Updated steering pad control device

1 . A system for controlling steering pads of a rotary steerable drilling system comprises:

a valve seat comprising a central channel therethrough and a plurality of channels therethrough, wherein each of the plurality of channels corresponds to one of the steering pads, with fluid flow through the channels controlling activation of the steering pads; and

a steering valve comprising a closed portion and an open portion, wherein the open portion comprises a cut-off-portion and at least one flow portion;

wherein:

the steering valve is disposed adjacent to the valve seat, with a first face of the steering valve adjacent to a second face of the valve seat, and is configured to rotate relative to the valve seat to control flow of fluid through the plurality of channels of the valve seat;

the steering valve comprises a recess disposed in the closed portion;

the steering valve comprises a blind notch recess extending radially in the cut-off portion, wherein the blind notch recess and the recess are not connected;

for each of the plurality of channels, the valve seat comprises a notch extending radially outward from the central channel, wherein each notch extends towards but does not intersect the corresponding channel; and

the steering valve is configured so that, responsive to the steering valve being oriented relative to the valve seat to cover all of the plurality of channels, one of the notches of the valve seat overlaps with the blind notch recess of the steering valve.

2 . The system of claim 1 , wherein:

the blind notch recess comprises an inner end distance and an outer end distance, wherein the outer end distance is radially outward of the inner end distance;

the outer end distance extends radially outward sufficiently to allow for overlap with the plurality of channels in the valve seat when properly oriented; and

each notch extends radially outward beyond the inner end distance.

3 . The system of claim 1 , wherein the steering valve is configured to be rotationally oriented with respect to the valve seat to control activation of the steering pads, and wherein the orientation can allow for one pad to be active while two pads are inactive, two pads to be active while one pad is inactive, or all pads to be inactive.

4 . The system of claim 1 , wherein overlap of one of the notches of the valve seat with the blind notch recess is configured to bleed off fluid pressure from the steering pad corresponding to the channel covered by the cut-off portion.

5 . The system of claim 1 , wherein responsive to one or more steering pad being deactivated, the one or more deactivated steering pad is in fluid communication with the central channel of the valve seat.

6 . The system of claim 1 , wherein:

the channels of the valve seat are approximately evenly spaced;

all of the plurality of channels in the valve seat are similar, and all notches in the valve seat are similar;

each channel is positioned radially on the valve seat at a distance allowing overlap with the at least one flow portion of the steering valve; and

a central channel of the steering valve overlaps with the central channel of the valve seat.

7 . The system of claim 1 , wherein the at least one flow portion of the steering valve comprises a first flow portion and a second flow portion, wherein the cut-off portion is disposed between the first flow portion and the second flow portion.

8 . The system of claim 7 , wherein:

the closed portion comprises:

a first end abutting a second end of the open portion; and

a third end positioned opposite the first end and abutting a fourth end of the open portion; and

the open portion comprises:

the second end abutting the first end of the closed portion; and

the fourth end positioned opposite the third end and abutting the third end of the closed portion;

wherein the cut-off portion is positioned between the second end and the fourth end; and

wherein the open portion comprises: the first flow portion extending between the second end of the open portion and a fifth end of the cut-off portion; and the second flow portion extending between a sixth end of the cut-off portion and the fourth end of the open portion, wherein the sixth end is positioned opposite the fifth end with respect to the cut-off portion.

9 . A method of operating a rotary steerable drilling system comprises:

positioning the rotary steerable drilling system of claim 1 in a subterranean formation to steer a drill string to form a wellbore in the subterranean formation; and

adjusting an orientation of the steering valve of the rotary steerable drilling system to cover all of the channels of the valve seat to prevent flow of fluid through the channels and deactivate all of the steering pads of the rotary steerable drilling system.

10 . The method of claim 9 , wherein the blind notch recess of the steering valve overlaps with one of the notches of the valve seat, and wherein adjusting an orientation of the steering valve comprises bleeding fluid pressure from the steering pad corresponding to the overlapping notch.

