FIELD: drilling soil or rock.
SUBSTANCE: system is described for sequentially opening a plurality of close holes in a shank arrangement located in a well; or for the sequential opening of individual groups of holes located in different, but close, places along the shank arrangement to ensure the possibility of hydraulic fracturing in these places. In the arrangement of the shank, sliding couplings are provided, in which annular grooves are made, moreover, these couplings are sequentially moved by a driving device placed in the inner passage of the arrangement of the shank from the closed position, in which they close their corresponding openings, to the open position for opening these openings. Each drive unit contains a soluble plug, which in one embodiment is fixed with shear pins at the upper end of the split spring bushing, which has radially displaceable protrusions that engage with cylindrical grooves of the sliding couplings in accordance with the width of the protrusions. In one embodiment, after actuation of the lowest coupling, the shear pins are cut, resulting in movement of the plug in the collet to prevent the protrusions from escaping from the annular groove of the coupling.
EFFECT: increasing the efficiency of sequential opening of multiple holes located at some distance from each other along the well.
16 cl, 24 dwg
