Welding specifications for sheet metal parts during welding processing

Sheet metal processing is generally a comprehensive cold working process for metal sheets with a thickness of less than 6 millimeters, which includes processes such as cutting, punching, cutting, laminating, folding, welding, riveting, splicing, and forming. Among them, welding is a very important link. There are some issues that need to be paid attention to in metal welding during sheet metal processing, including before welding, during the welding process, and welding standards. Today, the sheet metal processing manufacturer will take you to understand.

1、 Requirements before welding sheet metal parts:

1. All sheet metal raw materials must not be lower than the drawing requirements, otherwise they cannot be cut and produced.

2. The surface flatness of the welded section steel shall not exceed 0.2%, and the total curvature shall not exceed 0.3% of the total length.

Before welding sheet metal parts, all deformed parts must be straightened and leveled before welding.

4. Before welding begins, it is necessary to select suitable welding wires. Depending on different parameters such as part size, material thickness, and weld requirements, choose welding wires with varying thicknesses.

2、 Requirements during the welding process of sheet metal parts

1. The welding process must be strictly carried out in accordance with the drawings, technical requirements, and process requirements.

2. When welding, it is required to process the groove at the place where the groove is to be processed. If the workpiece does not have a groove or welded profile, the groove should be processed using a polishing machine or mechanical processing method according to the situation.

3. During welding, it is necessary to ensure that the external dimensions and positional tolerances of the workpiece meet the requirements of the drawing. Unless otherwise specified, the positional tolerances of non machined surfaces shall be executed according to IT15 level.

If material substitution is required during welding, written consent from the technical department is required, and the thickness of the sheet metal must also meet the requirements of the drawing. Otherwise, material substitution cannot be carried out.

5. The size of the weld seam during welding must be strictly in accordance with the requirements of the drawing. If the drawing does not clearly require the length of intermittent welding, welding should be carried out at intervals of 8 to 10 millimeters every 50 millimeters, and the distance between each welding point should be uniform and consistent.

6. Continuous welding seams must be straight and smooth, without obvious unevenness, and there should be no welding penetration, welding deviation, welding scar, porosity, undercutting, or other phenomena. The welding angle of the weld seam should be based on the drawing requirements, and if there are no requirements, the welding angle should be the small thickness of adjacent parts.

After welding is completed, each weld seam should be polished to remove both welding slag and burrs around it.

8. Some parts are not suitable for welding, such as parts that require bending on the drawing. Welding is not allowed without written consent from the technical department.

During the welding process of sheet metal parts, the parts that need to be struck can be gently hammered with a small manual hammer until the size meets the requirements. Do not use a hammer to strike vigorously on the sheet metal surface, otherwise it will cause damage and scrapping of the workpiece.

3、 Requirements and standards for post weld treatment of sheet metal parts

1. It is required that the weld seam of the sheet metal parts is smooth, showing a fish scale shape, and there should be no protrusions or unevenness.

2. It is necessary to ensure that the edges of the workpiece are flush and the surface is level. After welding, use sandcloth to re polish it to remove welding slag, welding points, and burrs with sharp edges and corners, and keep the weld seam flat and smooth.

3. On the plane of the box type workpiece, the height of the weld seam shall not be higher than the plane height. In principle, after applying putty, the weld seam should be completely covered.

4. For turnover parts and flat surfaces that do not need to be processed after welding, strict protection should be taken during welding to avoid arc damage or welding slag damage, and polishing should not be carried out casually on the premise of uniform welding seams.

5. For metal parts that require processing such as blueing and electroplating after welding, after welding meets the requirements, sandblasting treatment should be uniformly carried out. During the turnover process, strict protection should be taken to avoid scratches and bumps, and no further polishing treatment should be carried out.