Resistance Arc/Spot Welding
About Resistance Welding
Resistance welding is a process that quickly and efficiently joins two or more thin sheets of metal. This welding process also allows both similar and dissimilar materials to be welded together with no shielding gasses or fluxes. Midwest Engineered Systems can automate resistance and spot welding processes into virtually any automation system. From small standalone systems to fully robotic automation, MWES custom designs each welding system for the customer’s specific needs.
How Resistance Welding Works
Resistance welding has wide applications in the metal fabrication and manufacturing industries. In all resistance welding processes, a strong current is passed through metals, heating them up and melting them together at predetermined points. These weld points will depend on the design of the welding workpiece and the positions of the electrodes used in the welding process. Some more common types of resistance welding include spot welding, seam welding, butt welding and projection welding.
Advantages of Resistance Welding
There are quite a number of advantages to using resistance welding. Among them are the following:
- A cleaner, less-polluted work environment
- It’s a simple process, easily integrated with automation and robotics, and does not demand pre-service training for welding teams
- Low-cost and capable of high-volume production
- Able to adapt to welds of similar and dissimilar metals
- Heat is concentrated and heat input intervals are short
- Typically does not need solvents or other materials; also has no need for shielding gases
Spot welding is the most frequently used type of resistance welding process. The welded joint is formed by pressing electrodes with pointed tips at welding locations to focus the proper current and heat to particular places on the metals to be welded. Spot welding can be easily automated and is extensively in the automotive industry for the production of car chassis parts and other sizable components. Spot welding is also used in the manufacturing of furniture and other household items.
Advantages of Spot Welding
Resistance Spot Welding (RSW) has several advantages that should be noted. Some of the most important ones include the following:
- Spot welding is fast, simple, and widely applicable
- No dangers from open flames
- No need for filler metals or fluxes to produce a join
- Automated robots can easily ramp up production by carrying out dozens to hundreds of spot welds within seconds depending on the weld components
- Metal sheets can be welded together simultaneously
Arc welding is the most common form of fusion welding used today. Arc welding uses an electric arc to create intense heat at upwards of 6500°F. At those temperatures, metals such as steel, stainless steel and aluminum can soften enough to be joined together. The electrical arc that creates such intense heat can be generated from either an AC or DC power source. When heated at high temperatures, metal will react chemically to oxygen and nitrogen which will liquefy at the point of contact. Once the metal has cooled and solidified, it will form a strong metallurgical bond between the two points of contact.
The two most common types of gas arc welding are Tungsten Inert Gas Welding (TIG) and Gas Metal Arc Welding (MIG). TIG welding uses a non-consumable tungsten electrode to create the arc with an inert shielding gas, such as argon or helium, to protect the weld pool from any airborne contamination. TIG welding is ideal for high precision welding and welding with sheet metal. MIG welding uses a process where a continuous consumable wire electrode is heated and fed into the weld pool. As with TIG welding, an inert gas, such as argon, is also used as a shielding gas to protect the weld pool from any airborne contamination. MIG welding is widely used in most industry sectors.
Building the future of manufacturing, together