Metal welding

According to the method of welding, there are machines for spot and relief and butt welding.

Spot contact welding is a welding process in which parts are joined at one or several points at the same time. The strength of the connection is determined by the size and structure of the welded point, which depend on the shape and size of the contact surface of the electrodes, the strength of the welding current, the time of its flow through the workpiece, the compression force and the condition of the surfaces of the parts to be welded. It is used to connect the thinnest parts of electronic devices for welding steel structures made of sheets in the automotive, aircraft and shipbuilding, agricultural machinery and other industries.

Relief welding is a welding process where the parts are joined at one or simultaneously several points with specially prepared projections-reliefs. This method is similar to spot contact welding. The main difference: the contact between the parts is determined by the shape of their surface at the joint, not by the shape of the working part of the electrodes, as in spot welding. Protrusions-reliefs are prepared in advance by punching or other means and may be present on one or both parts to be welded.

Relief welding is used in the automotive industry to attach brackets to sheet metal parts (e.g. to attach brackets to the hood of a car, to attach hinges for attaching doors to the cab); to connect fasteners – bolts, nuts and studs. In radio electronics it is used for joining wires to thin parts.

Butt welding – a welding process in which parts are joined across the plane of their contact, as a result of heat.

The maximum thicknesses to be welded:

• for sheet metal up to 5 mm (depending on steel grade);
• for parts of circular cross-section (wire) up to 12 mm.