Systems and Methods for Catastrophe Mitigation for Deep Water Oil Drilling during Blowout Preventer Failure

Abstract

Disclosed herein in example embodiments is a simple Drill-Through-Equipment (DTE) system for deep water drilling of oil, to intervene in the event of Blowout Preventer (BOP) failure, and mitigate spill disaster. Example embodiments of systems and methods of failed BOP intervention, and oil spill disaster mitigation disclosed herein may be used to mount a housing within the existing BOP below the blind shear ram, whereby the failed BOP is made accessible just below the blind shear ram through access ports, opening or closing in the housing. Through these ports blowout is diverted, thus protecting the rig. Through these same ports access is granted to the drill pipe allowing external manipulation or cutting of the drill pipe in effort to render the BOP operational. Once this is accomplished, the access ports are closed, and normal BOP and/or drilling operations are resumed. Example embodiments integrate and make use of existing BOP machinery.

Therefore, at least the following is claimed: 
     
         1 . A disaster mitigation system for deep sea oil drilling, to mitigate disastrous consequences caused by blowout emergencies due to blowout preventer (BOP) failure, the system comprising of
 (a) a housing assembly;   (b) a annular ram positioned within the housing, the ram configured to slide and abut a surface on one end of the housing, and open and close side openings in the housing;   (c) a locking mechanism configured to lock the annular ram surface against the housing surface into closed position;   (d) a guiding mechanism configured to align the locking mechanism to the annular ram locking features;   (e) a hydraulic chamber within the housing to slide the annular ram into closed or open position; and         
     
     
         2 . The disaster mitigation system of  claim 1 , wherein the housing assembly comprises:
 (a) an upper housing part;   (b) a lower housing cap part;         
     
     
         3 . The disaster mitigation system of  claim 2 , wherein the upper housing part comprises:
 (a) An integrated ram case on which to mount a pair of BOP blind shear rams, or any other rams of choice;   (b) large openings on the side of this housing;   (c) stiffener geometry to provide proper stiffness of the housing;   (d) circumferential grooves on the inside diameter into which hydraulic seals are installed;   (e) the inside diameter having a longitudinal groove on in which a guide pin slides;   (f) the housing having a drilled hole through which a guide pin is installed into the annular ram;   (g) two drilled holes to be tapped as needed for any hydraulic coupling and fluid passage;   (h) a second, larger inside diameter forming the wall of the hydraulic chamber for the annular ram;   (i) an axial hole through, equal in diameter to the BOP drill column; and   (j) a series of holes drilled through the bottom circular flange of the housing to receive a plurality of threaded fasteners for affixing it to the lower housing cap.   
     
     
         4 . The disaster mitigation system of  claim 2 , wherein the lower housing cap part comprises;
 (a) An integrated ram case, i.e. a large boss, on which to mount a pair of BOP casing shear rams, or any other rams of choice;   (b) a plurality of tapped holes to which threaded fasteners affix to it the upper housing part;   (c) a cylindrical boss onto which the annular ram slides;   (d) the boss having grooves recessed into it to retain hydraulic seals which isolate well pressures and hydraulic pressures; and   (e) an axial hole through, equal in diameter to the BOP drill column.   
     
     
         5 . The disaster mitigation system of  claim 1 , wherein the sealing annular ram comprises:
 (a) a surface to abut the surface of the housing;   (b) a threaded hole into which a guide pin is inserted;   (c) two recessed slots into which the locking mechanism engages, these slots having a wedge shape or other shape which matches the locking lugs of the locking mechanism;   (d) an outer diameter which inserts into the upper housing part inner diameter;   (e) a second, larger outer diameter which inserts into the second larger inner diameter of the upper housing part;   (f) this larger outer diameter surface having grooves in which to insert hydraulic seals which isolate well pressure from the hydraulic chamber;   (g) a step surface between the two diameters of (d) and (e) above, on which hydraulic pressure is applied for opening the annular ram;   (h) an inner diameter hole through, matching the diameter of the BOP drill column;   (i) a second, larger inner diameter which slides over the lower housing cap part;   (j) a flat surface on the end of the annular ram just above the sealing surface; and   (k) a flat surface between the two inner diameters which has equal surface area to the flat surface of item (j) above to prevent a force imbalance on the annular ram due to well pressures on unequal opposing surfaces.   
     
     
         6 . The disaster mitigation system of  claim 1 , wherein the locking mechanism of claim comprises two lugs, each inserted into the upper housing part through holes on sides opposite each other; each lug having wedge shape cam geometry or other geometry which matches the recessed slots in the annular ram to provide a tightening effect. 
     
     
         7 . The disaster mitigation system of  claim 1 , wherein the guiding mechanism comprises a guide pin inserted through a hole in the upper housing part, and threading into the annular ram, then sliding in the longitudinal slot of the upper housing part whereby the annular ram with its recessed slots maintain proper alignment with the locking lugs of  claim 6 . 
     
     
         8 . A method of mitigating blowout disaster when the Blowout Preventer (BOP) fails, this method comprising of pre-mounting a housing assembly in the BOP as a Drill-Through-Equipment (DTE) system, the housing assembly located in the BOP stack, below the EDS connecting flange, the housing assembly comprising of:
 (a) an upper housing part being equipped with an integrated blind shear ram;   (b) the lower housing cap part being equipped with an integrated casing shear or other chosen ram;   (c) a sliding annular ram within the housing configured to open and close side openings in the housing;   (d) a locking mechanism whereby the annular ram is locked into closed position;         
     
     
         9 . A method of mitigating blowout disaster in  claim 8  further comprising opening the housing's side openings in the housing assembly, whereby gaining access to and cutting the drill pipe, restoring function to the BOP. 
     
     
         10 . A method of mitigating blowout disaster in  claim 8 , further comprising diverting blowout through said side openings in housing. 
     
     
         11 . A method of mitigating blowout disaster in  claim 8 , further comprising closing the annular ram once BOP function is restored, whereby the spill is stopped. 
     
     
         12 . A method of mitigating blowout disaster in  claim 8 , further comprising locking the sliding annular ram into closed position with a locking mechanism. 
     
     
         13 . A system of mitigating blowout disasters when the BOP fails, comprising a means for pre-mounting a housing in the BOP as a Drill-Through-Equipment (DTE) system, the housing assembly comprising:
 (a) a housing means, equipped with integrated BOP blind shear ram, and a casing shear or other BOP ram of choice;   (b) a sealing means positioned inside the housing for opening and closing the housing;   (c) a means for locking the sealing means into closed position.   
     
     
         14 . A system of mitigating blowout disasters of  claim 13 , further comprising a means for sliding the sealing means in the housing to open side openings in the housing, whereby gaining access to the drill pipe. 
     
     
         15 . A system of mitigating blowout disasters of  claim 14 , further comprising a means for diverting total blowout through said side openings, whereby protecting the drill rig. 
     
     
         16 . A system of mitigating blowout disasters of  claim 14 , further comprising a means for remedying the failed BOP by said means for accessing said drill pipe through said side openings with cutting and/or forcing tools. 
     
     
         17 . A system of mitigating blowout disasters of  claim 14 , further comprising a means for closing the side openings in the housing, whereby stopping the spill.