes of the mounting seat completed in Step 5 for milling as the assembly and welding reference, and assemble and weld the cold-side inlet end cover, the cold-side outlet end cover, and the hot-side outlet end cover to the cold-side inlet side, the cold-side outlet side, and the hot-side outlet side of the core assembly respectively. When welding the cold-side outlet end cover to the cold-side outlet side of the core assembly, it also includes welding to the lower bypass plate.

[0015] Step 7: Weld the upper bypass plate to the lower bypass plate, the cold-side outlet end cover, and the core assembly.

[0016] As an option, in Step 3, annealing is used to remove the welding stress.

[0017] As an option, in the fifth step, milling is used to remove the surplus on the end face of the mounting base away from the cantilever edge.

[0018] As an option, in the fifth step, milling is used to machine mounting holes on the end face of the mounting base.

[0019] Compared with the prior art, in the welding method of the present invention, the cantilever edge is welded to the bracket and the mounting base under an open structure (here, the open structure means that the lower bypass plate, the bracket, and the two mounting bases are not restricted or implicated by other structures (such as the core assembly or the end cover), and the end of the cantilever edge is in a free state, and the welding deformation can be completely released), reducing the welding constraint. After welding, stress relief annealing is carried out, and then sheet metal correction is carried out to ensure the design dimensions.

[0020] Compared with the prior art, the present invention provides a processing method for a radiator with a cantilever structure, which solves the problem that the position dimensions of the hot-side inlet end cover, the outlet end cover, the cold-side inlet end cover, and the outlet end cover exceed the tolerance due to the deviation of the mounting base used as a reference in the traditional processing method during the deformation of the radiator. After adopting the processing method of the present invention, the welding sequence and the welding method of the components are substantially adjusted, so that the reference surface on the mounting base meets the requirements and is no longer affected by the welding deformation, ensuring that the geometric tolerances of the subsequent cold-side end cover, the hot-side end cover, and other components meet the requirements of the drawing design. Finally, the problem of rework and repair caused by the dimensional tolerance of the radiator is avoided, the product qualification rate is improved, the cost of rework and repair is reduced, the production efficiency is improved, and the processing cycle is shortened.

[0021] The present invention is mainly processed by welding and machining. In the case of the problem of welding deformation existing in the cantilever structure product, the control of the installation position dimension accuracy within ±0.2 mm is realized, ensuring the installation requirements of the product. Brief Description of the Drawings

[0022] Figure 1 It is a schematic structural diagram of a radiator with a cantilever structure;

[0023] Figure 2 It is a schematic diagram of the weld formed by the cold-side outlet end cover and the core assembly, two cavity structures, and the bypass plate;

[0024] Figure 3 It is a schematic diagram of the position constraints and tolerance requirements in the design drawing of a radiator with a cantilever structure;

[0025] Figure 4 It is a schematic diagram of the tolerance requirements for welding the cantilever edge, the mounting base, and the bracket, and machining the mounting holes;

[0026] In the figure: 1. Core assembly; 2. Mounting base; 3. Cantilever edge; 4. Cold-side channel side; 5. Hot-side channel side; 6. Bypass plate; 7. Bracket. Detailed implementation manners

[0027] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. However, it should not be understood that the scope of the subject matter of the present invention is limited to the following embodiments. Without departing from the above technical idea of the present invention, all modifications, substitutions, and changes made according to common general knowledge and conventional means in the art are included in the scope of the present invention.

[0028] As Figures 1 to 4 shown, a cantilever structure radiator to be processed by the present invention is mainly composed of components such as a cold-side inlet end cover, a cold-side outlet end cover, a hot-side outlet end cover, a mounting seat 2, a core component 1, a bracket 7, and a bypass plate 6. Figure 1 Among them, at the bottom of the core component 1, there is a planar cantilever edge 3 extending outward from the core component 1. Four mounting seats 2 are welded to the lower end surface of the cantilever edge 3, and the core component 1 is located on the upper end surface of the cantilever edge 3. Two of the four mounting seats 2 are close to the end of the cantilever edge 3. Above these two mounting seats 2 and on the upper end surface of the cantilever edge 3, a bracket 7 is welded. The other two mounting seats 2 are close to the core component 1. The inlet and outlet ends of the cold-side channel side 4 of the core component 1 are respectively welded to the cold-side inlet end cover and the cold-side outlet end cover. Similarly, the outlet end of the hot-side channel side 5 of the core component 1 is welded to the hot-side outlet end cover. Figure 2 Among them, the welding situation between the cold-side outlet end cover and the core component 1 is shown. The cold-side outlet end cover divides its interior into two independent cavities through the internal partition board. Figure 2 Among them, the cavity closed by the bypass plate 6 on the left side of the cold-side outlet end cover is one of them. Figure 2 Among them, the cavity closed by the core component 1 on the right side of the cold-side outlet end cover is the other one. Figure 3 Among them, the size requirements of the mounting holes on the mounting seat 6 for the cold-side end cover and the hot-side end cover, as well as the flatness requirements of the end surface at the end of the mounting seat 6, are shown. Figure 3 And Figure 4 In [], "XX" represents the size. The design requires that the flatness of the mounting seat 2 in the radiator size is 0.5 mm, and the dimensional tolerance of the mounting hole position is required to be within ±0.2 mm; the mounting seat 2 is the main mounting surface and also the design reference. When the flatness of the mounting seat 2 and the hole position size meet the requirements, the dimensional accuracy requirements of the spatial positions of the inlet and outlet nozzles of the cold and hot side end covers with respect to the mounting seat 2 are within ±0.5 mm.

