Electro-mechanical wireline anchoring system and method

Abstract

An electro-mechanical wireline assembly as shown for anchoring a wireline tool string in place during a wellbore under balanced well conditions. The assembly includes an upper connection for connection to the wireline leading to the well surface and a lower connector for engaging a wireline tool. An outer mandrel is attached to the lower connector. An inner mandrel is carried at least partly within the outer mandrel and is capable of axial movement within the outer mandrel. A slip gripping assembly is carried on the outer mandrel and includes slips which are normally biased radially inward but which can be moved radially outward for engaging a surrounding wellbore and holding the wireline tool string in place. An electric motor assembly is carried on the wireline assembly between the upper and lower connectors. The electric motor assembly is actuable by an electric current supplied from the well surface through the wireline to effect axial movement of the inner mandrel relative to the outer mandrel to expand the gripping slips in a radial direction between a start position and a set position. The electric motor assembly can be switched in order to reverse the direction of axial movement of the inner mandrel relative to the outer mandrel to retract the gripping slips and return the slips to the start position. A back-up manual release means is provided for manually retracting the gripping slips radially inward upon completion of wellbore operations.