Patent ID: 7607485
Filing Date: 2009-10-27
Classification: E21B

Abstract:
1. A wellhead assembly, comprising: a wellhead member having a tubular sidewall defining a bore; a tubing hanger landed in the bore for supporting a string of tubing, the tubing hanger having a production passage for fluid communication with the interior of the string of tubing; a tubing hanger seal surrounding the tubing hanger and sealing an exterior surface of the tubing hanger to the bore; a tubing hanger tubing annulus passage within the body of the tubing hanger extending alongside the production passage from a lower port on a lower portion of the tubing hanger to an upper port on the exterior surface of the tubing hanger below the tubing hanger seal; a wellhead member tubing annulus passage within the sidewall of the wellhead member, having a lower end at the bore below the tubing hanger seal for communication with the upper port of the tubing hanger tubing annulus passage and an upper end at the bore above the tubing hanger seal; and wherein the tubing hanger tubing annulus passage and the wellhead member tubing annulus passage are sized to enable circulation of fluid along a path down the string of tubing and up the wellhead member tubing annulus passage.