[0029] In order to achieve Figure 3 the technical requirements in [], the solution idea of the present invention is: weld the bypass plate 6 perpendicular to the core component and the bracket 7 with a large welding heat input on the cantilever edge under an open structure. The purpose is to reduce restraint on the one hand and to weld the welds that are likely to cause product deformation first, so as to release part of the welding stress through deformation. Finally, the present invention adopts the following processing method for the cantilever structure radiator:

[0030] Leave a margin on the end faces of the four mounting seats 2, such as Figure 2 , split the bypass plate 6 into upper and lower plates, namely the upper bypass plate and the lower bypass plate. First, weld the four mounting seats 2, the lower bypass plate, and the bracket on the cantilever edge 3 of the core assembly 1, so as to fully release the welding deformation. Then, perform stress relief annealing, and then use sheet metal correction to restore the deformation to the requirements in the design drawing. Then, as Figure 4 , use milling to machine off the margin on the end faces of the four mounting seats 2 to ensure that the flatness is not greater than 0.2 mm (leaving a deformation allowance for welding and sealing the other upper bypass plate finally), and mill mounting holes on the end faces of the mounting seats 2 as the reference for subsequent assembly and welding. Then, with the end faces and mounting holes of the mounting seats 2 as the reference, assemble the core assembly 1 onto the welding fixture and position the hot-side outlet end cover, the cold-side inlet end cover, and the cold-side outlet end cover, and then perform welding. Finally, weld the upper bypass plate (weld and seal the cavity with the core assembly 1, the lower bypass plate, and the cold-side outlet end cover) to form a complete cavity. Finally, achieve the technical requirements that the installation dimension error is within the range of 0.2 mm and the flatness of the mounting seat is below 0.5 mm.

[0031] As described above, it is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claimed rights.

Claims

1. A method for processing a cantilever structure radiator, wherein the cantilever structure radiator is mainly composed of a cold side inlet end cover, a cold side outlet end cover, a hot side outlet end cover, a mounting seat, a core assembly, a bracket and a bypass plate, wherein the bottom plane of the core assembly has a cantilever side extending toward the outside of the core assembly, characterized in that: Processing methods include: Step 1: Weld all mounting seats on the end surface of the cantilever side that is not the core component, and leave a machining allowance on the end surface of the mounting seat away from the cantilever side; Step 2: split the bypass plate into two pieces, wherein the piece far from the cantilever side is used as the upper bypass plate, and the piece close to the cantilever side is used as the lower bypass plate, firstly weld the two side edges of the lower bypass plate to the end face of the cantilever side corresponding to the core assembly side and the core assembly, respectively, and weld the bracket to the end face of the cantilever side corresponding to the core assembly side; Step 3, performing welding stress relief treatment on the parts welded in step 2; Step 4: Perform sheet metal correction on the parts that have been subjected to welding stress relief treatment in step 3 to correct the deformation of the cantilever edge and the mounting seat; Step 5: Perform margin cutting on the end face of the mounting seat away from the cantilever edge that has completed the sheet metal correction in step 4 to ensure that the flatness of the end face of all mounting seats away from the cantilever edge is less than the flatness requirement of the end face of the mounting seat in the design drawing, and process the mounting hole on the end face of the mounting seat; Step 6, using the end face and the mounting hole of the mounting seat milled in step 5 as the assembly and welding reference, assembling and welding the cold side inlet end cover, the cold side outlet end cover, and the hot side outlet end cover to the cold side inlet side, the cold side outlet side, and the hot side outlet side of the core assembly, respectively, wherein the welding of the cold side outlet end cover to the cold side outlet side of the core assembly also includes welding to the lower bypass plate; Step seven, weld the upper bypass plate to the lower bypass plate, the cold side outlet end cover, and the core assembly.

2. The method for processing a cantilever structure heat sink according to claim 1, characterized in that: In the step three, annealing is used to remove welding stress.

3. The processing method of a cantilever structure heat sink according to claim 1, characterized in that: In the step 5, milling is used to remove the excess of the end surface of the mounting seat away from the cantilever edge.

4. The method for processing a cantilever structure heat sink according to claim 1, characterized in that: In the step five, the mounting hole is processed on the end face of the mounting seat by milling.

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