A fit designated as 30H7/g6 is a Clearance fit.
In Clearance fit, the largest permitted shaft diameter is smaller than the diameter of the smallest hole, so that the shaft can rotate or slide through with different degrees of freedom according to the purpose of mating members.
The width of cut produced in gas cutting operation is known as Kerf.
A welding transformer is used to convert the A.C. main supply into an A.C. welding supply.
The narrow and thin part of the file which is connected to the handle is known as Tang.