Welding is commonly called the technology of obtaining reliable one-piece joints of parts made of solid material, using plastic deformation and fusion of the material when heated.
All types of welding are divided according to the fusion method. It can be carried out by local or general heating, as well as their combination. 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 industry where this technology would not be used. It allows you to fasten parts made of ceramic materials, plastics and various 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 is arc welding, it is referred to as fusion welding. The base and filler metal are melted by creating an electric arc between the metal to be welded and the electrode. A weld pool is formed and, as a result of the subsequent crystallization of the cooling metal,a strong seam is formed.
When joining too thick sheets, when it is impossible to heat up the metal in one pass, before welding, the edges of the adjacent parts are beveled and a second pass is made. Then a benign fusion occurs and a strong connection with a high-quality seam is obtained.
Resistance welding can be put in second place in terms of frequency of use. During the process, the connection point is heated using electric current. Depending on the form of the connection, the types of welding are divided into: butt, relief, spot, seam, according to the Ignatiev method and seam-butt. Contact welding can be carried out with alternating, direct or pulsating current. Ultrasonic welding can be distinguished from modern varieties of welding processes. 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, electrical and electronic industries. And in the 70s, they even began to use it in medicine for "fusion" of bones in case of complex fractures, which significantly reduced the time of illness, and hence the incapacitated state of a person.
Such types of welding as resistance, electric arc and a number of others have become widespread due to the automation and mechanization of the production process.
This made it possible to perform a complex connection of structures with high technical and economic indicators.
Various types of welding as a source of energycan use ultrasound, laser radiation, friction, gas flame, etc. Strength and reliability of welded joints, new technological achievements, modern convenient and practical equipment contribute to the widespread use of welding in various areas of construction production and repair work.
