Abstract: An apparatus can include a downhole tool having a fluid outlet connectable to a fluid inlet to define a flow path via a hollow interior of the tool, and a valve member capable of opening and constricting or closing the flow path. The apparatus further includes pipe within which a part of the tool is located, the tool being sealed with an interior of the pipe, preventing fluid flow in the pipe via the part of the tool. The pipe includes an openable valve for permitting flow of fluid from the pipe interior via another flow path interconnecting the pipe interior and outside. The valve is normally closed. When the valve member constricts or closes the first flow path, fluid pressure in the pipe increases to cause opening of the valve and venting of pressurized fluid from within the pipe to the outside via the second flow path.

Abstract: An apparatus can include a downhole tool having a fluid outlet connectable to a fluid inlet to define a flow path via a hollow interior of the tool, and a valve member capable of opening and constricting or closing the flow path. The apparatus further includes pipe within which a part of the tool is located, the tool being sealed with an interior of the pipe, preventing fluid flow in the pipe via the part of the tool. The pipe includes an openable valve for permitting flow of fluid from the pipe interior via another flow path interconnecting the pipe interior and outside. The valve is normally closed. When the valve member constricts or closes the first flow path, fluid pressure in the pipe increases to cause opening of the valve and venting of pressurized fluid from within the pipe to the outside via the second flow path.