The purpose of this thesis was to create mechanization plans for backing gas which is required in plasma welding. The project was commissioned by YIT Teollisuus Oy from the town of Leppävirta. The company is specialized in manufacturing tanks and pipelines of such materials as stainless steel, acid-proof steel and duplex stainless steel. The aim of this thesis was to find out in which situations mechanization is needed and to make a working prototype to mechanize the backing gas.

Employees of the company were interviewed concering plasma welding and backing gas problems. Author’s current knowledge about plasma welding was completed with relevant literature. Based on the interviews and meetings and research of problems in backing gas, a solution was found to the client company.

As a result of this thesis solutions to problems in backing gas were obtained and a working prototype to mechanize backing gas was developed. This mechanization solution helps to decrease the production costs of products and it improves both the work ergonomic and safety issues.