Tubing hanger apparatus and wellhead assembly for use in oil and gas wellheads

Abstract

A tubing hanger apparatus includes a tubing hanger with a plurality of segments thereon that engage an annular groove of a tubing head thus preventing the tubing hanger from sliding down a well. The internal diameter wellhead bore is consistent from the master valve downward to the production casing. The tubing hanger has a plurality of annular seals which are expandable after insertion into the tubing head. A plurality of lock screws both expand the seals as well as prevent any further movement of the tubing hanger. The tubing hanger apparatus is situated below a master valve. Thus, coiled tubing or jointed tubing can be run down the well and landed below the master valve. The tubing hanger contains a back pressure valve, thus the master valve can be opened without releasing the formation pressure within the live well.

1 . A tubing hanger apparatus for a wellhead, comprising:
 a tubing head having a bore with a recess in the bore surface and a shoulder protruding from the bore surface below the recess;   a tubing hanger insertable within the tubing head bore, the tubing hanger having an upper end, a lower end, connectable to a coiled tubing or jointed tubing string, and between the upper and lower ends: a bore contact surface for slidably contacting the bore surface, an engagement surface below and laterally recessed from the bore contact surface, and an actuation surface below and laterally recessed from the bore contact surface;   an engagement segment slidable along the engagement and actuation surfaces of the tubing hanger,   an actuation segment slidable along the actuation surface of the tubing hanger below the engagement segment;   wherein when the tubing hanger is located in a locked position in the bore, the actuation segment contacts the bore shoulder, the engagement segment is located onto the engagement surface by the actuation segment and engages the bore recess.   
   
   
       2 . A tubing hanger apparatus as claimed in  claim 1  wherein the bore contact surface, engagement surface, and actuation surface are annular and extend around the tubing hanger. 
   
   
       3 . A tubing hanger apparatus as claimed in  claim 2  wherein the actuation and engagement segments are annular, and are slidable along and surround the tubing hanger. 
   
   
       4 . A tubing hanger apparatus as claimed in  claim 3  wherein the engagement segment is expandable, wherein the engagement segment is in an unexpanded position when surrounding the actuation surface and in an expanded position when surrounding the engagement surface. 
   
   
       5 . A tubing hanger apparatus as claimed in  claim 4  wherein the engagement segment has first and second ends facing each other. 
   
   
       6 . A tubing hanger apparatus as claimed in  claim 2  wherein the tubing hanger further comprises:
 a sealing surface above and laterally recessed from the bore contact surface;   a compressible annular seal surrounding the sealing surface such that the seal does not protrude from the bore contact surface when uncompressed; and   a seal compressor movable between an uncompressed position wherein the seal is uncompressed, and a compressed position wherein the seal is compressed and protrudes beyond the bore contact surface to contact the bore surface when the tubing hanger is inserted inside the bore.   
   
   
       7 . A tubing hanger apparatus wherein the seal compressor is annular and surrounds the tubing hanger adjacent the seal, the seal compressor being slidable along the tubing hanger between the uncompressed and compressed positions. 
   
   
       8 . A tubing hanger apparatus as claimed in  claim 7  wherein the tubing head further comprises a seal compressor engagement means operable to engage the seal compressor when the tubing hanger is in the locked position and move the seal compressor between compressed and uncompressed positions. 
   
   
       9 . A tubing hanger apparatus as claimed in  claim 1  further comprising a lock screw operable to engage the tubing hanger when in the locked position. 
   
   
       10 . A tubing hanger apparatus for a wellhead as claimed in  claim 1  further comprising an annular spiral lock located on the tubing hanger below the actuation and engagement segments and for preventing the actuation and engagement segments from sliding off the tubing hanger. 
   
   
       11 . The tubing hanger apparatus for a wellhead as claimed in any of  claims 1  to  10  further comprising a master valve located above the tubing hanger apparatus and having an internal diameter equal to or greater than that of a production casing attached to the wellhead without reducing the internal diameter of the tubing head. 
   
   
       12 . A wellhead assembly comprising:
 a blowout preventer;   an adaptor flange connected to the blowout preventer;   a master valve connected to the adaptor flange; and   a tubing hanger apparatus as claimed in  claim 1  wherein the tubing head is connected to the master valve.   
   
   
       13 . A wellhead assembly as claimed in  claim 12  further comprising:
 the addition of a swedge attached at a first end to the tubing head and a top section attached to a second end of the swedge.