Abstract: A method of controlling the fluid pressure of an inflatable stopping bag used to block the fluid flow through a fluid conduit comprises pressurising the bag using a pressure regulator which operates to regulate the pressure of the bag as a function of the instantaneous pressure in the pipe upstream of the stopping bag.

Abstract: Apparatus for blocking the bore of a pipe (1) comprises a plurality of elongate shutter member (15-17) pivotably mounted to an elongate support member (3/3a) for insertion through a pre-drilled aperture (8) in the pipe wall. Actuating means (14) are provided for pivoting the shutter members (15-17) from an insertion configuration in which they substantially aligned with said support member (3a) and deployed configuration in which they are fanned out across the bore of the pipe (1). Each shutter member (15-17) is pivoted about a point (9) located towards one end thereof and towards the insertion end of the support member (3a) so as in use to lie between the axis of the bore of the pipe and the wall of the pipe (1) opposite the location of said aperture.

Abstract: A method of controlling the fluid pressure of an inflatable stopping bag used to block the fluid flow through a fluid conduit comprises pressurising the bag using a pressure regulator which operates to regulate the pressure of the bag as a function of the instantaneous pressure in the pipe upstream of the stopping bag.