Abstract

A coupling of the disclosure connects and seals inner and outer pipes having an interfitted lap joint by the provision of a coupling band that is stretched about the joint in a clamping relationship over the outer pipe end and a seal ring engaged with the inner pipe. A roundish sleeve portion of the band is stretched by deformation of a radially projecting channel portion thereof which receives a pair of axially spaced reaction members in respective axial alignment with the seal ring and the outer pipe end. A clamping device of the coupling includes tightening members on opposite sides of the band channel portion and cooperable nut and bolt sets that move the tightening members toward each other to deform the band channel portion against the reaction members and thereby stretch the sleeve portion over the joint. A strip of sealing material is bonded to each reaction member and engaged with the outer pipe end and the seal ring. Circumferential ends of the seal ring have respective ramp surfaces interengaged with each other at an angularly spaced location from the band channel portion. During the deformation of the band channel portion, the seal ring ends are moved axially relative to each other to maintain a sealed condition between the ring ends.