Control module for a detonation sub and a detonation sub
A control module for a detonation sub includes a control circuit having a switch, a power supply input, a timer circuit, and a detonation signal output electrically connected to a detonator. A power supply is selectively connected in electrical communication to the power supply input. A timer circuit is initialized by activating the switch prior to connecting the power supply and deactivating the switch within an activation time. Once initialized, the timer circuit generates a detonation signal after a detonation time.
1. A control module for a detonation sub, comprising:
a control circuit having a switch, a power supply input, a timer circuit, and a detonation signal output electrically connected to a detonator; and
a power supply that is selectively connected in electrical communication to the power supply input;
wherein the timer circuit is initialized by activating the switch prior to connecting the power supply and deactivating the switch within an activation time, wherein, once initialized, the timer circuit generates a detonation signal after a detonation time.
2. The control module of claim 1 , wherein the switch is a magnetic switch and is actuated by proximity to a magnet.
3. The control module of claim 1 , wherein the control circuit fails to initialize if the switch is not deactivated within the activation time.
4. The control module of claim 1 , wherein the control circuit is configured to deactivate the detonation signal if the control circuit detects a fault.
5. The control module of claim 4 , wherein the fault is detected based on readings from a temperature sensor, a pressure sensor or both a temperature sensor and a pressure sensor.
6. The control module of claim 4 , wherein the control circuit is programmed to detect a fault by periodically performing a diagnostic check.
7. The control module of claim 1 , wherein the control circuit comprises a test mode and an operational mode, the control module accessing the test mode by applying a first voltage and accessing the operational mode by applying a second voltage that is distinct from the first voltage.
8. The control module of claim 1 , wherein the control module is configured such that, after activating the switch, if the timer circuit fails to initialize or is deactivated, the timer circuit can only be initialized by activating the switch prior to connecting the power supply and deactivating the switch within an activation time.
9. A detonation sub, comprising:
a power supply;
a control module, comprising:
a control circuit having a switch, a power supply input, a timer circuit, and a detonation signal output;
wherein the timer circuit is initialized by activating the switch prior to connecting the power supply and deactivating the switch within an activation time, wherein, once initialized, the timer circuit generates a detonation signal after a detonation time;
a detonator electrically connected to receive a detonation signal from the detonation signal output; and
an explosive charge that is detonated by the detonator.
10. The detonation sub of claim 9 , wherein the switch is a magnetic switch and is actuated by proximity to a magnet.
11. The detonation sub of claim 9 , wherein the control circuit fails to initialize if the switch is not deactivated within the activation time.
12. The detonation sub of claim 9 , wherein the control circuit is configured to deactivate the detonation signal if the control circuit detects a fault.
13. The detonation sub of claim 12 , wherein the fault is detected based on readings from a temperature sensor, a pressure sensor or both a temperature sensor and a pressure sensor that are not indicative of a downhole environment.
14. The detonation sub of claim 9 , wherein the control module is configured such that, after activating the switch, if the timer circuit fails to initialize or is deactivated, the timer circuit can only be initialized by activating the switch prior to connecting the power supply and deactivating the switch within an activation time.
15. A slickline tool, comprising:
a slickline having a connection point;
a detonation sub connected to the connection point such that the detonation sub is carried by to the slickline, the detonation sub comprising:
a power supply;
a control module, comprising:
a control circuit having a switch, a power supply input selectively connected to the power supply, a timer circuit, and a detonation signal output;
wherein the timer circuit is initialized by activating the switch prior to connecting the power supply and deactivating the switch within an activation time, wherein, once initialized, the timer circuit generates a detonation signal after a detonation time;
a detonator electrically connected to receive a detonation signal from the detonation signal output; and
an explosive charge that is detonated by the detonator.
16. The slickline tool of claim 15 , wherein the switch is a magnetic switch and is actuated by proximity to a magnet.
17. The slickline tool of claim 15 , wherein the control circuit fails to initialize if the switch is not deactivated within the activation time.
18. The slickline tool of claim 15 , wherein the control circuit is configured to deactivate the detonation signal if the control circuit detects a fault.
19. The slickline tool of claim 18 , wherein the fault is detected based on readings from a temperature sensor, a pressure sensor or both a temperature sensor and a pressure sensor that are not indicative of a downhole environment.
20. The slickline tool of claim 15 , wherein the control module is configured such that, after activating the switch, if the timer circuit fails to initialize or is deactivated, the timer circuit can only be initialized by activating the switch prior to connecting the power supply and deactivating the switch within an activation time.
21. A method of operating a detonation sub, the detonation sub comprising a control circuit having a switch, a power supply input, a timer circuit, and a detonation signal output, the method comprising the steps of:
initiating the timer circuit by:
with the switch activated, connecting a power supply to the power supply input;
with the power supply connected to the power supply input, deactivating the switch within an activation time, such that the timer circuit begins timing a detonation time period, the control circuit being adapted to conduct periodic diagnostic checks during the activation time and the detonation time period to detect faults, and to deactivate if a fault is detected;
lowering the detonation sub downhole to a desired location;
once the detonation time period ends, permitting the control circuit to generate a detonation signal at the detonation signal output if no faults have been detected; and
deactivating the control circuit after the detonation signal has been generated whether detonation has occurred or not.
22. The method of claim 21 , wherein, after activating the switch, if the timer circuit fails to initialize or is deactivated, the timer circuit can only be initialized by activating the switch prior to connecting the power supply and deactivating the switch within an activation time.
23. The method of claim 21 , wherein the timer circuit is deactivated if readings from a temperature sensor, a pressure sensor or both a temperature sensor and a pressure sensor are not indicative of a downhole environment prior to the detonation time period ending.