Write briefly on the following forging processes: (i) Upsetting (ii) Drawing down (iii) Twisting (iv) Forming – NABTEB QUESTION

(i) Upsetting

This is a foregoing operation in which the material being forged is thickened or bulged and at the same time shortened. A bar of iron may be upset by heating the end to a welding heat; then placing its hot end down on the top of the anvil and striking the other end with a hammer. If the bar is long, it may be grasped with both hands and the end bounced or rammed upon the anvil.

(ii) Drawing down

This is the same thing as drawing out. It is a forging operation in which stretching or lengthening of the material to be forged is done by hammering. The tapered part of a flat cold chisel is an example of drawing out metal. It involves the metal being heated until it is bright red otherwise it will tear. To draw or sketch the metal, it is placed quickly on the horn of an anvil and strike with hammer.

(iii) Twisting

This is a forging operation in which flat or square metal fixed in a vice may be turned with a monkey wrench to form the figure below.

(iv) Forming

This is a forging operation in which certain shape is copied e.g. the forming of a ring on the horn of an anvil.