These articles contain information about some of the less commonly used welding processes, such as flash welding, electron beam welding, electro-slag welding, friction welding, carbon arc welding, SAW welding, plasma arc welding, laser beam welding, thermit welding, etc.
This article discusses about a few welding processes that are not as commonly used as say, SMAW, GTAW, SAW, etc. Although a large number of variations of each conventional process exist, this article limits to a discussion of only electron beam welding, friction welding, thermit welding, laser welding and flash welding. Electron Beam Welding In … Read more
Resistance welding is the name given to a group of welding processes in which coalescence between two metals is obtained by heat arising out of resistance posed by the work-piece to the flow of current. Pressure is generally applied to secure the joint firmly. The work-piece is a part of the electric circuit, through which … Read more
SAW, short for submerged arc welding is a welding process in which joining of metal is obtained by striking an electric arc between a consumable wire electrode and the work-piece. Shielding is provided by a blanket of flux which covers the arc completely. In other words, the arc is submerged under the flux. The process … Read more
CAW – short for carbon arc welding, is a welding process in which fusion is obtained by heat produced by striking an arc between a carbon electrode and the work-piece. Shielding is not used. Pressure may or may not be used. Filler rod also may or may not be used. The main difference between the … Read more
When two metals are closely pressed together, and an electric current is passed through them – they offer an electric resistance to the flow of current. This resistance is greater than the one if the current was flowing through a continuous metal. The resistance to current causes heat to be generated between the two metals. … Read more
PAW, short for Plasma Arc Welding is a type of metal joining process in which coalescence is obtained by heating the work-piece with a constricted arc. The constricted arc can be struck in two ways: one, between the tungsten electrode and the work-piece. This is called a transfer arc. Two, the arc is struck between … Read more
Friction welding is a solid-state welding process that produces coalescence of materials by the heat obtained from mechanically-induced sliding motion between rubbing surfaces. The work parts are held together under pressure. This process usually involves the rotating of one part against another to generate frictional heat at the junction. When a suitable high temperature has been … Read more
In thermit welding, the thermit material is a mechanical mixture of metallic aluminum and processed iron oxide. Molten steel is produced by the thermit reaction in a magnesite-lined crucible. At the bottom of the crucible, a magnesite stone is burned, into which a magnesite stone thimble is fitted. This thimble provides a passage through which … Read more
Flash welding is a resistance welding process that produces coalescence simultaneously over the entire area of abutting surfaces by the heat obtained from resistance to electric current between the two surfaces, and by the application of pressure after heating is substantially completed. Flashing and upsetting are accompanied by the expulsion of metal from the joint. This … Read more
Laser beam welding (LBW) is a welding process that produces coalescence of materials with the heat obtained from the application of a concentrated coherent light beam impinging upon the surfaces to be joined. The focused laser beam has the highest energy concentration of any known source of energy. The laser beam is a source of electromagnetic … Read more