Head (vessel)

A head is one of the end caps on a cylindrically shaped pressure vessel. A head is one of the end caps on a cylindrically shaped pressure vessel. Vessel dished ends are mostly used in storage or pressure vessels in industry. These ends, which in upright vessels are the bottom and the top, use less space than a hemisphere (which is the ideal form for pressure containments) while requiring only a slightly thicker wall. The manufacturing of such an end is easier than that of a hemisphere. The starting material is first pressed to a radius r1 and then curled at the edge creating the second radius r2. Vessel dished ends can also be welded together from smaller pieces. The shape of the heads used can vary. The most common head shapes are: