A portable welding machine, sometimes called portable metal arc welding machine or portable spot welders, is utilized for welding together two or more pieces of metals using a filler material such as welding rod. The welder produces the arc that joins the two pieces and may be either direct or alternating current. There are four basic types of welding that are available in this process: spot welding, gas tungsten arc welding (GTAW), electro-statically-methedial (ESM), and flux cored arc welding (FCAW). This article provides information on each type of welding, with a brief description of the equipment needed for each. Portable welding machines have many advantages over stationary or fixed styles and can even be used as a part time work station.
A portable welding machine, sometimes called a portable metal arc welder or portable spot welding machine, is usually used for welding in high-relief situations, such as repair of mechanical or electrical components. When welding is performed in this manner, it is typically done in an area that does not have a lot of electrical or mechanical interruption. Portable units have many of the same features of a standard full-sized welders, including a seat, controls, accessories (switches, indicators, etc. ), electrode, shielding and fan. A common accessory is a trolley or rack that allows for the easy storage of the welder and its accessories.
Gas tungsten arc welding (GTAW) units employ a consumable gas, namely tungsten carbide, to produce the arc. A flexible metal base material, usually stainless steel, is charged on the welding rod and then pressed against the metal sheets that are to be welded. A welder seated at the base of the unit has the ability to adjust the electrode into a spot size before it is fed into the work.
This type of welding is typically used in areas that do not have a ready supply of welding equipment or are remote from a welding shop. Portable resistivity spot welder machines have been designed to handle sheet metal with less resistance than standard electrodes. A portable resistivity spot welder is different from most portable welders in that the welder has a smaller conductive path and uses the metal sheets as the source of conductivity. The welder heats only the areas that need welding, which eliminates the need for feeding the welder additional fuel or air.
One type of welding is the portable, or kva, welding system. These portable, or kva, welders can be either propane or compressed air powered. A welding gun is used to start the arc, and the welder positions the gun in the appropriate spot to start the arc. In most cases, this type of welding produces a single, steady arc. Smaller, manual portable welders use two triple-A batteries and one KVA power supply to operate.
Smaller portable welders also use propane or butane hybrid fuel to provide power for their electric lamps and fan. The electrical connections on these welders are often more appropriate for use in metal fabrication processes, because they are usually much hotter than traditional welding. This method of welding can produce a cleaner, more even weld because there are no stray hot spots on the surface of the metal. For this reason, many metal fabricators choose this method of metal fabrication.