Tubing hanger with flapper valve

摘要

A tubing hanger including a tubing hanger body having a tubing string which is adapted to be supported in the bore of the wellhead housing wherein the apparatus comprises a flapper valve disposed in or below the tubing hanger, wherein the valve further comprises a flapper valve having a flapper valve closure member substantially in the form of a concave spherical segment defining an annular valve seat concentric with the tubing for the flapper valve; a flapper plate disposed in the valve chamber for rotatable movement from a valve position in which the flapper plate is removed from the annular valve seat to a valve position in which the flapper plate extends transversely across the flow passage for the flapper valve and forms a sealing engagement with the annular valve seat and the sealing surface is substantially in the form of a convex spherical segment, wherein the convex spherical segment is disposed intermediate between the first and second planar surfaces.