A welding crewman in 2154
A Bajoran welder
A welder was a workman who specialized in combining materials, such as metal or plastic, with pressure and heat.
In 2151, a crewman served as welder in a section of Enterprise NX-01, moments after the ship was damaged by an unidentified alien vessel. (ENT: "Silent Enemy")
On February 12 2152, two members of Enterprise's crew worked as welders on Zobral's ship, in one of Enterprise's launch bays. (ENT: "Desert Crossing")
Later that year, Charles Tucker III and Maklii welded a dispersal cap onto an exposed well head from a deuterium pump. (ENT: "Marauders")
In 2153, a crewman served as a welder in Engineering aboard Enterprise after the ship suffered a primary injector flare and ended up in a polaric field. The welding was overseen by T'Pol. (ENT: "Similitude")
Aboard Columbia in 2154, two crewmen were doing some welding on the ship's bridge when the vessel's commanding officer, Captain Hernandez, gave Captain Jonathan Archer a guided tour of the bridge. One of the welders was at the fore of the bridge, whereas the other was in the situation room. (ENT: "Home")
In 2154, a crewman aboard Enterprise served as welder in a team which prepared a shuttlepod for a mission to the surface of Vulcan. (ENT: "Awakening")
In 2257, Crewman Harrington did some welding in a corridor aboard the USS Discovery while working on an electrical malfunction on deck 12. (DIS: "The Wolf Inside")
Welding was one of several methods Benjamin Sisko used in the construction of a Bajoran lightship. (DS9: "Explorers")
At one point in 2373, one of numerous Maquis refugees on Marva IV was welding. (DS9: "For the Uniform")
Once, in 2375, one of several Bajorans who followed Gul Dukat and the pah-wraiths was welding on the second level of Terok Nor's promenade. (DS9: "Covenant")