Abstract:

         This paper surveys the characteristics, classification and the parameters matching for the technology of keyhole plasma arc welding. Keyhole plasma arc welding can cause a special keyhole, with which welding speed, workpiece thickness and welding efficiency will be all increased significantly. It can be generalized to constant, pulsed, variable polarity and special plasma arc welding, so it can satisfy special requirements of many different industries. This paper is quite significant to guide welding practice and increase productivity and the quality of welding joints.

Key words: plasma arc welding, high energy density welding, keyhole