Electric surface controlled subsurface valve system

• US 4,981,173 A
• Filed: 06/14/1989
• Issued: 01/01/1991
• Est. Priority Date: 03/18/1988
• Status: Expired due to Term

• Current Assignee: Halliburton Company
• Original Assignee: Otis Engineering Corporation (Halliburton Company)
• Inventors: Perkins, Donald H., Deaton, Thomas M.
• Primary Examiner(s): Neuder, William P.
• Application Number:
  US07/365,701
• Time in Patent Office: 566 Days
• Field of Search: 166/246, 166/65.1, 166/66.4, 166/66.5, 166/332, 439/193, 251/129.04, 251/129.09, 251/129.15, 251/129.18, 137/418, 137/521
• US Class Current: 166/66.7
• CPC Class Codes: E21B 2200/05 Flapper valves
• CPC Class Codes: E21B 34/066 electrically actuated

Abstract

A solenoid operated valve system for petroleum production wells including a solenoid operated valve securable in a well bore connected to the lower end of a tubing string extending to the surface. The valve of the system includes an outer housing, an inner wall defining a flow passageawy therethrough and an annular cavity therebetween for receiving the solenoid coil and associated electrical components. The spaces in the annular cavity surrounding the solenoid coil and components is filled with an electrically insulative filler material to protect the electrical elements from borehole fluids. The solenoid operated valve has an operator tube formed of tubular sections of different magnetic characteristics so that the valve is opened against a biasing spring by a high current flow and held open by a current flow of a lower value. The valve solenoid is operable by either AC or DC current.

Claims

1. An electrically operated solenoid actuated safety valve system for use in a borehole, comprising:

an elongate tubular safety valve housing assembly having one end adapted for attachment to the lower end of a tubing string within the borehole, and the other end adapted to control the entry of borehole fluids into the assembly, said housing assembly including an outer housing, an inner wall defining a tubular passageway for allowing fluid flow through the valve assembly, and an annular space therebetween;

a tubular magnetic armature member having a lower end adapted for engaging a valve closure member to effect opening of the valve, said member being mounted for axial movement within the tubular passageway through said housing assembly from a spring biased upper retracted position disengaged from said closure member and closing said valve to a lower extended position engaged with said closure member and opening said valve;

a tubular electrical solenoid coil positioned in the annular space between the outer housing and the inner wall of said housing assembly and, at an axial location below the upper retracted position of said magnetic armature, the opposite ends of the wire coil comprising said solenoid extending through the annular space toward the end of the housing assembly adapted to be connected to the tubing;

means for connecting said wire ends to an electrical cable extending from the surface of the borehole to enable current to flow through the solenoid coil and cause movement of the tubular armature member of said valve toward its lower extended position and effect opening of the valve; and

an electrically insulative filler material filling the annular space in substantially all regions thereof not occupied by said solenoid coil and wires to prevent the entry of borehole fluids into said annular space.

2. An electrically operated solenoid actuated safety valve system as set forth in claim 1, wherein said electrically insulative filler material comprises an epoxy resin.

3. An electrically operated solenoid actuated valve safety system as set forth in claim 1 which also includes means for applying a first higher value of current to the electrical cable extending from the surface to the solenoid coil to effect downward movement of the tubular magnetic armature member and a second lower value of current to the solenoid coil to hold the armature in its lower position with the valve open once actuation has been effected.

4. An electrically operated solenoid actuated valve safety system as set forth in claim 1 wherein said tubular magnetic armature member includes an elongate operator tube having a cylindrical armature portion formed of highly magnetic material and the safety valve housing assembly also includes a magnetic stop located near the lower end of the armature portion when the operator tube is in its lower position to effect the allowance of holding of the armature in the lower position at a lower value of current through the solenoid coil.

5. An electrically operated solenoid actuated safety valve system as set forth in claim 1, which also includes a programmable current source connected to the electrical cable extending from the surface to the solenoid coil for supplying preselected values of electric current to said solenoid coil.

6. An electrically operated solenoid actuated safety valve system as set forth in claim 5, wherein said elongate operator tube comprises:

an upper cylindrical tube section having relatively thin walls and being formed of relatively less magnetic material;

a lower cylindrical tube section having relatively thin walls and being formed of relatively less magnetic material; and

a central cylindrical tubular armature portion coaxially connected between said upper and said lower sections and being formed of highly magnetic material, said armature portion being located near the upper end of said solenoid coil for downward movement in response to current flow through said solenoid.

