FIELD: hydraulics.
SUBSTANCE: invention relates to a downhole tool that is used in hydraulic fracturing. The lip valve has a valve body, a sliding sleeve and a clamping sleeve. The valve body has one or more fluid openings in its upper borehole sidewall portion. The sliding sleeve is movable between a closed position upbore in which one or more fluid openings are closed, and an open position downhole in which one or more fluid openings are open. The clamping sleeve contains an expandable metal part near the end of the clamping sleeve located up the wellbore, and a ball seat having a ball seat surface that is inclined inward in a radial direction from top to bottom along the wellbore at an acute angle to the longitudinal axis of the clamping sleeve. The expandable part is configured to expand outward in a radial direction under pressure acting on the ball seated in the specified seat, which forms a seal at the point of contact between the clamping sleeve and the longitudinal channel of the sliding sleeve when the clamping sleeve is located in the sliding sleeve. To perform the method, the flow of the clamping sleeve is initiated downward into the wellbore and is fixed in the channel of the sliding sleeve, the ball flows downward into the wellbore and the ball is seated in the saddle. A first fluid pressure is applied to press the ball against the seat and expand the portion of the clamping sleeve in the area of the seat radially outward to form a seal at the point of contact between the clamping sleeve and the sliding sleeve. A second fluid pressure is applied to shear the shear pins and move the sliding sleeve down the wellbore and open the hole.
EFFECT: increased reliability of the sequential engagement and displacement of the valve.
29 cl, 76 dwg, 1 tbl
