19. Bellows Expansion Joints

Prior to 1988, coverage of metallic bellows expansion joints in ASME B31.3 was very limited. Bellows were required to be designed in accordance with the rules for pressure design of unlisted components (par. 304.7.2) and the Standards of the Expansion Joint Manufacturers Association, Inc. (EJMA Standards). Appendix X was added in 1988, and has undergone several significant revisions in subsequent years. It provides specific Code coverage for metallic bellows expansion joints by adopting, with exceptions and additions, a widely used industry standard for expansion joints, the EJMA Standards.