Abstract: This invention relates to a release/anti-preset mechanism for retrieving a down-hole tool and for preventing premature actuation of the tool during insertion thereof into a subterranean well-bore. Release mechanisms for retrieving down-hole tools are known and can be divided into three main types: shear release systems, conventional wireline/coil tubing/drill pipe (WL, CT, DP) actuated systems and hydraulically activated systems. Known mechanisms suffer from a number of problems. Accordingly the present invention provides a retrievable down-hole tool (5) having a release/anti-preset mechanism comprising first and second members (10, 15) radially releasably engagable by a third member (20) which controls radial deflection of one of the first or second members (10, 15).

Abstract: A setting tool for setting of any of a variety of down-hole devices used in petroleum/gas producing wells. A known setting tool employs an explosive charge. A disadvantage of this tool is that due to safety considerations, when such tools are in use, radio silence must be maintained on the drilling rig. Another known setting tool employs hydraulic forces. A number of problems exist with known tools.