Experimental Investigation of Spring Back and Wrinkling Phenomena in Square Pipes during Bending

Bending operation is one of the crucial steps in producing a variety of industrial products. The objective of this work is to design and fabricate a pipe bending die for making square shaped pipes. Design of the die is done in such a way that it can replace the circular pipe bending die in the metal forming lab of CBIT. This increases the utility of the machine and helps to calculate the bending load, spring back and wrinkling effect for a given size and thickness of square pipe. In this work, an attempt is made to investigate the effect of bend angle on spring back by varying the thickness of square pipe. Also, an effort is made to reduce the wrinkling effect occurring in square pipes during bending process. The studies reveal that spring back increases with increase in bend angle and with increase in pipe thickness spring back decreases.