Complex sheet metal frame cabinet tailor-welding method

Abstract

The invention relates to the technical field of welding, and discloses a complex sheet metal frame cabinet tailor-welding method which comprises the following steps: S1, splitting: assembling an upper frame, a lower frame and a middle stand column according to a design structure of a frame cabinet; s2, bending is conducted, specifically, corners of the upper frame, the lower frame and the middle stand column are bent; s3, splicing is conducted, specifically, the upper frame, the lower frame and the middle stand columns are spliced into a frame, and the middle stand columns are clamped in the bent positions; and S4, welding is conducted, specifically, the spliced exposed parts of the upper frame, the lower frame and the middle stand column are welded. Through the four-step process of modular splitting, precise bending, mechanical interlocking and flat welding optimization, an innovative frame of mechanical positioning and then welding fixing is constructed, welding deformation is controlled from the source, the assembly consistency is improved, mechanical structure design and the welding process are deeply coupled, and the welding efficiency is improved. And a dual anti-deformation mechanism of physical interlocking constraint and welding heat input control is formed.

Description

Technical Field

[0001] This invention relates to the field of welding technology. Background Technology

[0002] In existing technologies, complex sheet metal frame cabinets are generally welded as a whole. However, this method generally suffers from problems such as "difficulty in controlling deformation, poor consistency, and low pass rate" when welding these types of frame cabinets. 1. When welding 1.5-3mm thin plates, the high temperature of welding generates significant thermal stress, which can cause the flatness deviation of the cabinet frame to reach 13mm and the torsional deformation to reach 3-5mm. It mainly relies on post-weld flame correction, but this will lead to a decrease in material hardness and incomplete elimination of internal stress. At the same time, welding in a closed space causes uneven heat distribution, which further aggravates the deformation and forms a vicious cycle of "welding-deformation-correction-re-deformation". 2. Relying on manual marking and alignment, the positioning error of a single component (±1-2mm) is amplified through multiple processes, resulting in a dimensional deviation of 5-8mm for products in the same batch. The lack of an effective guiding mechanism during assembly means that welders need to frequently adjust the weld gap to compensate for the error, which not only prolongs the working time but also makes it difficult to control the welding deformation due to the dynamic process of "adjusting while welding". This experience-based production mode results in a pass rate of only 65-75% during mass production and cannot meet the assembly tolerance requirement of ±0.5mm for precision cabinets. 3. In cabinet welding, 80% of the welds need to be completed in vertical or overhead positions. When welding overhead, the molten pool is prone to defects such as concavity and lack of fusion due to gravity. When welding vertically, it is difficult to control the electrode angle, and the undercut rate is as high as 30%, with the depth often exceeding the safety threshold of 0.5mm. At the same time, the traditional V-groove requires a large heat input, and the arc voltage is too high when welding overhead, which increases the porosity defect rate by 25%. These defects force 32% of the products to be repaired after welding, which seriously affects production efficiency. Summary of the Invention

[0003] The purpose of this invention is to provide a method for welding complex sheet metal frame cabinets. Through a four-step process of modular disassembly, precise bending, mechanical interlocking, and flat welding optimization, an innovative frame of "mechanical positioning followed by welding fixation" is constructed, which controls welding deformation from the source and improves assembly consistency.

[0004] To solve the above technical problems, the present invention provides a method for welding complex sheet metal frame cabinets, comprising the following steps: S1. Disassembly: Assemble the upper frame, lower frame, and middle column according to the frame cabinet design structure; S2, Bending: Bending the corners of the top frame, bottom frame, and middle column; S3. Assembly: Assemble the upper frame, lower frame, and middle column into a frame, with the middle column snapped into the bending position; S4. Welding: Weld the exposed parts of the splicing of the upper frame, lower frame, and middle column.

[0005] In step S4, welding is performed using a flat welding method.

[0006] In step S2, the corner bend has a wide opening for splicing guidance.

[0007] The bending angle is 45°.

[0008] The corner bend is achieved by chamfering the corners inwards.

[0009] The central column has an inward hook-shaped bend at its top corner to fasten the upper and lower frame.

[0010] The flat welding process involves placing the central column horizontally and then welding it.

[0011] The width of the corner bend is no greater than 1 / 3 of the width of the corresponding frame body.

[0012] In step S3, the upper and lower borders are symmetrically assembled.

[0013] Compared with existing technologies, this invention constructs an innovative framework of "mechanical positioning followed by welding fixation" through a four-step process of modular disassembly, precise bending, mechanical interlocking, and flat welding optimization. This framework controls welding deformation from the source and improves assembly consistency. It deeply couples mechanical structure design with welding process to form a dual anti-deformation mechanism of "physical interlocking constraint + welding heat input control".

[0014] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0015] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0016] Figure 1 This is a flowchart illustrating at least one embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the target frame cabinet of the present invention; Figure 3 yes Figure 1 A structural diagram showing the top border hidden after the splicing process. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the embodiments of this invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details are presented in the embodiments of this invention to facilitate a better understanding of this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments. The division of the following embodiments is for ease of description and should not constitute any limitation on the specific implementation of this invention. The embodiments can be combined with and referenced by each other without contradiction.

[0018] Example 1 like Figure 1 The method for welding a complex sheet metal frame cabinet, as shown, includes the following steps: S1. Disassembly: Assemble the upper frame, lower frame, and middle column according to the frame cabinet design structure; S2, Bending: Bending the corners of the top frame, bottom frame, and middle column; S3. Assembly: Assemble the upper frame, lower frame, and middle column into a frame, with the middle column snapped into the bending position; S4. Welding: Weld the exposed parts of the splicing of the upper frame, lower frame, and middle column.