7. An electrically operated solenoid actuated safety valve system as set forth in claim 6 which also includes:

a helical spring surrounding said operator tube for spring biasing said tube toward its upper position;

8. An electrically operated solenoid actuated safety valve system as set forth in claim 7 which also includes:

a cylindrical magnetic stop formed of highly magnetic material mounted to the lower end of said coil tube adjacent the lower end of said solenoid coil surrounding the lower cylindrical section of said operator tube and having upper edges being spaced by an air from the lower edges of the armature portion of the operator tube when said tube is located in its lower position in response to current flow through said coil, said magnetic stop serving to retain said operator tube in its lower position by means of a lower value of current flow through the coil than that required to initially move the tube from its upper to its lower position against its spring bias.

9. An electrically operated solenoid actuated safety valve system as set forth in claim 7 wherein said operator tube also includes a lowest cylindrical tube section having relatively thin walls and being formed of relatively less magnetic material and coaxially connected to the end of said lower section by a radially extending junction flange which abuts the upper end of said helical spring for upwardly biasing said operator tube.

10. An electrically operated solenoid actuated safety valve system as set forth in claim 1 wherein said electrically insulative filler material also protects the components it surrounds from borehole pressures.

11. An electrically operated solenoid actuated safety valve system as set forth in claim 11 wherein the filler material is a high tear strength silicone elastomer.

12. An electrically operated solenoid actuated safety valve system for use in a borehole, comprising:

an elongate tubular safety valve housing assembly having one end adapted for attachment to the lower end of a tubing string within the borehole, and the other end adapted to control the entry of borehole fluids into the assembly, said housing assembly including an outer housing, an inner wall defining a tubular passageway for allowing fluid flow through the valve assembly, and an annular space therebetween;

a tubular magnetic armature mounted for axial movement within the tubular passageway through said housing assembly from a spring biased upper retracted position closing said valve to a lower extended position opening said valve;

a tubular electrical solenoid soil positioned in the annular space between the outer housing and the inner wall of said housing assembly and at an axial location below the upper retracted position of said armature, the opposite ends of the wire coil comprising said solenoid extending through the annular space toward the end of the housing assembly adapted to be connected to the tubing, said solenoid coil being wound upon a cylindrical coil tube the inside surface of which comprises a portion of the inner wall defining the tubular passageway through the elongate housing assembly, said coil tube being formed of non-magnetic material having relatively thin walls to increase the degree of magnetic coupling between the solenoid coil and the tubular magnetic armature;

means for connecting said wire ends to an electrical cable extending from the surface of the borehole to enable current to flow through the solenoid coil and cause movement of the tubular armature of said valve toward its lower extended position and effect opening of the valve; and

an electrically insulative filler material filling the annular space in substantially all regions thereof not occupied by said solenoid coil and wires to prevent the entry of borehole fluids into said annular space.

13. An electrically operated solenoid actuated safety valve system as set forth in claim 12 wherein said elongate housing assembly also includes a cylindrical anti-rotation adjustment tube threadedly coupled to the upper end of said coil tube for adjustment of the length thereof in the longitudinal direction to secure a snug fit within a recess in the inner wall of the outer housing.

14. An electrically operated solenoid actuated safety valve system for use in a borehole, comprising:

an elongate tubular safety valve housing assembly having one end adapted for attachment to the lower end of a tubing string within the borehole, and the other end adapted to control the entry of borehole fluids into the assembly, said housing assembly including an outer housing, an inner wall defining a tubular passageway for allowing fluid flow through the valve assembly, and an annular space therebetween, said elongate housing assembly also including;

a cylindrical outer housing having relatively thick walls for resisting borehole pressures and forces;

a cylindrical coil tube having relatively thin walls and an outer diameter less than the inner diameter of the outer housing to form said annular space therebetween, the inner walls of said coil tube receiving said elongate operator tube for coaxial movement therein;

a tubular magnetic armature mounted for axial movement within the tubular passageway through said housing assembly from a spring biased upper retracted position closing said valve to a lower extended position opening said valve;

