Patent ID: 8925972
Filing Date: 2015-01-06
Classification: F16L

Abstract:
1. An in-line pressure balanced expansion joint for compensation of thermal expansion of piping and ducting of circular cross section with tie rods located inside the joint, which comprises one large, central expansion joint with stiffeners, a left sided expansion joint and a right sided expansion joint which are interconnected through respective casings and via the tie rods, characterized in that, the left sided expansion joint and right sided expansion joint comprise respective bellows whose inner diameter D 3 is greater than the outer diameter D 1 of the piping or ducting and on whose outer ends are tightly welded outer pipe spools that are tightly welded to the outer edges of external sides, which have the form of annular plates whose outer diameter is equal to bellows inner diameter D 3 and whose inner diameter is equal to the outer diameter D 1 of the piping or ducting, on the inner edges of the external sides, on the outside, are tightly welded further pipe spools for connecting the expansion joint to the piping or ducting, and on the inner ends of the left and rights sided bellows are tightly welded inner pipe spools that are tightly centric welded to the sides of the central expansion joint which comprises a bellows whose inner diameter D 4 is greater than the inner diameter D 3 of the left and rights sided bellows and whose ends are tightly welded to vet further pipe spools which are on the other hand tightly welded to the outer edges of the sides that have the form of annular plates whose outer diameter equals the inner diameter D 4 of the central bellows and whose inner diameter is equal to the outer diameter D 1 of the piping or ducting, whereby the tie rods do not obstruct fluid flow in the expansion joint.