Sheet metal welding is an important part of the sheet metal processing process, which connects two separated metal objects into one by pressurizing, heating, or combining the two in a way that produces inter-atomic bonding force.
1. Classification of welding methods
According to the degree of heating in the welding process and the different characteristics of the process, sheet metal welding can be divided into fusion welding, pressure welding and brazing three categories.
•Fusion welding: the need to weld in the welding place of the local heating to the melting state that is, in the form of liquid welding. Common welding methods include gas welding, hand arc welding, submerged arc welding, electroslag welding and laser welding. These methods by heating the metal to melt, and then cooled and solidified to form a weld.
Pressure Welding:Pressurization is required, during which optional heating is applied to weld in solid form. Common methods of pressure welding include resistance welding, friction welding and diffusion welding. These methods weld by applying pressure that causes plastic deformation and interatomic diffusion of the metal.
Brazing: the use of lower than the melting point of the brazing in the material to be welded, filling the joints between the seam, is in the form of a combination of solid and liquid. Common brazing methods include soldering iron brazing, flame brazing and furnace brazing. These methods fill the weld seam by melting the brazing material, and then cool and solidify to form a welded joint.
2. Characteristics of welding technology
①Simplify the process: welding simplifies the casting, forging and other processes to reduce production costs and cycle time.
②. Good sealing: Welding the formation of the weld has a good sealing, especially for the need to seal the performance of the occasion.
③Material saving: welding can save metal materials, reduce the weight of the structure, improve the utilization of materials.
④Bimetallic structure: welding can realize the connection of bimetallic or multi-metallic structure, improve the overall performance of the product.
3. Common welding technology
A. spot welding: a commonly used rice gold welding method, by heating and pressure on the parts to be connected to achieve welding. Spot welding is usually used to connect sheet metal, especially for automotive manufacturing and other fields.
B. Soldering:A common manual welding technique that uses solder wire to join two metal parts. This method is suitable for smaller sheet metal processing parts, such as the assembly of electronic equipment.
C. TIG welding: a common gas-shielded welding technique that uses an inert gas (usually argon) to protect the weld from oxygen and other atmospheric contaminants. Argon arc welding is commonly used in sheet metal processing to connect stainless steel and aluminum alloys and other materials.
D. Gas Shielded Welding: A welding method that uses a shielding gas to protect the weld and provide additional heat. This technique is often used to weld larger sheet metal working parts.
Laser Welding:A high precision stainless steel sheet metal processing technique that uses a focused laser beam to melt and fuse metal parts. Laser welding is suitable for sheet metal processing projects that require a high degree of accuracy and detail.
4. Application areas of sheet metal welding
Sheet metal welding is widely used in various fields, including mechanical parts, automobiles, structural bodies, chemical plants, utensils, engineering and construction, metal fabrication, metal components, etc. With the increasing application of sheet metal materials in various industries, the application areas of sheet metal welding are also expanding. Especially in the field of automobile manufacturing aerospace, shipbuilding and large tractor manufacturing, sheet metal welding technology plays an irreplaceable role.
Frequently Asked Questions in Sheet Metal Welding
1. Welding Deformation
Problem: Due to uneven heating, sheet metal welding process is prone to deformation, especially when welding large areas of thin plate.
Solution: A fixture can be used to fix the sheet metal to reduce welding deformation. At the same time, segmented welding or symmetrical welding can also effectively reduce the deformation.
2. Weld cracks
Problem: Cracks may appear in the weld or heat-affected zone, mainly due to excessive cooling speed or welding stress.
Solution: control the cooling rate when welding, if necessary, can be preheated or post heat treatment of the weld.
3. Porosity
Problem: Porosity is due to the welding process gas trapped in the molten pool after cooling can not escape, affecting the strength and appearance of the weld.
Solution: Keep the welding area clean, choose the right flow of shielding gas to ensure a good welding environment.
4. Burn through
Problem: Especially when welding thin metal plates, too much current will cause the metal plate to be burned through.
Solution: Adjust the current and welding speed, if necessary, you can use spot welding method for welding.
5. Insufficient melting depth
Problem: Insufficient depth of fusion will lead to insufficient strength of the weld, and the weld may fall off.
Solution: Increase the welding current or slow down the welding speed to ensure sufficient depth of fusion.
In conclusion, sheet metal welding plays a vital role in numerous industries. By understanding various welding methods and applying effective techniques, you can improve the quality and efficiency of your welding projects. Proper selection of materials and safety precautions can ensure successful welding operations and maintain high standards in your work.
