Rotary steerable drilling tool

A rotary orientable drilling tool for use in combination with a MWD tool, the rotary orientable drilling tool comprising:

• (a) a mandrel;
• (b) an asymmetrical housing mounted on the mandrel for rotation in relation to the mandrel;
• and
• (c) a first sensor on the mandrel that is sensitive to the rotary orientation of the housing in relation to the mandrel, the first sensor providing a signal indicative of the rotary orientation of the housing on the mandrel to a communication link.

A drill string, comprising:

• (a) a mandrel;
• (b) a housing mounted on the mandrel for rotation in relation to the mandrel;
• (c) an adjustable offset mechanism on the housing, the adjustable offset mechanism being surface adjustable to move the rotary steerable drilling tool to and from a straight ahead drilling position and an offset drilling position;
• (d) a drill bit terminating the drill string;
• and
• (e) a stabilizer on the drill string between the drill bit and mandrel.

A drill string, comprising:

• (a) a mandrel;
• (b) a housing mounted on the mandrel for rotation in relation to the mandrel;
• (c) an adjustable offset mechanism on the housing, the adjustable offset mechanism being surface adjustable to move the rotary steerable drilling tool to and from a straight ahead drilling position and an offset drilling position;
• (d) plural pistons radially mounted in the housing, the plural pistons being radially adjustable by actuation of the mandrel;
• (e) a drill bit terminating the drill string;
• and
• (f) a stabilizer on the drill string between the drill bit and mandrel.

A drill string, comprising:

• (a) a mandrel;
• (b) a housing mounted on the mandrel for rotation in relation to the mandrel;
• (c) an adjustable offset mechanism on the housing, the adjustable offset mechanism being surface adjustable to move the rotary steerable drilling tool to and from a straight ahead drilling position and an offset drilling position;
• (d) first piston and second piston radially mounted in the housing, the first piston and second piston being radially adjustable by actuation of the mandrel;
• the first piston being extended and the second piston being retracted in the straight ahead drilling position, and the first piston being retracted and the second piston being extended in the offset drilling position;
• (e) a drill bit terminating the drill string;
• and
• (f) a stabilizer on the drill string between the drill bit and mandrel.

A drill string, comprising:

• (a) a mandrel;
• (b) a housing mounted on the mandrel for rotation in relation to the mandrel;
• (c) an adjustable offset mechanism on the housing, the adjustable offset mechanism being surface adjustable to move the rotary steerable drilling tool to and from a straight ahead drilling position and an offset drilling position;
• (d) first piston and second piston radially mounted in the housing, the first piston and second piston being radially adjustable by actuation of the mandrel;
• the first piston being extended and the second piston being retracted in the straight ahead drilling position, and the first piston being retracted and the second piston being extended in the offset drilling position;
• (e) a cam sleeve mounted on the mandrel for actuating the first piston and second piston;
• (f) a drill bit terminating the drill string;
• and
• (g) a stabilizer on the drill string between the drill bit and mandrel.

A drill string, comprising:

• (a) a mandrel;
• (b) a housing mounted on the mandrel for rotation in relation to the mandrel;
• (c) an adjustable offset mechanism on the housing, the adjustable offset mechanism being surface adjustable to move the rotary steerable drilling tool to and from a straight ahead drilling position and an offset drilling position;
• (d) first piston and second piston radially mounted in the housing, the first piston and second piston being radially adjustable by actuation of the mandrel;
• the first piston being extended and the second piston being retracted in the straight ahead drilling position, and the first piston being retracted and the second piston being extended in the offset drilling position;
• (e) a cam sleeve mounted on the mandrel for actuating the first piston and second piston;
• (f) wings mounted on the mandrel and operable by fluid pressure within the mandrel into a radially extended position;
• (g) the wings cooperating with the cam sleeve to drive the second piston outward and retract the first piston when the wings are in the extended position;
• (h) a drill bit terminating the drill string;
• and
• (i) a stabilizer on the drill string between the drill bit and mandrel.

A drill string, comprising:

• (a) an upper mandrel;
• (b) a lower mandrel slidably connected to the upper mandrel by splines;
• (c) a housing mounted on the upper mandrel for rotation in relation to the upper mandrel;
• (d) an adjustable offset mechanism on the housing, the adjustable offset mechanism being surface adjustable to move the rotary steerable drilling tool to and from a straight ahead drilling position and an offset drilling position;
• (e) a drill bit terminating the drill string;
• and
• (f) a stabilizer on the drill string between the drill bit and lower mandrel.

A method of drilling a hole, the method comprising the steps of:

• (a) rotating a drill string while the drill string is bottomed out in the hole;
• (b) pulling the drill string off bottom;
• (c) offsetting the drill string in the hole above a fulcrum to offset the drill bit in the hole;
• and
• (d) continuing to rotate the drill string with the drill string bottomed out in the hole and the drill bit offset in the hole.