Patent ID: 6763892
Filing Date: 2004-07-20
Classification: E21B

Abstract:
A sliding sleeve valve (10) positionable in a drill hole as part of a tube string (18), said drill hole having an annulus (17) between the tube string and the drilled formation, said sliding sleeve valve having a first open position, a second closed position and a third equalizing position between said first open position and said second closed position, the sliding sleeve valve comprising:a. a first segmented tubular body (12) comprising a top segment, a middle segment and a bottom segment co-axially and threadedly engaged, wherein said middle segment includes a first set of wall apertures (15) for desired fluid flow between the tube string and the annulus; b. a closing sleeve (46) comprising a second non-segmented tubular body co-axially mounted within said first body in a sealed and sliding relationship with the first body, said closing sleeve having a second set of wall apertures (56) adapted for communication with said first set of apertures (15) for desired full fluid flow between the tube (18) string and the annulus (17) in said first open position; c. sealing means for sealing undesired leakage flow pathways in a first and a second direction between said first body (12), the closing sleeve (46) and the annulus (17) said sealing means comprising a primary seal, a secondary seal and a tertiary seal located on said undesired fluid flow pathways; and, d. a plurality of equalization ports (58a and 58b) in said closing sleeve disposed in a radial pattern around the closing sleeve and above and below said second set of wall apertures (56), wherein said plurality of equalization ports operate in said third equalizing position and communicate with the first said of wall apertures to equalize pressure across the valve between the first open position and said second closed position, and wherein, the plurality of equalizing ports are substantially smaller than the second set of apertures.