A tensive cutting assembly includes a tensionable cutting member formed of a strip of material, typically metal, which is formed having a serpentine configuration. The staple gun includes an alignment slot for the insulated staple formed by projections from a magazine and the inner surface of a front cover. The force applied by a weight, presses a driving device against the broken pipe flange periphery, the force so applied distorts the ductile ring, thereby establishing a fluid-tight seal between the flange and the housing.