Apparatus for centralization of downhole milling bit
Aspects of the subject technology relate to apparatus and methods for removing obstructions that may block a wellbore passageway. Such obstructions may have been caused by the occurrence of an undesired event. Examples of such undesired events include debris blocking a tube or casing or the failure of a valve that controllably links one part of a wellbore to another part of the wellbore. In either instance, a drilling and/or milling operation may be required to break through the obstruction. Tools of the present disclosure may include milling or drilling bits that are used to center a bit that is used to mill and/or drill through an obstruction.
1 . A wellbore tool comprising:
a centering element of the wellbore tool;
a cutting element of the wellbore tool, wherein:
the centering element of the wellbore tool attaches to the cutting element of the wellbore tool based on a first portion of the centering element being passed through a hole in the cutting element; and
a retention mechanism that controllably latches the centering element to the cutting element, wherein:
the centering element rotates with the cutting element when the retention mechanism is in a latched position;
the centering element does not rotate with the cutting element when the retention mechanism is in an unlatched position, and
the cutting element moves downhole as the centering element stays in a fixed position when the retention mechanism is in the unlatched position based on a downhole force being applied to the cutting element.
2 . The wellbore tool of claim 1 , wherein the wellbore tool is configured to be deployed in a wellbore and placed at a wellbore obstruction and operation of the cutting element is initiated to cut into the obstruction.
3 . The wellbore tool of claim 1 , further comprising:
a drill shaft that is coupled to the cutting element.
4 . The wellbore tool of claim 3 , wherein a tip portion of the centering element includes threads that drill into a wellbore obstruction when the centering element rotates.
5 . The wellbore tool of claim 1 , wherein the centering element includes a keyed shaped portion that fits into a keyed shaped hole of the cutting element.
6 . The wellbore tool of claim 5 , wherein the retention mechanism includes friction associated with the keyed shaped portion of the centering element fitting into the keyed shaped hole of the cutting element.
7 . The wellbore tool of claim 1 , wherein the retention mechanism moves from the latched position to the unlatched position based on a force applied to the cutting element.
8 . The wellbore tool of claim 1 , wherein the retention mechanism includes one or more clamps that engage a portion of the centering element.
9 . A method comprising:
attaching a centering element of a wellbore tool to a cutting element of the wellbore tool based on a first portion of the centering element being passed through a hole in the cutting element;
engaging a retention mechanism that controllably latches the centering element to the cutting element;
placing the centering element of the wellbore tool at an obstruction;
disengaging the retention mechanism that latches the tool centering element to the tool cutting element; and
initiating operation of the wellbore tool to cause the cutting element to contact the obstruction and cut into the obstruction, wherein:
the centering element rotates with the cutting element when the retention mechanism is in a latched position;
the centering element does not rotate with the cutting element when the retention mechanism is in an unlatched position, and
the cutting element moves downhole as the centering element stays in a fixed position when the retention mechanism is in the unlatched position based on a downhole force being applied to the cutting element.
10 . The method of claim 9 , further comprising:
deploying the wellbore tool in a wellbore;
placing the wellbore tool at the obstruction, thereby causing the cutting element to be positioned at the obstruction; and
initiating operation of the cutting element to cut into the obstruction.
11 . The method of claim 10 , wherein the placing of the wellbore tool at the obstruction includes forcing the centering element toward the obstruction.
12 . The method of claim 10 , wherein the placing of the wellbore tool at the obstruction includes drilling at least an end portion of the centering element into the obstruction.
13 . The method of claim 9 , wherein a drill shaft is coupled to the cutting element.
14 . The method of claim 9 , wherein the centering element includes a keyed shaped portion that fits into a keyed shaped hole of the cutting element.
15 . The method of claim 14 , wherein the retention mechanism includes friction associated with the keyed shaped portion of the centering element fitting into the keyed shaped hole of the cutting element.
16 . The method of claim 9 , wherein the retention mechanism moves from the latched position to the unlatched position based on a force applied to the cutting element.
17 . The method of claim 9 , wherein the retention mechanism includes one or more clamps that engage a portion of the centering element.
18 . The method of claim 9 , wherein a tip portion of the centering element includes threads that drill into a wellbore obstruction when the centering element rotates.
19 . The method of claim 9 , further comprising:
rotating the wellbore tool centering element in a first direction to engage the retention mechanism; and
rotating the centering element in a second direction to disengage the retention mechanism.
20 . The method of claim 19 , further comprising:
rotating the cutting element to cut into the obstruction.