Welding Methods and Applications in Automotive Industry

Welding is a necessary process in modern manufacturing and is widely used in automotive industry. The automotive engine, gearbox, axle, frame, body and compartment are six major assemblies of cars that are inseparable from the application of welding technology. In the manufacture of automotive parts, various welding processes are used,including spot welding, projection welding, seam welding, rolling spot (projection) welding, electrode arc welding, C02 gas shielded welding, argon arc welding, gas welding, brazing, friction welding, electron beam welding and laser welding. 

Among these processes, spot welding, gas shielded welding, and brazing have the characteristics of large production capacity, high degree of automation, high speed, low consumption, small welding deformation, and easy operation, making them particularly suitable for automobile body thin plate covering parts. Therefore, they are the most commonly used processes in automotive production. Spot welding accounts for about 75% of the investment cost, while other welding methods only account for 25%.

The automotive manufacturing industry is one of the industries with the widest range of welding applications. There are also many welding methods used and the applications are as follows:

1. Resistance welding

(1) Spot welding is mainly used for body assemblies, floors, doors, side panels, rear panels, front axles and small parts.

(2) Multi-spot welding is used for body panels, truck compartments, doors, engine covers, trunk lids, etc.

(3) Projection welding and rolling projection welding are used for body parts, shock absorber stems, brake hooves, screws, nuts and small brackets, etc.

(4) Seam welding is used for car body roof eaves, shock absorber seals, fuel tanks, mufflers and oil pans, etc.

(5) Butt welding is used for steel rings, exhaust and intake valve stems, cutting tools, etc.

2. Arc welding

(1) CO2 welding is used for welding car boxes, rear axles, frames, shock absorber stems, cross beams, rear axle shell tubes, drive shafts, hydraulic cylinders and jacks, etc.

(2) Argon arc welding is used for welding and repairing oil pans and aluminum alloy parts.

(3) Electrode arc welding is used for thick plate parts such as brackets, spare tire racks, frames, etc.

(4) Submerged arc welding is used for half-bridge casings, flanges, and pressure vessels of natural gas vehicles, etc.

3. Special welding

(1) Friction welding is used for automobile valve stems, rear axles, half shafts, steering rods and vehicle tools, etc.

(2) Electron beam welding is used for gears, rear axles, etc.

(3) Laser welding is used for cutting and trimming of body panels, gears, parts, etc.

4. Oxyacetylene welding

Used for repairing body assemblies.

5. Brazing

Used for welding of radiators, copper and steel parts, and carbide.