Patent ID: 6945567

Claim:
A pipe connecting unit for connecting a first pipe to a second pipe, the pipe connecting unit comprising: a bellows body made of elastomer material and having first and second ends; said bellows body having projecting fiance collars at said first and second ends, respectively; first and second annular holding flanges mounted behind corresponding ones of said flange collars and each of said holding flanges being configured to engage and grasp the flange collar corresponding thereto; first and second pipe mounted flanges mounted on corresponding ones of said first and second pipes; said first and second pipe mounted flanges being slip-on flanges joined to said first and second pipes at corresponding end portions thereof; said flange collars defining respective end sealing surfaces facing toward said slip-on flanges; each of said end sealing surfaces being partitioned in radial direction into at least inner and outer concentric annular sealing surfaces by a peripherally extending slot formed in the end sealing surface; only the outer annular sealing surface being in sealing contact engagement with the slip-on flange corresponding thereto when the holding flange is drawn toward and secured to the corresponding slip-on flange; and, a stabilization ring implanted in said slot at each end of said bellows body.