a tubular electrical solenoid coil positioned in the annular space between the outer housing and the inner wall of said housing assembly and, at an axial location below the upper retracted position of said armature, the opposite ends of the wire coil comprising said solenoid extending through the annular space toward the end of the housing assembly adapted to be connected to the tubing, said solenoid coil being wound upon the outer surface of said coil tube;

means for connecting said wire ends to an electrical cable extending from the surface of the borehole to enable current to flow through the solenoid coil and cause movement of the tubular armature of said valve toward its lower extended position and effect opening of the valve; and

an electrically insulative filler material filling the annular space in substantially all regions thereof not occupied by said solenoid coil and wires to prevent the entry of borehole fluids into said annular space.

15. A solenoid operated safety valve for use in a petroleum production well having fluid production tubing extending down a borehole, wherein said solenoid actuated valve includes:

an elongate housing assembly having a central passageway therethrough and an annular cavity located between the outside wall of said housing and the inside wall defining the passageway;

means for connecting the upper end of said housing to the lower end of the tubing for fluid communication between the tubing and the passageway;

a normally closed valve flapper mounted to the lower end of said elongate housing and extending across the lower end of the passageway to prevent the flow of fluids from within the borehole into the passageway;

a solenoid energization coil mounted within the annular cavity located in the sidewalls of said elongate housing and surrounding the passageway;

an elongate operator tube formed of magnetic material coaxially mounted for limited longitudinal movement in the downward direction within the passageway through said housing in response to magnetic forces produced by said solenoid coil, said operator tube having an longitudinal opening to permit the flow of fluids therethrough and having the lower end thereof positioned adjacent the normally closed valve flapper to open said valve upon downward movement of said operator tube;

means for electrically connecting the ends of the wire coil forming said solenoid energization coil to a source of electrical potential to complete the electrical circuit for energizing said solenoid coil and moving said operator tube in the downward direction to open the valve; and

an electrically insulative filler material surrounding said solenoid coil and filling the open space within the annular cavity located in the sidewalls of said housing to insulate the electrical components of said solenoid coil from borehole fluids.

16. A solenoid operated safety valve as set forth in claim 15, wherein said electrically insulative filler material comprises an epoxy resin.

17. A solenoid operated safety valve as set forth in claim 15 which also includes means for applying a first higher value of current to the electrical coil to effect downward movement of said operator tue and a second lower value of current to the solenoid coil to hold said operator tube in its lower position with the flapper valve open once actuation has been effected.

18. A solenoid operated safety valve as set forth in claim 15 wherein said elongate operator tube includes a cylindrical armature portion formed of highly magnetic material and said housing assembly also includes a magnetic stop located near the lower end of the armature portion when the operator tube is in its lower position to effect the allowance of holding of the armature in the lower position at a lower value of current through the solenoid coil.

19. A solenoid operated safety valve as set forth in claim 15, which also includes a programmable current source for supplying preselected values of electric current to said solenoid coil.

20. A solenoid operated safety valve as set forth in claim 18, wherein said elongate operator tube comprises:

an upper cylindrical tube section having relatively thin walls and being formed of relatively less magnetic material;

a lower cylindrical tube section having relatively thin walls and being formed of relatively less magnetic material; and

a central cylindrical tubular armature portion coaxially connected between said upper and said lower sections and being formed of highly magnetic material, said armature portion being located near the upper end of said solenoid coil for downward movement in response to current flow through said solenoid.

21. A solenoid operated safety valve as set forth in claim 20 which also includes:

a helical spring surrounding said operator tube for spring biasing said tube toward its upper position.

22. An electrical solenoid actuated safety system as set forth in claim 21 which also includes:

a cylindrical magnetic stop formed of highly magnetic material mounted to the lower end of said coil tube adjacent the lower end of said solenoid coil surrounding the lower cylindrical section of said operator tube and having upper edges being spaced by an air gap from the lower edges of the armature portion of the operator tube when said tube is located in its lower position in response to current flow through said coil, said magnetic stop serving to retain said operator tube in its lower position by means of a lower value of current flow through the coil than that required to initially move the tube from its upper to its lower position against its spring bias.

