Degradable material time delay system and method

Patent metadata

Field	Value
Publication number	US-10208570-B2
Application number	US-201615220042-A
Country	US
Kind code	B2
Filing date	Jul 26, 2016
Priority date	Feb 25, 2016
Publication date	Feb 19, 2019
Grant date	Feb 19, 2019

Abstract

A time delay tool and method in a wellbore casing is disclosed. The tool/method includes a mechanical restraining element, a reservoir for containing a reactive fluid, an actuating device and a wellbore device. When a stored energy is applied on the wellbore device, the actuation device is actuated and enables the reactive fluid in the reservoir to come in contact with the mechanical restraining element. While the mechanical restraining element undergoes a change in shape due to a chemical reaction, a stored energy applied on the wellbore device is delayed by a pre-determined time delay. The amount of the pre-determined time delay is determined by factors that include the reactive fluids, concentration of the reactive fluids, geometry and size of the mechanical restraining element.

First claim

What is claimed is:

1. A time delay method using a wellbore time delay tool, the method comprising the steps of:
positioning the wellbore time delay tool in a wellbore, wherein a body of the wellbore time delay tool defines an internal chamber that extends along the wellbore time delay tool, a first end of the internal chamber is closed by a first actuator device and a second end is closed by a second actuator device, and the internal chamber is in fluid communication (1) with a pressure port at the first end, when the first actuator device is actuated, and (2) with an energetic device at the second end, when the second actuator device is actuated;
actuating the second actuator device thereby causing a flow of a reactive fluid, which is housed in the internal chamber, in the wellbore time delay tool, from a first side of the second actuator device to a second side of the second actuator device;
initiating a chemical reaction between a mechanical restraining element on the second side of the second actuator device and the reactive fluid, the mechanical restraining element being located around one end of a wellbore device and restraining the wellbore device;
changing a physical property of the mechanical restraining element by the chemical reaction; and
releasing the wellbore device due to the changed physical property of the mechanical restraining element,
whereby an elapsed time between the step of actuating and the step of releasing the wellbore device comprises a time delay of the wellbore time delay tool.

2. The time delay method of claim 1 wherein each of the first and second actuator device ruptures when a pressure at the pressure port is higher then a threshold pressure.

3. The time delay method of claim 1 wherein the mechanical restraining device is a nut.

4. The time delay method of claim 1 wherein the step of releasing includes releasing a firing pin of a perforating charge.

5. The time delay method of claim 1 wherein the step of actuating the second actuator device includes bursting a rupture disk.

6. The time delay method of claim 1 wherein the step of actuating the second actuator device includes using an electronic switch.

7. The time delay method of claim 1 wherein the step of actuating the second actuator device includes using a magnetic field.

8. The time delay method of claim 1 wherein the step of actuating the second actuator device includes applying stored energy of a spring.

9. The time delay method of claim 1 wherein the step of actuating the second actuator device includes applying stored energy of a weight.

10. The time delay method of claim 1 wherein the step of releasing includes causing a piston to move.

11. The time delay firing method of claim 1 wherein the step of releasing includes opening the pressure port.

12. The time delay firing method of claim 1 wherein the step of releasing includes unplugging the wellbore device.

13. The time delay firing method of claim 1 wherein the step of releasing includes enabling rotational motion in the wellbore device.

14. The time delay firing method of claim 1 wherein the step of releasing includes opening a port in the wellbore device.

15. The time delay firing method of claim 1 wherein the elapsed time ranges from 2 days to 14 days.

16. The time delay firing method of claim 1 wherein the elapsed time ranges from 1 hour to 48 hours.

17. The time delay firing method of claim 1 wherein the elapsed time ranges from 0.01 seconds to 1 hour.

18. The method of claim 1 wherein the elapsed time ranges from 0.01 hours to 1 hour.

19. A method of causing a time delayed activity using a wellbore time delay tool, the method comprising the steps of:
positioning the wellbore time delay tool in a wellbore, wherein a body of the wellbore time delay tool defines an internal chamber that extends along the wellbore time delay tool, a first end of the internal chamber is closed by an actuator device, and a second end is closed by a bursting disk, and the internal chamber is in fluid communication (1) with a pressure port at the first end, when the actuator device is actuated and (2) with an energetic device at the second end, when the bursting disk is actuated;
rupturing the bursting disk in the wellbore time delay tool thereby causing a flow of a reactive fluid, contained in the internal chamber of the wellbore time delay tool, from a first side of the bursting disk to a second side of the bursting disk;
initiating a chemical reaction between a mechanical restraining element on the second side of the bursting disk and the reactive fluid to change a physical property of the mechanical restraining element, the mechanical restraining element being located around one end of a firing pin of a wellbore device and restraining the wellbore device;
changing a physical property of the mechanical restraining element by the chemical reaction; and
releasing the firing pin of the wellbore device due to the changed physical property of the mechanical restraining element;
whereby an elapsed time between the step of actuating and the step of releasing the wellbore device comprises a time delay of the wellbore time delay tool.

20. The method of claim 19 wherein the elapsed time ranges from 1 hour to 48 hours.

Assignees

• Geodynamics Inc

Inventors

• Hardesty John T
• Roessler Dennis
• George Kevin R

Classifications

• E21B43/1185 Primary

  Ignition systems · CPC title

• E21B34/063

  Valve or closure with destructible element, e.g. frangible disc (E21B34/103 takes precedence) · CPC title

• E21B43/11852

  hydraulically actuated · CPC title

• E21B33/12

  Packers; Plugs (used for cementing E21B33/134, E21B33/16) · CPC title

• E21B34/06

  in wells · CPC title