11 . The method of claim 10 , wherein bleeding fluid pressure from the steering pad corresponding to the overlapping notch comprises placing the steering pad corresponding to the overlapping notch in fluid communication with the blind notch recess, the overlapping notch, and the central channel of the valve seat.

12 . The method of claim 10 , wherein the channels of the valve seat other than the channel corresponding to the overlapping notch overlap with the recess in the steering valve, and wherein adjusting an orientation of the steering valve comprises bleeding fluid pressure from the steering pads corresponding to the other channels.

13 . The method of claim 12 , wherein bleeding fluid pressure from the steering pads corresponding to the other channels comprises placing the corresponding steering pads in fluid communication with the recess of the steering valve and the central channel of the valve seat.

14 . The method of claim 10 , wherein adjusting an orientation of the steering valve comprises covering one of the channels with the cut-off portion of the steering valve and covering the remaining channels with the closed portion of the steering valve; and wherein fluid pressure is bled from the steering pad corresponding to the channel covered by the cut-off portion through the blind notch recess and the overlapping notch.

15 . The method of claim 9 , further comprising adjusting the orientation of the steering valve to activate at least one of the steering pads, wherein the blind notch recess of the steering valve does not align with any of the notches of the valve seat.

16 . The method of claim 15 , wherein:

the plurality of channels of the valve seat comprises three channels;

the closed portion of the steering valve covers one or two of the three channels; and

the at least one flow portion of the steering valve overlaps with one or two of the three channels.

17 . The method of claim 15 , wherein adjusting the orientation of the steering valve to activate at least one of the steering pads comprises uncovering the channel corresponding to the at least one activated steering pad and flowing fluid therethrough to the at least one activated steering pad; and bleeding fluid pressure from the steering pads other than the at least one activated steering pad.

18 . The method of claim 17 , wherein bleeding fluid pressure from the other steering pads comprises placing each of the other steering pads in fluid communication with the recess of the steering valve and the central channel of the valve seat.

19 . A system for controlling steering pads of a rotary steerable drilling system comprises:

a valve seat comprising a central channel therethrough and a plurality of channels therethrough, wherein each of the plurality of channels corresponds to one of the steering pads, with fluid flow through the channels controlling activation of the steering pads; and

a steering valve comprising a closed portion and an open portion, wherein the open portion comprises a cut-off-portion and at least one flow portion;

wherein:

the steering valve is disposed adjacent to the valve seat, with a first face of the steering valve adjacent to a second face of the valve seat, and is configured to rotate relative to the valve seat to control flow of fluid through the plurality of channels of the valve seat;

the steering valve comprises a recess disposed in the closed portion;

the steering valve comprises a blind notch recess extending radially in the cut-off portion, wherein the blind notch recess and the recess are not connected;

for each of the plurality of channels, the valve seat comprises a notch extending radially outward from the central channel, wherein each notch extends towards but does not intersect the corresponding channel; and

responsive to the steering valve covering all of the plurality of channels, fluid pressure of one of the steering pads bleeds off through overlap of the blind notch recess and one of the notches in the valve seat to the central channel of the valve seat; and the fluid pressure of the remaining steering pads bleeds off through overlap of the corresponding channels with the recess in the steering valve.

20 . The method of claim 19 , wherein:

the blind notch recess comprises an inner end distance and an outer end distance, wherein the outer end distance is radially outward of the inner end distance;

the outer end distance extends radially outward sufficiently to allow for overlap with the plurality of channels in the valve seat when properly oriented;

each notch extends radially outward beyond the inner end distance;

each channel is positioned radially on the valve seat at a distance allowing overlap with the at least one flow portion of the steering valve; and

the at least one flow portion of the steering valve comprises a first flow portion and a second flow portion, wherein the cut-off portion is disposed between the first flow portion and the second flow portion.