Fluid control valve for rotary steerable tool
OwnerRichard Huttoninventor
Life of this patent
Estimating the term…
Abstract
A downhole tool control system for a drill string rotary steerable tool that includes a body having an inner chamber, a piston gallery extending between the inner chamber and a piston port, and an exhaust gallery extending between the inner chamber and an exhaust port. A spool in the inner chamber is movable into a plurality of positions to direct and control the timing and duration of the flow of drilling fluid to energize pistons of the rotary steerable tool, and to de-energize the pistons. The spool includes a first passage in fluid communication with a drilling fluid inlet port but not the exhaust port, and a second passage in fluid communication with the exhaust port but not the drilling fluid inlet port.
Claims20
A fluid control valve for a rotary steerable tool comprising:
- a fluid control valve body having an inner chamber, a piston gallery extending between the inner chamber and a piston port, and an exhaust gallery extending between the inner chamber and an exhaust port, the inner chamber having a drilling fluid inlet port;
- a spool in the inner chamber, the spool having a first passage in fluid communication with the drilling fluid inlet port but not the exhaust port, and a second passage in fluid communication with the exhaust port but not the drilling fluid inlet port;
- wherein the spool is movable to an actuation position in the inner chamber such that the first passage forms a fluid flow path between the piston gallery and the drilling inlet port, and also movable to a discharge position such that the second passage forms a fluid flow path between the piston gallery and the exhaust port.
A method of controlling a rotary steerable tool using a fluid control valve, the method comprising:
- providing a fluid control valve body having an inner chamber, a piston gallery extending between the inner chamber and a piston port, and an exhaust gallery extending between the inner chamber and an exhaust port, the inner chamber having a drilling fluid inlet port, and providing a spool in the inner chamber, the spool having a first passage in fluid communication with the drilling fluid inlet port but not the exhaust port, and a second passage in fluid communication with the exhaust port but not the drilling fluid inlet port;
- receiving fluid from the fluid inlet port into the first passage and discharging the fluid into the piston gallery, when the spool is in an actuation position;
- and
- receiving fluid from the piston gallery into the second passage and discharging the fluid into the exhaust gallery when the spool is in a discharge position.
A rotary steerable tool fluid control valve comprising:
- a fluid control valve body having an inner chamber, a piston gallery extending between the inner chamber and a piston port, and an exhaust gallery extending between the inner chamber and an exhaust port, the inner chamber having a drilling fluid inlet port;
- a spool in the inner chamber, the spool having a first passage in fluid communication with the drilling fluid inlet port but not the exhaust port, and a second passage in fluid communication with the exhaust port but not the drilling fluid inlet port;
- wherein the first passage has a length and a first passage minimum flow cross sectional area at some point along its length, wherein the second passage has a length and a second passage minimum flow cross sectional area at some point along its length, wherein the exhaust gallery has a length and an exhaust gallery minimum flow cross sectional area, and wherein both the exhaust gallery minimum flow cross sectional area and the second passage minimum flow cross sectional area are greater than at least half of the first passage minimum flow cross sectional area.
Dependencies are inferred from the claim text.