Single body choke line and kill line valves

Abstract

A well control system including a kill line and a choke line where the system is mounted on a wellhead, the choke line is connected to an annulus formed between an outer wall of drill pipe and an inner wall of casing, and the kill line is connected to the fluid in the drill pipe. The kill line includes a single valve body having first and second ends, and at least three cavities connected in series between the first and second ends. A first and second of the cavities includes a first and second gate valve, respectively, and a third of cavities includes a check valve. The choke line includes a single valve body having third and fourth ends, and a plurality of cavities connected in series between the third and fourth ends. A first and second of the cavities include a third and a fourth gate valve, respectively.

What is claimed is: 
     
         1 . A well control system comprising:
 a kill line; and   a choke line;   wherein the well control system is mounted on a wellhead,   wherein the choke line is connected to an annulus formed between an outer wall of drill pipe and an inner wall of casing,   wherein the kill line is connected to the fluid in the drill pipe,   wherein the kill line comprises:
 a single valve body having a first end, a second end, and at least three cavities connected in series between the first end and the second end;
 wherein a first of the at least three cavities comprises a first gate valve, a second of the at least three cavities comprises a second gate valve, and a third of the at least three cavities comprises a check valve, and 
 
   wherein the choke line comprises:
 a single valve body having a third end, a fourth end, and a plurality of cavities connected in series between the third end and the fourth end; 
 wherein a first of the plurality of cavities comprises a third gate valve, and a second of the plurality of cavities comprises a fourth gate valve. 
   
     
     
         2 . The well control system of  claim 1 , wherein the first gate valve is hydraulically actuated. 
     
     
         3 . The well control system of  claim 1 , wherein the second gate valve is manually actuated. 
     
     
         4 . The well control system of  claim 1  further comprising at least one blowout preventer,
 wherein the blowout preventer is distal from the wellhead. 
 
     
     
         5 . The well control system of  claim 1  wherein the first end of the kill line is connected to a spool. 
     
     
         6 . The well control system of  claim 1  wherein the third end of the choke line is connected to a spool. 
     
     
         7 . The well control system of  claim 1 , wherein the check valve is configured to prevent fluid flow out of the well. 
     
     
         8 . The well control system of  claim 1 , further comprising a temperature/pressure sensor,
 wherein the temperature/pressure sensor measures at least one member of the group consisting of temperature and pressure.   
     
     
         9 . A method of controlling release of fluids from below the wellhead, using a well control system, comprising at least one of closing a blowout preventer, closing at least one gate valve in a choke line, or introducing fluid into the well via a kill line,
 wherein the well control system comprises:
 a blowout preventer; 
 a kill line; and 
 a choke line; 
 wherein the well control system is mounted on a wellhead, 
 wherein the choke line is hydraulically connected to an annulus formed between an outer wall of drill pipe and an inner wall of casing, 
 wherein the kill line is hydraulically connected to the fluid in the drill pipe, 
 wherein the kill line comprises:
 a single valve body having a first end, a second end, and at least three cavities connected in series between the first end and the second end;
 wherein a first of the at least three cavities comprises a first gate valve, a second of the at least three cavities comprises a second gate valve, and a third of the at least three cavities comprises a check valve, and 
 
 
 wherein the choke line comprises:
 a single valve body having a third end, a fourth end, and a plurality of cavities connected in series between the third end and the fourth end; 
 wherein a first of the plurality of cavities comprises a third gate valve, and a second of the plurality of cavities comprises a fourth gate valve. 
 
   
     
     
         10 . The method of  claim 9 , wherein introducing fluid into the well via the kill line involves hydraulically actuating the first gate valve in the kill line. 
     
     
         11 . The method of  claim 9 , wherein introducing fluid into the well via the kill line involves manually actuating the second gate valve in the kill line. 
     
     
         12 . The method of  claim 10 , wherein the well control system further comprises a temperature/pressure sensor,
 wherein the temperature/pressure sensor measures at least one member of the group consisting of temperature and pressure.   
     
     
         13 . A kill line comprising a single valve body having a first end, a second end, and at least three cavities connected in series between the first end and the second end,
 wherein a first of the at least three cavities comprises a first gate valve, a second of the at least three cavities comprises a second gate valve, and a third of the at least three cavities comprises a check valve.   
     
     
         14 . The kill line of  claim 13 , wherein the first gate valve is hydraulically actuated. 
     
     
         15 . The kill line of  claim 13 , wherein the second gate valve is manually actuated. 
     
     
         16 . The kill line of  claim 13 , further comprising a temperature/pressure sensor,
 wherein the temperature/pressure sensor measures at least one member of the group consisting of temperature and pressure.