Wellbore tool with externally-operated ballistic interrupt
A ballistic interrupt assembly may include an interrupt, a magnet coupled to the interrupt, an activator block formed of a magnetizable material and configurable between a non-magnetized state and a magnetized state, a bias element provided between the magnet and the activator block. A bias force of the bias element may be greater than a first magnetic attraction force between the magnet and the activator block in the non-magnetized state. The bias force of the bias element may be less than a second magnetic attraction force between the magnet and the activator block in the magnetized state.
1 . A ballistic interrupt assembly comprising:
an interrupt;
a magnet coupled to the interrupt;
an activator block formed of a magnetizable material and configurable between a non-magnetized state and a magnetized state; and
a bias element provided between the magnet and the activator block;
wherein a bias force of the bias element is greater than a first magnetic attraction force between the magnet and the activator block in the non-magnetized state; and
the bias force of the bias element is less than a second magnetic attraction force between the magnet and the activator block in the magnetized state.
2 . The ballistic interrupt assembly of claim 1 , wherein the interrupt comprises:
an interrupt base formed as a flat disk; and
an interrupt body extending substantially perpendicularly from the interrupt base;
wherein the magnet is fixed to the interrupt base.
3 . The ballistic interrupt assembly of claim 1 , wherein the activator block comprises a ferromagnetic material.
4 . The ballistic interrupt assembly of claim 3 , wherein the activator block comprises a magnetizable steel.
5 . The ballistic interrupt assembly of claim 1 , wherein the magnet comprises neodymium.
6 . The ballistic interrupt assembly of claim 1 , wherein:
the activator block comprises a recess;
a first end of the bias element is received within the recess.
7 . A wellbore tool comprising:
a housing;
an explosive component holder disposed within the housing, the explosive component holder comprising:
a first channel configured for receiving a first explosive component; and
a second channel configured for receiving a second explosive component;
a ballistic interrupt assembly comprising an interrupt movable between a first position and a second position;
wherein in the first position, the interrupt blocks ballistic transfer between the first channel and the second channel such that the wellbore tool is unarmed;
in the second position, the interrupt allows ballistic transfer between the first channel and the second channel such that the perforating gun is armed; and
the interrupt is configured to move from the first position to the second position via application of a magnetic field to the wellbore tool.
8 . The wellbore tool of claim 7 , wherein:
the first explosive component is an initiator; and
the second explosive component is a detonating cord or a booster.
9 . The wellbore tool of claim 7 , wherein the ballistic interrupt assembly further comprises:
a magnet coupled to the interrupt;
an activator block formed of a magnetizable material and configurable between a non-magnetized state and a magnetized state; and
a bias element provided between the magnet and the activator block;
wherein a bias force of the bias element is greater than a first magnetic attraction force between the magnet and the activator block in the non-magnetized state;
the bias force of the bias element is less than a second magnetic attraction force between the magnet and the activator block in the magnetized state;
in first position, at least a portion of the interrupt is positioned between the first channel and the second channel; and
in the second position the interrupt is displaced from between the first channel and the second channel.
10 . The wellbore tool of claim 9 , further comprising a depression formed on an exterior surface of the housing;
wherein the depression is aligned with the activator block.
11 . The wellbore tool of claim 9 , wherein the interrupt comprises:
an interrupt base formed as a flat disk; and
an interrupt body extending substantially perpendicularly from the interrupt base;
wherein the magnet is fixed to the interrupt base.
12 . The wellbore tool of claim 7 , wherein the activator block comprises a ferromagnetic material.
13 . The wellbore tool of claim 7 , wherein the magnet comprises neodymium.
14 . The wellbore tool of claim 9 , further comprising:
an interrupt channel formed in the explosive component holder;
wherein the ballistic interrupt assembly is disposed within the interrupt channel.
15 . The wellbore tool of claim 14 , wherein:
the activator block comprises a recess;
a first end of the bias element is received within the recess.
16 . The wellbore tool of claim 7 , further comprising a detection circuit configured to determine whether the interrupt is in the first position or the second position.
17 . A wellbore tool arming method comprising:
providing a wellbore tool comprising:
a housing;
an explosive component holder disposed within the housing, the explosive component holder comprising:
a first channel configured for receiving a first explosive component; and
a second channel configured for receiving a second explosive component;
a ballistic interrupt assembly comprising:
an interrupt;
a magnet coupled to the interrupt;
an activator block formed of a magnetizable material and configurable between a non-magnetized state and a magnetized state; and
a bias element provided between the magnet and the activator block;
wherein a bias force of the bias element is greater than a first magnetic attraction force between the magnet and the activator block in the non-magnetized state;
the bias force of the bias element is less than a second magnetic attraction force between the magnet and the activator block in the magnetized state; and
the interrupt is movable between a first position in which at least a portion of the interrupt is positioned between the first channel and the second channel and a second position in which the interrupt is displaced from between the first channel and the second channel
moving the interrupt from the first position to the second position.
18 . The wellbore tool arming method of claim 17 , wherein the moving the interrupt from the first position to the second position comprises magnetizing the activator block.
19 . The wellbore tool arming method of claim 18 , wherein magnetizing the activator block comprises:
positioning an electromagnet against an outer surface of the housing; and
activating the electromagnet to generate a magnetic field.
20 . The wellbore tool arming method of claim 19 , wherein the electromagnet is activated for a duration in a range of 1 millisecond to 500 milliseconds.