Vertical subsea tree assembly control

Abstract

A vertical subsea tree is operated by a subsea control module supplied with hydraulic and electric power from the surface through the vertical subsea tree. A landing sub is communicatively coupled to the surface with a landing sub umbilical and run to the vertical subsea tree. The landing sub engages mating penetrations on an upper portion of the master valve block of the vertical subsea tree to supply flow passages extending from the penetrations to the subsea control module through the master valve block. The subsea control module is then operated through the landing sub umbilical to control operation of the vertical subsea tree.

What is claimed is: 
     
         1 . A method for controlling a subsea completion or workover assembly in a subsea well having a vertical subsea tree communicatively coupled with a subsea control module, the method comprising the steps of:
 (a) providing the vertical subsea tree with at least one master valve block passage leading from an inner portion of an upper mandrel of a master valve block to an exterior of the vertical subsea tree, wherein the at least one master valve block passage communicatively couples the vertical subsea tree with the subsea control module;   (b) providing the master valve block of the vertical subsea tree with at least one penetration on the inner portion of the upper mandrel communicatively coupled to the at least one master valve block passage;   (c) providing a landing sub having at least one landing sub passage extending from a landing sub penetration on a lower portion of the landing sub and connecting the at least one landing sub passage to an umbilical;   (d) running the landing sub and the umbilical from a floating platform to land the landing sub on the master valve block and registering the landing sub penetration with the master valve block penetration;   (e) supplying at least one of hydraulic fluid pressure and electric potential to the subsea control module through the umbilical, landing sub passage, and master valve block passage; and   (f) performing at least one of subsea completion operations and subsea workover operations with at least one of the hydraulic fluid pressure and the electrical potential, provided through the passages.   
     
     
         2 . The method of  claim 1 , wherein step (e) further comprises operating an isolation valve on the at least one master valve block passage to allow fluid flow through the at least one master valve block passage to the subsea control module. 
     
     
         3 . The method of  claim 1 , wherein:
 step (e) comprises supplying treatment fluids to the subsea control module through the umbilical, landing sub passage, and master valve block passage; and   step (f) comprises performing at least one of subsea completion operations and subsea workover operations with the treatment fluids provided through the passages.   
     
     
         4 . The method of  claim 1 , wherein the at least one master valve block passage and the at least one landing sub passage comprise a plurality of corresponding passages in communication through corresponding penetrations in the master valve block and the landing sub, step (e) comprising supplying hydraulic fluid pressure and electric potential to the subsea control module. 
     
     
         5 . The method of  claim 1 , wherein the landing sub comprises a subsea test tree and step (d) comprises running the subsea test tree through a riser extending from the vertical subsea tree to the platform, the umbilical running through the riser. 
     
     
         6 . The method of  claim 5 , wherein the subsea test tree is run through a blowout preventer interposed between the master valve block and the riser. 
     
     
         7 . The method of  claim 1 , wherein the landing sub is a lower riser package and step (d) comprises running the lower riser package and the umbilical through open water. 
     
     
         8 . The method of  claim 1 , wherein the landing sub is an emergency disconnect package and step (d) comprises running the emergency disconnect package and the umbilical through open water. 
     
     
         9 . The method of  claim 1 , wherein a remotely operated vehicle may communicate with the at least one passage through a hot stab plate located subsea and adjacent the subsea control module. 
     
     
         10 . The method of  claim 9 , wherein the at least one passage communicates with the subsea control module through the hot stab plate which is capped with a bridging plate having flow passages communicatively coupling the master valve block passages terminating at the hot stab plate with the flow passages extending between the hot stab plate and the subsea control module. 
     
     
         11 . A method for controlling a subsea completion or workover assembly in a subsea well having a vertical subsea tree communicatively coupled with a subsea control module, the method comprising the steps of:
 (a) providing the vertical subsea tree with a plurality master valve block passages leading from an inner portion of an upper mandrel of a master valve block to an exterior of the vertical subsea tree, wherein the plurality of passages communicatively couple the vertical subsea tree with the subsea control module;   (b) providing the master valve block of the vertical subsea tree with a plurality of penetrations on the inner portion of the upper mandrel, each communicatively coupled to a respective one of the plurality of master valve block passages;   (c) providing a landing sub having a plurality of landing sub passages extending from a plurality of corresponding landing sub penetrations on a lower portion of the landing sub and connecting the landing sub passages to an umbilical;   (d) running the landing sub and the umbilical from a floating platform to land the landing sub on the master valve block and registering the landing sub penetrations with the master valve block penetrations;   (e) supplying hydraulic fluid pressure, electric potential, and treatment fluids to the subsea control module through the umbilical, landing sub passages, and master valve block passages; and   (f) performing at least one of subsea completion operations and subsea workover operations with the hydraulic fluid pressure, the electrical potential, and the treatment fluids provided through the passages.   
     
