Effective maintenance and repair are essential for efficient running of industries. welding, as a tool of maintenance and repair, plays a vitally important role in the functioning of all major industries. In general it may be said that practically any metal part which has broken or worn-out in service can be reclaimed by welding. In pact, one of the first uses of welding was to repair broken machinery and parts. what started out, as a process for making an emergency repair until a replacement could be obtained, has today become an economic necessity to conserve expensive materials and to reduce inventories.