Retrofit remedial subsurface safety valve (SSSV)

摘要

A subsurface safety valve (SSSV) unit is installed in production tubing retrospectively and comprises a means to lock 10 and seal 12 with the tubing, a valve 13 and a hydraulic valve control line 14 extending inside the tubing from the top of the SSSV unit to the surface. The retrofit SSSV can be installed within a worn or damaged SSSV as a remedial valve. The hydraulic valve control line extends to the surface through the wellhead via a wellhead insert mounted inside the Christmas tree; the wellhead insert provides connections to allow normal control of the well with slots 27 providing connection to flow lines.