Differential-pressure sliding sleeve for staged fracturing of sidetrack horizontal wells

The utility model discloses a differential-pressure sliding sleeve for the staged fracturing of sidetrack horizontal wells, which comprises an upper joint, an outer cylinder, a lower joint, an inner sliding sleeve, a shear pin and a locking ring, wherein the two ends of the outer cylinder are respectively in threaded connection with the upper joint and the lower joint; the upper joint and the lower joint are respectively provided with a thread connected with an oil tube; the inner sliding sleeve is arranged in the outer cylinder, and the vertical pressure-bearing area of the upper end face of the inner sliding sleeve is greater than that of the lower end face; the side face of the outer cylinder is provided with a plurality of diversion trenches; the inner sliding sleeve and the outer cylinder are fixedly connected through the shear pin; the outer circumferential surface of the inner sliding sleeve is provided with a circular groove, and the locking ring is embedded in the circular groove; and the lower joint is provided with a support step for preventing the sliding sleeve from sliding out. By using the technical scheme in the utility model, the sliding sleeve is opened by using the differential pressure between the upper and lower end faces of the inner sliding sleeve, thereby solving the problem that a ball-pitching sliding sleeve can not be applied to the first-layer staged fracturing of sidetrack horizontal wells; and the sliding sleeve is safe and reliable, and convenient to remove and install.