High-integrity pressure protection system Christmas tree

1. An apparatus comprising:

a Christmas tree;

a choke coupled to receive fluid from the Christmas tree; and

a high-integrity pressure protection system including pressure sensors downstream of the choke, valves upstream of the choke, and a logic solver connected to control operation of the valves of the high-integrity pressure protection system that are upstream of the choke, wherein the valves of the high-integrity pressure protection system that are upstream of the choke include at least two valves of the Christmas tree.

2. The apparatus of claim 1 , wherein the at least two valves of the Christmas tree and of the high-integrity pressure protection system include a wing valve of the Christmas tree and a master valve of the Christmas tree.

3. The apparatus of claim 1 , wherein the pressure sensors of the high-integrity pressure protection system include three pressure sensors.

4. The apparatus of claim 3 , wherein the logic solver is configured to command one or more of the valves of the at least two valves of the Christmas tree to close in response to at least two of the three pressure sensors detecting pressure downstream of the choke above a threshold level.

5. The apparatus of claim 1 , wherein the logic solver includes an electronic logic device and the pressure sensors include pressure transducers.

6. The apparatus of claim 1 , wherein the logic solver includes a hydraulic logic solver.

7. The apparatus of claim 1 , wherein the Christmas tree is a surface Christmas tree.

8. An apparatus comprising:

a distributed high-integrity pressure protection system including:

a plurality of pressure sensors of the distributed high-integrity pressure protection system, wherein the plurality of pressure sensors is connected to measure pressure downstream of a choke; and

a plurality of valves of the distributed high-integrity pressure protection system, wherein the plurality of valves is connected to control flow upstream of the choke; and

a controller of the distributed high-integrity pressure protection system, wherein the controller is configured to control operation of the plurality of valves upstream of the choke based on the pressure measured by the plurality of pressure sensors downstream of the choke.

9. The apparatus of claim 8 , wherein the plurality of valves of the distributed high-integrity pressure protection system includes one or more valves of a Christmas tree.

10. The apparatus of claim 8 , wherein each valve of the plurality of valves of the distributed high-integrity pressure protection system is a valve of a Christmas tree.

11. The apparatus of claim 8 , wherein each valve of the plurality of valves of the distributed high-integrity pressure protection system is a valve of a subsea Christmas tree.

12. The apparatus of claim 8 , comprising the choke.

13. The apparatus of claim 8 , wherein the controller is an electronic logic device.

14. A method comprising:

coupling pressure sensors of a high-integrity pressure protection system to a fluid conduit downstream of a Christmas tree so as to allow monitoring of fluid conduit pressure downstream of the Christmas tree with the pressure sensors of the high-integrity pressure protection system;

coupling a logic solver of the high-integrity pressure protection system to the pressure sensors of the high-integrity pressure protection system; and

incorporating valves of the Christmas tree as part of the high-integrity pressure protection system by coupling the valves to the logic solver of the high-integrity pressure protection system so as to allow the logic solver of the high-integrity pressure protection system to control operation of the valves based on the monitored fluid conduit pressure downstream of the Christmas tree.

15. The method of claim 14 , comprising routing a produced fluid through the high-integrity pressure protection system.

16. The method of claim 15 , comprising monitoring the fluid conduit pressure downstream of the Christmas tree with the pressure sensors of the high-integrity pressure protection system.

17. The method of claim 16 , comprising:

detecting that the monitored fluid conduit pressure downstream of the Christmas tree has exceeded a threshold level; and

automatically closing one or more of the valves of the Christmas tree in response to detecting that the monitored fluid conduit pressure downstream of the Christmas tree has exceeded the threshold level.

18. The method of claim 15 , comprising routing the produced fluid through a choke positioned downstream of the valves of the Christmas tree incorporated as part of the high-integrity pressure protection system and positioned upstream of the pressure sensors of the high-integrity pressure protection system.