23. A solenoid operated safety valve as set forth in claim 21 wherein said operator tube also includes a lowest cylindrical tube section having relatively thin walls and being formed of relatively less magnetic material and coaxially connected to the end of said lower section by a radially extending junction flange which abuts the upper end of said helical spring for upwardly biasing said operator tube.

24. A solenoid operated safety valve as set forth in claim 15 wherein said electrically insulative filler material also protects the components it surrounds from borehole pressures.

25. A solenoid operated safety valve as set forth in claim 24 wherein the filler material is a high tear strength silicone elastomer.

26. A solenoid operated safety valve for use in a petroleum production well having fluid production tubing extending down a borehole, wherein the solenoid actuated valve includes:

an elongate housing assembly having a central passageway therethrough and an annular cavity located between the outside wall of said housing and the inside wall defining the passageway;

means for connecting the upper end of said housing to the lower end of the tubing for fluid communication between the tubing and the passageway;

a normally closed valve flapper mounted to the lower end of said elongate housing and extending across the lower end of the passageway to prevent the flow to fluids for within the borehole into the passageway;

a solenoid energization coil mounted within the annular cavity located in the sidewalls of said elongate housing and surrounding the passageway, said solenoid energization coil being wound upon a cylindrical coil tube the inside surface of which comprises a portion of the inner wall defining the tubular passageway through the elongate housing assembly, said coil tube being formed of non-magnetic material having relatively thin walls to increase the degree of magnetic coupling between the solenoid coil and the tubular magnetic armature;

an elongate operator tube formed of magnetic material coaxially mounted for limited longitudinal movement in the downward direction within the passageway through said housing in responses to magnetic forces produced by said solenoid coil, said operator tube having an longitudinal opening to permit the flow of fluids therethrough and having the lower end thereof positioned adjacent the normally closed valve flapper to open said valve upon downward movement of the said operator tube;

means for electrically connecting the ends of the wire coil forming said solenoid energization coil to a source of electrical potential to complete the electrical circuit for energizing said solenoid coil and moving said operator tube in the downward direction to open the valve; and

an electrically insulative filler material surrounding said solenoid coil and filling the open space within the annular cavity located in the sidewalls of said housing to insulate the electrical components of said solenoid coil from borehole fluids.

27. A solenoid operated safety valve as set forth in claim 26 wherein said elongate housing assembly also includes a cylindrical anti-rotation adjustment tube threadedly coupled to the upper end of said coil tube for adjustment of the length thereof in the longitudinal direction to secure a snug fit within a recess in the inner wall of the outer housing.

28. A solenoid operated safety valve for use in a petroleum production well having fluid production tubing extending down a borehole, wherein the solenoid actuated valve includes an elongate housing assembly having a central passageway therethrough and an annular cavity located between the outside wall of said housing and the inside wall defining the passageway;

said elongate housing assembly including;

a cylindrical outer housing having relatively thick walls for resisting borehole pressures and forces;

a cylindrical coil tube having relatively thin walls and an outer diameter less than the inner diameter of the outer housing to form said annular space therebetween, the inner walls of said coil tube receiving said elongate operator tube for coaxial movement therein;

means for connecting the upper end of said housing to the lower end of the tubing for fluid communicating between the tubing and the passageway;

a normally closed valve flapper mounted to the lower end of said elongate housing and extending across the lower end of the passageway to prevent the flow of fluids from within the borehole into the passageway;

a solenoid energization coil mounted within the annular cavity located in the sidewalls of said elongate housing and surrounding the passageway, said solenoid energization coil being wound upon the outer surface of said coil tube;

an elongate operator tube formed of magnetic material coaxially mounted for limited longitudinal movement in the downward direction within the passageway through said housing in response to magnetic forces produced by said solenoid coil, said operator tube having an longitudinal opening to permit the flow of fluids therethrough and having the lower end thereof positioned adjacent the normally closed valve flapper to open said valve upon downward movement of said operator tube;

means for electrically connecting the ends of the wire coil forming said solenoid energization coil to a source of electrical potential to complete the electrical circuit for energizing said solenoid coil and moving said operator tube in the downward direction to open the valve; and

an electrically insulative filler material surrounding said solenoid coil and filling the open space within the annular cavity located in the sidewalls of said housing to insulate the electrical components of said solenoid coil from borehole fluids.