Patent ID: 6264401
Filing Date: 2001-07-24
Classification: F16L,Y10T

Abstract:
A method for facilitating pipeline transport of crude oil through an extended subsea pipeline, comprising:establishing a pipe-in-pipe subsea pipeline having a flowline for transporting well fluids in the form of an electrically conductive inner pipe concentrically surrounded by an electrically conductive protective outer pipe; establishing the pipe-in-pipe subsea pipeline further comprising:electrically isolating the inner pipe from the outer pipe along the length of the subsea pipeline by coating the outside of the inner pipe with an arc-resistant material; andelectrically heating the pipe-in-pipe subsea pipeline to maintain the temperature of the heavy crude oils produced above the point at which the viscosity will inhibit pipeline transport, said heating comprising passing electrical current along the exterior surface of the inner pipe and along the interior surface of the outer pipe;whereby the subsea pipeline maintains the heavy crude at a temperature at which it flows easily for pipeline transport.