[0019] Example 2 Based on Example 1, welding is performed using a flat welding method in step S4.

[0020] Furthermore, in step S2, the corner bend has a wide opening for splicing guidance.

[0021] Furthermore, the bending angle is 45°.

[0022] Furthermore, the corner bends are achieved by chamfering the corners inwards.

[0023] Example 3 Based on Embodiment 1, the top corner of the central column has an inward hook-shaped bend to fasten the upper and lower frame.

[0024] Furthermore, flat welding involves placing the central column horizontally before welding.

[0025] Furthermore, the width of the corner bend should not exceed 1 / 3 of the width of the corresponding main frame part.

[0026] Furthermore, in step S3, the upper and lower borders are symmetrically assembled.

[0027] Therefore, this invention achieves rigid interlocking based on modular pre-deformation design, dividing the cabinet into three parts: upper frame, lower frame and middle column. Through 45° inward chamfering and hook-shaped bending of the column top corner, the components form a mechanical interlocking structure similar to mortise and tenon when spliced. This design not only provides initial positioning accuracy through physical contact, but also forms a high-rigidity overall frame before welding through the constraint of "hooked bends tightening the frame," significantly reducing the degree of freedom of deformation during welding. The limitation that the width of the corner bends does not exceed 1 / 3 of the main body width ensures structural strength while avoiding stress concentration. The flat welding scheme of "welding after horizontal placement of the central column" transforms traditional vertical or overhead welding into a low-stress welding position, significantly reducing the impact of welding heat input on component deformation. Combined with the "symmetrical assembly of the upper and lower frames," the welding heat is evenly distributed on both sides of the structure, offsetting the bending moment generated by unilateral welding and realizing the principle of "symmetrical welding to reduce flexural deformation." The design of welding the exposed parts reduces the difficulty of welding in enclosed spaces and facilitates control of weld quality. The "wide-mouth design" of the bends serves as a splicing guide mechanism, solving the problem of accumulated errors during traditional manual alignment. By combining the fastening effect of hook-shaped bends, the positioning error of each component is controlled within the bending accuracy range (usually ±0.5mm), fundamentally improving the pass rate of mass production and shifting the quality control point from post-weld correction to the assembly stage.

[0028] Overall, the mechanical interlocking structure ensures that the components form a rigid whole before welding, thus constraining welding thermal deformation and greatly avoiding welding deformation caused by the imbalance between thermal deformation and rigid constraint. This solution, through pre-assembly and increased rigidity, controls deformation to within 30% of traditional processes. Simultaneously, the flat welding method reduces the impact of gravity on the molten pool during vertical welding. Combined with a small bevel design, the actual weld cross-sectional area is reduced by approximately 25% compared to a V-groove, further reducing welding shrinkage stress. Standardized bending and symmetrical assembly processes minimize the impact of human factors on quality. Wide-mouth guidance and hook-shaped fastening structures ensure that the assembly error of each cabinet does not exceed 0.3mm. Combined with stable process parameters for flat welding, this increases the product qualification rate from the industry average of 75% to over 95%. Exposed weld design and precise bending reduce post-weld correction workload by 80%. The horizontal welding posture shortens welding time per unit by 40%, while the reduced material waste and rework costs due to less deformation significantly improve production efficiency.

[0029] As can be seen, this invention systematically integrates three major elements: mechanical design (hook-shaped bending, wide-mouth guidance), assembly process (symmetrical assembly), and welding method (flat welding), forming a complete "prevention-control-optimization" solution. Its core innovation lies in replacing external tooling fixtures with rigid constraints from mechanical structures. This solves the problem of increased costs due to auxiliary supports and actively offsets welding stress through pre-deformation design. It is particularly suitable for thin-plate structural components with high dimensional accuracy and appearance requirements, such as communication cabinets and server chassis. Its "lock before welding" process provides a transformation path from "experience-based" to "parametric control" in the sheet metal welding field.

[0030] Those skilled in the art will understand that the above embodiments can be modified in form and detail in practical applications without departing from the spirit and scope of the invention.

Claims

1. A method for tailor-welding a complex sheet metal frame cabinet, characterized in that, The method comprises the following steps: S1, splitting: assembling the upper frame, the lower frame and the middle column according to the frame cabinet design structure; S2, bending: bending the corners of the upper frame, the lower frame and the middle column; S3, splicing: splicing the upper frame, the lower frame and the middle column into a frame, and the middle column is clamped at the bending position; S4, welding: welding the exposed part of the spliced upper frame, lower frame and middle column.

2. The tailor-welded blank method of claim 1, wherein, The step S4 adopts a flat welding method for welding.

3. The tailor-welded blank method of claim 1, wherein, In the step S2, the corner bending part has a wide mouth for splicing guidance.

4. The tailor-welded blank method of claim 3, wherein, The bending angle is 45°.

5. The tailor-welded blank method of claim 3, wherein, The corner bending is inwardly chamfered.

6. The complex sheet metal frame cabinet tailor welding method of claim 1, wherein, The top corner of the middle column has an inward hook-shaped bending for fastening the upper frame and the lower frame.

7. The complex sheet metal frame cabinet tailor welding method of claim 2, wherein, The flat welding is to place the middle column horizontally and then weld.

8. The complex sheet metal frame cabinet tailor welding method of claim 1, wherein, The corner bending part has a width not greater than 1 / 3 of the corresponding frame body part width.

9. The complex sheet metal frame cabinet tailor welding method of claim 1, wherein, In the step S3, the upper frame and the lower frame are symmetrically spliced.

Images