Ball seat for use in a wellbore
A downhole device shifts a component from a first state to a second state. The device includes a body having the component in a bore thereof and an annular space formed within an inner and outer wall of the body. The annular space includes a first fluid chamber in fluid communication with the bore at a first location and with a pressure transducer at a second location, the transducer constructed and arranged to measure pressure of the fluid and provide a signal to circuitry controlling a valve upon reception of a predetermined fluid pressure pulse sequence. When the pulse sequence is delivered, the valve opens, placing a source of pressurized fluid in communication with an actuator that shifts the valve.
1. A ball seat apparatus, comprising:
a body, the body for installation in a string of wellbore tubulars, the body having a bore therethrough;
a ball seat disposed in the bore, the seat having a smaller and a larger inner diameter positions, wherein in the smaller inner diameter position the seat is constructed and arranged to retain a ball of a predetermined diameter in a manner whereby the bore of the body is substantially sealed;
an annular area formed in a wall of the body, the annular area including:
a wellbore fluid chamber, the chamber in fluid pressure communication with the bore of the apparatus;
fluid communication between the wellbore fluid chamber and a tubing pressure transducer, the tubing pressure transducer for measuring tubing pressure;
communication between the tubing pressure transducer and a valve assembly, the assembly including a valve, the valve openable upon a predetermined set of pressure values received by the transducer; and
selective fluid communication between the valve and an actuator, the actuator including an annular piston constructed and arranged to move the ball seat from the smaller inner diameter to the larger inner diameter position.
2. The apparatus of claim 1 , wherein the values include at least two distinct fluid pressure pulses.
3. The apparatus of claim 2 , wherein the values further include at least one predetermined time delay between the fluid pressure pulses.
4. The apparatus of claim 2 , wherein the values include at least one predetermined time delay after the last pulse in a sequence of fluid pressure pulses.
5. The apparatus of claim 1 , further including a hydraulic fluid chamber in pressure communication with the wellbore fluid chamber, the chambers separated by a floating piston.
6. The apparatus of claim 1 , wherein the ball seat includes a plurality of castellations connected at a first end to a sealing ring, the sealing ring providing a sealing relationship between the ball seat and the bore and between the ball and the ball seat.
7. The apparatus of claim 6 , wherein as the ball seat is moved from the smaller inner diameter to the larger inner diameter position, an inner diameter of the sealing ring is expanded.
8. The apparatus of claim 1 , further including an annulus pressure transducer for operation in conjunction with the tubing pressure transducer to provide an effective pressure.
9. The apparatus of claim 1 , wherein the valve assembly further includes a Kevlar fuse for operating the valve upon receipt of the predetermined set of values.
10. The apparatus of claim 1 , wherein fluid communication within the apparatus is provided by a first, second, third, and fourth fluid paths.
11. A downhole device for shifting a component from a first state to a second state, comprising:
a body, the body having the component in a bore thereof and an annular space formed within an inner and outer walls of the body, the annular space including:
a first fluid chamber, the chamber in fluid communication with the bore at a first location and with a pressure transducer at a second location, the transducer constructed and arranged to measure pressure of the fluid and provide a signal to circuitry controlling a valve upon reception of a predetermined fluid pressure pulse sequence, the pulses generated at a surface of a wellbore;
wherein, when the pressure pulse sequence is delivered, the valve opens, placing a source of pressurized fluid in communication with an actuator that shifts the component from the first to the second state.
12. The device of claim 11 , wherein the actuator is an annular piston disposed in the annular area.
13. The device of claim 12 , wherein the component is a ball seat and the second state is an open state wherein a passage through the ball seat is enlarged from the first state.
14. A method of setting a pressure actuated tool in a wellbore, comprising:
providing the pressure actuated tool in a string of tubulars;
providing an apparatus in the tubular string below the pressure actuated tool, the apparatus including a ball seat;
dropping a ball into the ball seat, thereby sealing a bore through the apparatus;
increasing pressure in the string above the apparatus;
setting the pressure actuated tool;
providing a predetermined sequence of fluid pressure pulses to the apparatus;
providing a tubing pressure transducer in the apparatus in fluid contact with the fluid pressure pulse sequence;
providing a valve assembly including circuitry in the apparatus whereby the circuitry, upon receipt of the fluid pressure pulse sequence by the transducer, causes a valve in the valve assembly to open and pressurized fluid to pass therethrough;
providing a piston in the apparatus having a piston surface formed thereon for shifting the ball seat from a first smaller diameter position to a second larger diameter position;
placing the piston surface in contact with the pressurized fluid from the open valve;
shifting the ball seat to the second larger diameter position, whereby the ball is released, thereby reopening the bore.
15. The method of claim 14 , wherein the pressure actuated tool is a packer.
16. The method of claim 15 , wherein the predetermined sequence of fluid pressure pulses is more than two.
17. The method of claim 16 , wherein the sequence of fluid pressure pulses includes a predetermined time delay between at least two of the pulses.