Allowable Shape Deviation in a Pressurized Cylinder

Abstract

Presence of initial shape imperfection causes additional bending stresses to be developed in a pressurized cylinder. Although the bending stress will initially increase with pressure, it will finally settle down to a certain value. This article derives the maximum bending stress associated with the geometric shape imperfection. It also discusses the implication of this additional bending stress on the design stress and allowable shape tolerance. Finally, it is concluded that a 1-percent diametral deviation, as commonly specified by most design codes, is adequate and sound for the internally pressurized cylinder.