Welding is a way of heating pieces of metal using electricity or a flame so that they melt and stick together. There are many kinds of welding, including arc welding, resistance welding, and gas welding. The most common type is arc welding. Anyone who is near arc welding needs to wear a special helmet or goggles because the arc is so bright. Looking at the arc without visual protection may cause permanent eye damage. It is also important to cover all your skin because it can give you something like a sunburn. Hot sparks from the weld can burn any skin that is showing. One kind of welding that does not use an arc is Oxy-fuel welding (OFW), sometimes called gas welding. OFW uses a flame to heat up the metal. There are other kinds of welding that do not use an arc.
Welding
History of welding
→ Main article: History of welding
See also: History of production engineering
Outline of the welding processes
The welding processes can be classified according to
Type of energy acting on the workpiece
- thermal energy, for example during fusion welding
- thermal energy with simultaneous or subsequent pressing together of the workpieces, for example in many resistance welding processes
- mechanical energy, for example in cold pressure welding
- mechanical energy that is converted into thermal energy, for example in friction welding
Type of base material
Purpose of welding
- Joint welding is used to join workpieces together
- Deposition welding is used to coat a workpiece; if the base material and the deposit material are different, a further distinction is made between the deposition welding of
- Armour
- Plating
- Buffer layers
physical process of welding
- Fusion welding is welding with localized melt flow, without application of force with or without filler metal of the same type (ISO 857-1). In contrast to brazing, the liquidus temperature of the base materials is exceeded. In principle, all materials that can be transferred to the molten phase can be joined by fusion welding. In many processes, additional material is added, for example in the form of a welding wire.
- Pressure welding brings the materials to be joined to the required welding temperature using different forms of energy, whereupon the joint is produced under the action of a force. Pressure welding does not require any additional material such as welding wire.
Degree of mechanization
- Manual welding
- than purely manual welding
- as partially mechanised welding, in which the filler metal and the auxiliary materials (shielding gases) are supplied mechanised, but the torch is moved manually,
- all-mechanical welding
- (fully) automated welding
Questions and Answers
Q: What is welding?
A: Welding is a process of heating pieces of metal using electricity or a flame in order to melt and join them together.
Q: How many different types of welding are there?
A: There are several different types of welding, including arc welding, resistance welding, gas welding, and Oxy-fuel welding.
Q: Which type of welding is the most common?
A: The most common type of welding is arc welding.
Q: Why is it important to wear special eye protection when near arc welding?
A: The arc produced during welding is very bright and looking at it without visual protection can cause permanent eye damage.
Q: Can welding cause burns?
A: Yes, hot sparks from welding can cause burns to any exposed skin.
Q: What is Oxy-fuel welding?
A: Oxy-fuel welding is a type of welding that uses a flame to heat up the metal instead of an electric arc.
Q: Are there any other types of welding that do not use an arc?
A: Yes, there are other types of welding that do not use an arc besides Oxy-fuel welding.