CHOKE SYSTEM FOR WELLHEAD ASSEMBLY HAVING A TURBINE GENERATOR

• US 20180100374A1
• Filed: 10/06/2016
• Published: 04/12/2018
• Est. Priority Date: 10/06/2016
• Status: Active Grant

• Current Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Original Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Inventors: Al-Dossary, Faisal M., Al-Zahrani, Mohammed S.
• Granted Patent: US 10,458,206 B2
• Time in Patent Office: Days
• CPC Class Codes: E21B 33/03 Well heads; Setting-up thereof
• CPC Class Codes: E21B 34/025 Chokes or valves in wellheads and sub-sea wellheads for variably regulating fluid flow
• CPC Class Codes: E21B 41/0085 Adaptations of electric power generating means for use in boreholes
• CPC Class Codes: E21B 43/12 Methods or apparatus for controlling the flow of the obtained fluid to or in wells E21B43/25 takes precedence; valve arrangements E21B34/00
• CPC Class Codes: E21B 47/06 Measuring temperature or pressure
• CPC Class Codes: F01D 21/006 Arrangements of brakes brakes per se F16D
• CPC Class Codes: F05B 2220/602 with energy recovery turbines
• CPC Class Codes: H02P 3/04 Means for stopping or slowing by a separate brake, e.g. friction brake or eddy-current brake

Abstract

A wellhead assembly for use with a well that includes a production tree, a production line for carrying produced fluid from the production tree, and a choke in the production line. The choke assembly includes a turbine member that rotates in response to fluid flowing through the production line. The kinetic energy of the rotating turbine is converted into electricity by a generator that is coupled with the turbine member. Selectively impeding turbine rotation with a brake system introduces a pressure drop in the production line fluid, and which regulates flow of the production line fluid. The turbine member can be disposed in a straight run of the production line, or adjacent a bend in the production line.

Claims

1. A wellhead assembly for producing fluid from a wellbore comprising:

a production tree;

production piping connected to the production tree; and

a choke assembly comprising,

a housing having a chamber that is in fluid communication with the production piping,

a braking system, and

a turbine element in the housing that rotates in response to a flow of fluid from the production piping through the housing, that is changeable between a freely rotating configuration to a rotationally impeded configuration when in braking engagement with the braking system, so that a pressure drop across the turbine element in the flow of fluid regulates the flow of fluid in the production piping.

2. The wellhead assembly of claim 1, further comprising a generator coupled with the turbine element.

3. The wellhead assembly of claim 2, further comprising an electrical load in electrical communication with the generator.

4. The wellhead assembly of claim 3, wherein the electrical load comprises a device selected from group consisting of a light, a gauge, a detector, and a flowmeter.

5. The wellhead assembly of claim 1, wherein a shaft couples the turbine element with the braking system.

6. The wellhead assembly of claim 5, wherein the braking system comprises a braking device selected from the group consisting of calipers that are in selective retarding contact with the shaft, and a magnet that strategically forms a magnetic field to selectively impede rotation of the shaft and the turbine element.

7. The wellhead assembly of claim 1, wherein the braking system is responsive to pressure in the production piping.

8. The wellhead assembly of claim 7, further comprising a pressure sensor in pressure communication with the production piping at a location downstream of the choke assembly, and which is in signal communication with the braking system.

9. The wellhead assembly of claim 1, wherein the turbine member comprises a hub that is generally coaxial with the production piping and turbine elements that project radially outward from the hub.

10. The wellhead assembly of claim 1, wherein the turbine member comprises spaced apart hubs that are each arranged generally perpendicular with an axis of the production piping, and turbine elements that each span between the hubs and along helical paths.

11. A method of producing fluid from a wellbore comprising:

directing fluid produced from the wellbore through production piping that is attached to a production tree and across a turbine member that is rotatable in response to fluid flow;

monitoring conditions in the production piping; and

regulating fluid flow through the production piping by selectively impeding rotation of the turbine member in response to conditions monitored in the production piping.

12. The method of claim 11, wherein impeding rotation of the turbine member increases a pressure drop in fluid flowing past the turbine member.

13. The method of claim 11, further comprising converting kinetic energy in the rotating turbine member to electricity, and powering devices adjacent an opening of the wellbore with the electricity.

14. The method of claim 11, wherein the conditions monitored in the production piping comprise fluid pressure which is measured downstream of the turbine member.

15. A choke assembly for regulating flow from a wellbore comprising:

a housing having a chamber that receives a flow of fluid from the wellbore; and

a turbine member in the chamber that rotates in response to the flow of fluid in the chamber, and that selectively resists rotation in response to conditions of the flow of fluid to regulate the flow of fluid flowing through the chamber.

16. The choke assembly of claim 15, further comprising a generator coupled with the turbine member and that generates electricity in response to rotation of the turbine member.

17. The choke assembly of claim 15, wherein rotation of the turbine member is selectively resisted by a brake system that is coupled with the turbine member.

18. The choke assembly of claim 17, further comprising a pressure sensor in production piping downstream of the chamber and that is in communication with the brake system.

19. The choke assembly of claim 15, further comprising a generator and a brake system that are coupled to a shaft, wherein the shaft is in an orientation that is coaxial with the production piping and perpendicular to the production piping.

20. The choke assembly of claim 15, further comprising a generator and a brake system coupled with the turbine member, and wherein electricity is generated by the generator which is used to power the brake system to impede rotation of the turbine member.