Welding is called the technology of obtaining reliable permanent connections of parts made of solid material using plastic deformation and fusion of the material when heated.
All types of welding are divided by the fusion method. It can be carried out by local or general heating, as well as combinations thereof. Moreover, the resulting seam has the same characteristics (mechanical and physical) as the parts to be joined.
Today it is difficult to imagine any area in the construction sector where this technology would not be applied. It allows you to mount parts made of ceramic materials, plastics and various kinds of alloys and metals.
Types of metal welding can be divided into three main classes (depending on the type of energy used): mechanical, thermal, and their combination - thermomechanical.
One of the most commonly used methods remains arc, it is referred to as fusion welding. The base and filler metals are melted by creating an electric arc between the metal being welded and the electrode. A weld pool is formed and, as a result of subsequent crystallization of the cooling metal, a durable weld is formed.
When connecting too thick sheets, when it is not possible to warm the metal in one pass, the edges of the adjacent parts are chamfered before welding and a second pass is made. Then benign fusion occurs and a strong connection with a high-grade seam is obtained.
In second place in frequency of use can be put resistance welding. During the process, the junction is heated using electric current. Depending on the form of
connection, the types of welding are divided into: butt, relief, spot, suture, according to the method of Ignatiev and suture-butt. Resistance welding can be carried out by alternating, direct or pulsating current.
Of the modern varieties of welding processes, one can distinguish ultrasonic. It is used to join metals of very small thickness, as well as a number of plastics. This innovative method is widely used in the radio engineering, electrical and
electronic industries. And in the 70s, they even began to use it in medicine for "fusion" of bones in complex fractures, which significantly reduced the time of the disease, and hence the person’s incapacitated condition.
Such types of welding as contact, electric arc and a number of others have become widespread due to automation and mechanization of the production process.
This allowed us to perform a complex combination of structures with high technical and economic indicators.
Various types of welding can use ultrasound, laser radiation, friction, gas flame, etc. as a source of energy.
The strength and reliability of welded joints, new technological advances, modern convenient and practical equipment contribute to the widespread use of welding in various fields of construction production and repair work.