Abstract: The invention relates to a method and a device for blocking fluid in a pipe 1 onto which a positioning unit 2 is hermetically mounted and through which a hole is drilled in the pipe while maintaining a hermetic seal. An expandable body 8 is inserted into the pipe with the aid of a blocking implement 7 enclosed in support tube 9. The expandable body is expanded to temporarily block the flow of fluid in the pipe. The support tube has a supporting structure for supporting the expandable body against the flow of fluid during insertion into the pipe, after insertion, during expansion and after expansion. The support structure increases the capability of the expanded body to withstand the high pressure of the fluid.

Abstract: A device blocks the flow of fluid in a pipe so that work can be done on the pipe downstream of the device. The device includes an installation unit and a blocking unit. The installation unit is sealed against the ambient when mounted on the pipe to permit drilling a hole into the pipe and the blocking unit includes an expandable body which is passed through the installation unit and on through the hole in order to temporarily block the flow of fluid in the pipe. The expandable body has a larger diameter than the internal diameter of a channel in the installation unit. The blocking unit includes a rod mounted in the holder to which a manual force is applied for distending the expandable body before insertion so that the expandable body has a diameter less than the diameters of both the channel and the hole thereby facilitating passage of the expandable body through the channel and hole into the pipe.