Stainless Stock Pot: Deep Drawn with a Bonded Base

A stock pot is deeper than it is wide, so it is deep drawn: a stainless steel blank is pushed into a die by a punch, with a blank holder to stop wrinkles, and redrawn through further dies until it is deep enough. Stainless spreads heat poorly, so many pots get an aluminium disc on the base: the disc and a thin stainless cap are tacked in place by resistance welding, heated (about 450–520 °C for aluminium) and bonded to the bottom in one blow of an impact press, around 5,000 psi in one patent. The handles are then riveted on, or sometimes spot-welded.