Abstract: An apparatus for launching objects, such as during casing cementing operations, in wells having dual gradient fluid systems or certain downhole internal diameter restrictions. A launching assembly is located below a dual gradient valve or other restriction. In one embodiment, control lines extend from the earth's surface to the launching assembly and control actuation of the launching assembly. In an alternative embodiment, a receptacle assembly is positioned above a dual gradient valve or other restriction, with control lines extending from the receptacle assembly to the launching assembly. A dart or other triggering object is launched from the earth's surface to the receptacle assembly in order to control actuation of the launching assembly.

Abstract: The present invention provides a cement shoe assembly for use on a string of tubulars in a well. In one aspect of the invention, the cement shoe assembly includes a housing having a lower portion with an enlarged inside diameter and a drillable cement shoe disposed therein. The shoe includes a weakened portion of material adjacent the enlarged inside diameter portion of the housing and ensures that as a cutting tool passes through the housing, all portions of the cement shoe are removed from the enlarged inside diameter portion, leaving a connection surface clear of debris for a subsequent tubular string. When a smaller tubular is expanded into the enclosed diameter portion of the housing, a connection is made therebetween without enlarging the outer diameter of the housing.

Abstract: The present invention provides a cement shoe assembly for use on a string of tubulars in a well. In one aspect of the invention, the cement shoe assembly includes a housing having a lower portion with an enlarged inside diameter and a drillable cement shoe disposed therein. The shoe includes a weakened portion of material adjacent the enlarged inside diameter portion of the housing and ensures that as a cutting tool passes through the housing, all portions of the cement shoe are removed from the enlarged inside diameter portion, leaving a connection surface clear of debris for a subsequent tubular string. When a smaller tubular is expanded into the enclosed diameter portion of the housing, a connection is made therebetween without enlarging the outer diameter of the housing.