Welding
Introduction:
- Welding is a fabrication process used to join materials, usually metals or thermoplastics.
- A process used to permanently joining two pieces of metal, usually by means of heat.
- During welding, the workpieces to be joined are melted at the joining interface and usually, a filler material is added to form a pool of molten material (the weld pool) that solidifies to become a strong
- Welding Unlike other joining processes, it permits the utilization of full strength of the material at the
Used for manufacturing to produce or repair of:
- Ships
- Storage tanks
- Pipelines
- Trains
- Automobiles
- Airplanes
- Home Appliances
- Bridges
Types of Welding:
Basically, welding may be classified into three types.
- Plastic welding: In the plastic welding or pressure welding process, the pieces of metal to be joined are heated to a plastic state and then forced together by external pressure. These welding are also known as liquid-solid welding process. This procedure is used in forge welding and resistance welding.
- Fusion welding: In the fusion welding or no pressure welding process, the material at the joint is heated to a molten state and allowed to solidify. These weldings are also known as the liquid state welding process. This includes gas welding, arc welding, thermite welding, etc.
- Cold welding: In this welding process, the joints are produced without application of heat, but by applying pressure which results in diffusion or inter-surface molecular fusion of the parts to be joined. It is also known as the solid-state welding process. This process is mainly used for welding nonferrous sheet metal, particularly aluminum and its alloys. This includes ultrasonic welding, friction welding, Explosive welding, etc.
