Welding of metal, advantages and types
Widely used in the construction and everyday life were welded joints. Welding of metal has such advantages in comparison with other ways of joining parts:
- saving material, there is no need to use additional fasteners;
- the design is more reliable, all welded joints are designed for the current load;
- more rational use of the material, it is not necessary, as with casting in molds, to install the gates, and when machining, give additional allowances;
- Reducing the complexity of manufacturing parts and components of structures due to the rational use of metal of the required thickness.
Welding of metal is carried out by such weldingmaterials: electrodes, wire, rods. Depending on the material of the welded product, they can be made of carbon steels, aluminum alloys, tungsten non-consumable electrodes, and electrodes for connecting cast iron.
The main types of welded joints: angular, plug, tie, butt, lapping, electric seals (contact welding).
Ways of making connections:
- manual welding of metal - is usual or has a deep penetration;
- Automatic - arc under a layer of flux, in a carbon dioxide environment, electroslag;
- semi-automatic - in the environment of protective gases and under a flux.
By the way the seams are arranged in space, theythere are: ceiling, vertical, horizontal and bottom. In length - solid and intermittent. Electro-rivets and intermittent seams are used in joints that do not require tightness. Solid seams are used, if required by the design documentation. When it is necessary to perform a complete test, the sealing of the seam is checked by ultrasonic method or kerosene.
Welding of metal end-to-end thickness up to 8 mm is performed without cutting edges. Over one-sided or two-sided edge cutting is done, depending on the thickness of the material and the design purpose.
Welding of sheet metal is carried out by longitudinalor transverse sutures, first the second, and then the first, are cooked. The seam is applied from the top to the bottom to avoid an influx when it is applied. The gaps between the elements should be approximately 1 mm.
When welding of thin metal is performed, forIn order to avoid deformation of the material, compulsory wear of the structure is performed. In addition, it is necessary to superimpose the seam at first continuous, and then fill the missed places.To prevent metal burning,joint should be strictly maintained technology and use the appropriate electrodes or a suitable wire diameter. All butt seams are performed on the lead-out slats.
For automatic welding of pipes, boxes, sheetsplasma surfacing is used. The thickness of the welded elements is from 0.5 mm to 5 mm. The main materials for plasma technology are stainless, galvanized, low-carbon steel.
Contact spot mating is used forblack or non-ferrous metals overlap. It is used in the manufacture of ventilation, in fixing the ends of pipes, in the manufacture of shaped products. With a contact connection, equipment is used that is easy to set up and easy to operate.