Series EP Externally Pressurized Expansion Joints are used in straight runs of pipe to accommodate large amounts of thermal expansion. Typical applications would include steam systems, where extreme temperature differentials would cause thermal growth of the piping system. Series EP expansion joints are a packless, maintenance-free joint that incorporates an all stainless steel flexible bellows, a steel enclosure, with external and internal guide ring/sleeve to maintain alignment of the inner pipe.
The sleeve isolates the bellows from media, eliminating flow turbulence. External pressure is applied to the bellows via a gap between the internal flange and housing. Movement limitation is accomplished by means of an internal flange, and also guides the bellows along the longitudinal centerline. The external pressure keeps the bellows stable.