11) Which is the welding machine designed to supply both A.C and D.C current for welding ferrous and non-ferrous metals using all types of electrode?

12) What is the name of distortion occurs in the weld direction?

13) What is the name of the the metal edge in an angle during welding and cutting operations?

14) Why the cylinder keys are not removed from the cylinder while welding?

15) Which process blow out the cylinder valve socket before connecting the regulator?