System and method for coupling an impregnated drill bit to a whipstock
View Patent ↗A system and method to facilitate the drilling of one or more lateral wellbores while eliminating one or more trips downhole. The system utilizes a drilling assembly comprising an impregnated drill bit or other suitable drill bit. The impregnated drill bit is coupled to a whipstock by a connector for deployment downhole in a single trip. The connector comprises a separation device which facilitates disconnection of the impregnated drill bit from the whipstock once the whipstock is anchored at a desired downhole location.
1. A system for facilitating drilling a sidetracked wellbore, comprising:
an impregnated drill bit comprising a body and a plurality of cutting surfaces separated by junk slots, at least a portion of the impregnated drill bit comprising diamond impregnated material;
a whipstock; and
a connector coupling the whipstock to the impregnated drill bit, the connector comprising a separation device to facilitate disengagement of the impregnated drill bit from the whipstock after the whipstock is anchored at a desired downhole location,
wherein the impregnated drill bit comprises a recess for receiving the connector, the recess being lined with a tougher material relative to a surrounding material of the impregnated drill bit.
2. The system as recited in claim 1 , wherein the tougher material comprises tungsten and the surrounding material comprises tungsten carbide.
3. The system as recited in claim 1 , wherein the tougher material comprises steel.
4. The system as recited in claim 1 , wherein the tougher material is fused with the surrounding material during formation of the impregnated drill bit.
5. The system as recited in claim 1 , wherein the tougher material is in the form of a sleeve affixed in the recess of the impregnated drill bit.
6. The system as recited in claim 1 , further comprising a turbine including a turbine sleeve coupled to the impregnated drill bit.
7. The system as recited in claim 6 , wherein the turbine sleeve is welded to the impregnated drill bit.
8. The system as recited in claim 6 , wherein the turbine is rotatably locked until the whipstock is anchored at the desired downhole location.
9. The system as recited in claim 1 , wherein the impregnated drill bit also has one or more cutting elements including one or more polycrystalline diamond cutters.
10. The system as recited in claim 1 , wherein the separation device is located proximate a top end portion of the whipstock.
11. The system as recited in claim 1 , wherein the connector is welded to the whipstock.
12. A system for drilling a wellbore, comprising:
a drill bit formed as a composite drill bit and comprising a body, cutting elements, a plurality of blades, and a whipstock connector recess sized to receive a whipstock connector pin, the whipstock connector recess being bounded by a radially inward portion formed of a tougher material than a surrounding material of the drill bit;
a whipstock; and
the whipstock connector pin coupling the whipstock to the composite drill bit, the whipstock connector pin comprising a shear region to facilitate disengagement of the drill bit from the whipstock once the whipstock is anchored at a desired location.
13. The system as recited in claim 12 , wherein the drill bit comprises a diamond impregnated material.
14. The system as recited in claim 12 , wherein the drill bit comprises a matrix material.
15. The system as recited in claim 12 , wherein the whipstock connector pin comprises a head which extends into an opening formed in an upper end of the whipstock, the head being welded into the opening.
16. The system as recited in claim 12 , wherein the whipstock connector pin is held within the whipstock connector recess of the composite drill bit by a removable retainer.
17. The system as recited in claim 16 , wherein the removable retainer is held in place by a removable fastener.
18. The system as recited in claim 12 , wherein the cutting elements comprise polycrystalline diamond cutters.
19. The system as recited in claim 12 , wherein the radially inward portion comprises a primarily metal material and the surrounding material comprises a metal carbide material.
20. The system as recited in claim 12 , wherein the radially inward portion comprises a primarily tungsten material and the surrounding material comprises a tungsten carbide material.
21. The system as recited in claim 12 , wherein the blades are formed from a diamond impregnated material.
22. A method to facilitate drilling a sidetracked wellbore, comprising:
coupling an impregnated drill bit of a drilling assembly to a whipstock via a connector;
locking a turbine of the drilling assembly from rotation with a locking member;
deploying the drilling assembly and the whipstock in a wellbore;
anchoring the whipstock at a desired location;
disengaging the drilling assembly from the whipstock by separating a separable portion of the connector;
shearing the locking member to allow rotation of the turbine; and
commencing drilling a sidetracked wellbore with the drilling assembly.
23. The method as recited in claim 22 , wherein the deploying, anchoring, disengaging, shearing and commencing are performed in a single trip downhole.
24. The method as recited in claim 22 , further comprising positioning an end portion of the connector in a recess of the impregnated drill bit, and protecting the drill bit from detrimental contact stresses by lining the recess with a tougher material than a surrounding drill bit material.
25. The method as recited in claim 22 , wherein coupling the impregnated drill bit of the drilling assembly to the whipstock comprises coupling the connector to a turbine sleeve of the turbine.
26. The method as recited in claim 22 , wherein coupling the impregnated drill bit of the drilling assembly comprises coupling the impregnated drill bit to the whipstock with the connector in the form of a pin.
27. The method as recited in claim 22 , wherein the separable portion of the connector is positioned proximate a top end portion of the whipstock.