 While many welding applications are done in controlled environments such as factories and repair shops , some welding processes are commonly used in a wide variety of conditions , such as open air , underwater , and vacuums ( such as space ) . In open @-@ air applications , such as construction and outdoors repair , shielded metal arc welding is the most common process . Processes that employ inert gases to protect the weld cannot be readily used in such situations , because unpredictable atmospheric movements can result in a faulty weld . Shielded metal arc welding is also often used in underwater welding in the construction and repair of ships , offshore platforms , and pipelines , but others , such as flux cored arc welding and gas tungsten arc welding , are also common . Welding in space is also possible — it was first attempted in 1969 by Russian cosmonauts , when they performed experiments to test shielded metal arc welding , plasma arc welding , and electron beam welding in a depressurized environment . Further testing of these methods was done in the following decades , and today researchers continue to develop methods for using other welding processes in space , such as laser beam welding , resistance welding , and friction welding . Advances in these areas may be useful for future endeavours similar to the construction of the International Space Station , which could rely on welding for joining in space the parts that were manufactured on Earth . 
