Abstract: A pipeline repair device is held in place against a pipeline while it is being welded. The device features an elongated body having a bottom surface provided with a recess to present a footprint surface which circumscribes the pipeline defect. The recess provides a stepped portion around the inner periphery of the footprint surface and a resilient gasket is received in this stepped portion. The thickness of the gasket is such as causes it to protrude below the footprint surface to provide a pressure tight seal between the repair device and the pipeline.