Butt welding — welding process at which details connect on all plane of their contact, as a result of heating. Depending on brand of metal, cross-sectional area of the connected details and requirements to quality of connection butt welding can be carried out in several ways: resistance, a continuous oplavleniye and an oplavleniye with heating. One of welding processes by pressure .
Welding by resistance is used for connection of details with cross-sectional area to 200 mm ². It is applied generally when welding a wire, cores and pipes from low-carbonaceous steel of rather small sections.
Welding by an oplavleniye is used for connection of details with cross-sectional area to 100000 mm ², such as pipelines, fittings of reinforced concrete products, butt compounds of profile steel. It is applied to connection of railway rails on the jointless ways, to production of dlinnorazmerny preparations from staly, alloys and non-ferrous metals. In shipbuilding it is used for production of anchor chains, coils of refrigerators of refrigerator vessels. Also welding by an oplavleniye is used in production of the cutting tool (for example, for welding of working part of a drill from tool steel with tail part from usual steel).