     
         12 . The method of  claim 11 , wherein step (e) further comprises operating an isolation valve on each master valve block passage to allow fluid flow through the master valve block passages to the subsea control module. 
     
     
         13 . The method of  claim 11 , wherein step (e) comprises:
 supplying hydraulic fluid pressure through at least two of the landing sub passages and corresponding master valve block passages to the subsea control module; supplying electric potential through at least two of the landing sub passages and corresponding master valve block passages to the subsea control module; and   supplying treatment fluids through at least one of the landing sub passages and corresponding master valve block passages.   
     
     
         14 . The method of  claim 11 , wherein the landing sub comprises a subsea test tree and step (d) comprises running the subsea test tree through a riser extending from the vertical subsea tree to the platform, the umbilical running through the riser. 
     
     
         15 . The method of  claim 14 , wherein the subsea test tree is run through a blowout preventer interposed between the master valve block and the riser. 
     
     
         16 . The method of  claim 11 , wherein the landing sub is a lower riser package and step (d) comprises running the lower riser package and the umbilical through open water. 
     
     
         17 . The method of  claim 11 , wherein the landing sub is an emergency disconnect package and step (d) comprises running the emergency disconnect package and the umbilical through open water. 
     
     
         18 . The method of  claim 11 , wherein a remotely operated vehicle may communicate with the passages through a hot stab plate located subsea and adjacent to the subsea control module. 
     
     
         19 . The method of  claim 18 , wherein the passages communicate with the subsea control module through the hot stab plate which is capped with a bridging plate having flow passages communicatively coupling the master valve block passages terminating at the hot stab plate with the flow passages extending between the hot stab plate and the subsea control module. 
     
     
         20 . A subsea completion or workover assembly in a subsea well having a vertical subsea tree with a master valve block having an inner upper mandrel for receiving a landing sub, comprising:
 at least one master valve block passage leading from the inner portion of an upper mandrel of the master valve block to an exterior of the vertical subsea tree, the at least one master valve block passage further communicatively coupled to a subsea control module;   at least one penetration on the inner portion of the upper mandrel communicatively coupled to the at least one master valve block passage;   a landing sub having at least one landing sub passage extending from a landing sub penetration on a lower portion of the landing sub;   an umbilical connected to the landing sub, the at least one landing sub passage in communication with the umbilical;   wherein the landing sub lands on the master valve block and registers the landing sub penetration with the master valve block penetration; and   wherein at least one of hydraulic fluid pressure and electric potential are supplied to the subsea control module through the umbilical, landing sub passage, and master valve block passage to perform at least one of subsea completion and workover operations with at least one of the hydraulic fluid pressure and the electrical potential provided through the passages.   
     
     
         21 . The completion of  claim 20 , wherein treatment fluids are supplied to the subsea control module through the umbilical, landing sub passage, and master valve block passage to perform at least one of subsea completion and workover operations with the treatment fluids provided through the passages. 
     
     
         22 . The completion of  claim 20 , wherein an isolation valve is located on the at least one master valve block passage to allow fluid flow through the at least one master valve block passage to the subsea control module. 
     
     
         23 . The completion of  claim 20 , wherein the at least one master valve block passage and the at least one landing sub passage comprise a plurality of corresponding passages in communication through corresponding penetrations in the master valve block and the landing sub. 
     
     
         24 . The completion of  claim 20 , wherein:
 the landing sub comprises a subsea test tree;   a riser extends from the vertical subsea tree to the platform; and   the subsea test tree and umbilical are run through the riser.   
     
     
         25 . The completion of  claim 20 , wherein the landing sub is a lower riser package and the lower riser package and the umbilical are run through open water. 
     
     
         26 . The method of  claim 20 , wherein the landing sub is an emergency disconnect package and the emergency disconnect package and the umbilical are run through open water.