Drilling fluid recovery when drilling under an obstacle or water body
A system for recovering drilling mud in drilling an underground arcuate path around at least a portion of an obstacle has a conductor casing, a drill pipe surrounded by the conductor casing for at least a portion of an axial length of the drill pipe, a flow line connected to the conductor casing at a downhole position, and a pump coupled to the flow line placed at another downhole position. A volume of drilling mud within the underground arcuate path is pumped from the underground arcuate path to the surface and recovered for recirculation.
1. An apparatus for working an underground arcuate path around at least a portion of an obstacle, comprising
a conducting casing;
a drill pipe surrounded by the conductor casing for at least a portion of an axial length of the drill pipe;
a flow line connected to the conductor casing at a downhole position, wherein said flow line is connected internal to the conductor casing;
a pump coupled to said flow line at another downhole position;
a drill casing surrounding the drill pipe; and
a stabilizer assembly mounted inside the conductor casing and attached to the drill casing.
2. The apparatus according to claim 1 , further including a downhole tooling connected to the drill pipe.
3. The apparatus according to claim 1 , wherein said pump is coupled to an inlet end of said flow line.
4. The apparatus according to claim 3 , wherein said pump is a sump pump.
5. The apparatus according to claim 3 , further including a screen connected to an inlet side of said pump.
6. The apparatus according to claim 1 , wherein said flow line is connected external to the conductor casing.
7. The apparatus according to claim 1 , wherein said stabilizer assembly comprises:
a plurality of struts attached at one end to the drill casing; and
a centralizer casing attached to the other end of the plurality of struts.
8. The apparatus according to claim 7 , wherein said centralizer casing comprises a tubular ring.
9. The apparatus according to claim 7 , wherein the drill casing is concentric with conductor casing.
10. The apparatus according to claim 9 , wherein said flow line is juxtaposed between both the drill casing and said centralizer casing.
11. The apparatus according to claim 10 , further comprising at least one agitator pipe mounted contiguous to said flow line and said centralizer casing.
12. The apparatus according to claim 7 , wherein the drill casing is eccentric with conductor casing.
13. The apparatus according to claim 12 , wherein said flow line is juxtaposed between both the drill casing and said centralizer casing.
14. The apparatus according to claim 13 , further comprising at least one agitator pipe mounted contiguous to said flow line and said centralizer casing.
15. The apparatus according to claim 1 , wherein said pump is coupled to an inlet end of said flow line; and further including at least one agitator mounted contiguous to an inlet to said pump.