Sveising

Sveising, or welding, is a fabrication process that joins materials—primarily metals, and in some cases plastics—by heating the surfaces to the point of fusion, by applying pressure, or by a combination of both, producing a permanent joint. Fusion welding melts the base materials and often filler material; solid-state welding joins without complete melting.

Common welding processes include arc welding, such as shielded metal arc welding (SMAW), gas metal arc welding (GMAW or MIG), flux-cored arc welding (FCAW), and gas tungsten arc welding (GTAW or TIG); gas welding using a combustible gas such as oxy-acetylene; submerged arc welding (SAW) for thick sections; and advanced methods like laser beam welding, electron beam welding, friction welding, friction stir welding, and ultrasonic welding for specific materials and applications.

Materials most commonly welded are steels, stainless steels, aluminum, and titanium, with plastics joined by specialized techniques. Joints can be butt, fillet, lap, groove, or corner welds, chosen according to load, geometry, and production constraints.

Safety and quality are central to welding practice. Hazards include heat, UV radiation, fumes, burns, and electric shock, necessitating protective equipment such as a welding helmet with an appropriate shade, gloves, protective clothing, and good ventilation. Quality control involves procedures and qualifications, including welding procedure specifications (WPS) and qualification records (PQR), and adherence to standards such as ISO 3834 for quality requirements, EN ISO 15614 for procedure qualification, or AWS codes in North America.

Applications span construction, shipbuilding, pipelines, automotive and aerospace manufacturing, and general metal fabrication, making welding a foundational technique in modern industry.