Norvell & Associates
Insulated tubing joint
 A concentric insulating tubular conduit string, including one or more joints with concentric tubular members is disclosed. A concentric walled joint of the type disclosed herein is especially adapted to form a separation joint when incorporated in the tubular string. An insulating conduit incorporating one or more integral separation joints of the type disclosed could be employed for the delivery of a heated fluid, such as steam, through the conduit to the producing formation therebelow. The inner and outer tubular members of the separation joint may be prestressed in tension and compression between axially spaced coupling members used to join the separation joint to the rest of the tubular conduit. A hermetically sealed annular insulating cavity is formed between the inner and outer tubular members. This joint can be separated by merely severing the tensile loaded tubular member and upon severance of this separation joint the conduit extending thereabove can be removed from a subterranean well. 
Baker Oil Tools, Inc.
E F E
E21B F16L E21B
inventional inventional inventional
David M. Yung J.
Anderson Kim