HYDRAULIC BOREHOLE EXPANDER Russian patent published in 2022 - IPC E21B7/28 

FIELD: oil and gas wells construction.

SUBSTANCE: invention relates to the field of construction of oil and gas wells, namely, to devices for expanding the wellbore. The hydraulic borehole reamer contains a body with longitudinally made through grooves, in which retractable blades are pivotally mounted on the axes, reinforced on the outside with hard alloy, a spring-loaded hollow rod with a piston fixed on it, having flushing holes, an annular conical thickening, made on the outer surface of the hollow rod with the possibility blade interaction. The device contains lugs radially directed to the blades, and in each blade there are internal grooves - a longitudinal one for the corresponding lug and a shaped transverse groove for the guide pin installed in the through hole of the upper part of the lug. The base of each lug is fixed in the conical thickening of the hollow rod, and the upper part is articulated with the corresponding blade of the device by means of a guide pin on one side and internal grooves of the blade on the other side. The figured transverse groove of the blade has an arcuate shape, ensuring constant mating of the working surface of the lug with the inner surface of the groove of the blade when it is extended and returned to its original position.

EFFECT: forced return of the blades of the device from the working position to the transport is achieved.

1 cl, 7 dwg