SLIT HYDRO-MECHANIC PERFORATOR Russian patent published in 2011 - IPC E21B43/112 

FIELD: oil and gas production.

SUBSTANCE: slit hydro-mechanic perforator consists of hollow case with two pistons in upper part of case with central channel made in body of each piston. The pistons are connected with radial channels above a lower piston by means of a tubular element. In a lower part of the case there is made a lengthwise hole enclosing a rocker with axis cross to the case. Two rolling disks, correspondingly, by one, are arranged at each end of the rocker. The slit hydro-mechanical perforator has a mechanism of rocker transfer into a working position corresponding to a wedge fork-like pusher, and a mechanism for return transfer of the rocker to an initial position. Wedge surface of the pusher contacts an upper end of the rocker on both sides of the upper rolling disk. The slit hydro-mechanic perforator includes two hydro-monitored heads in a body of the lower piston; the heads are hydraulically communicated to a cavity of the case by means of channels; also, the perforator has seats for shutoff balls. One seat is positioned in an upper part of the case, while two others (the main and additional) are positioned in the central channel of the lower piston. The mechanism of return transfer of the rocker has at least two compression springs. The rocker is made in form of a parallelogram, height "H" of which is commensurate, i.e. approximately equal to diameters of the rolling disks and diameter of the case. Central axis of the rocker is positioned on a big diagonal. Surfaces of rocker ends are coaxial to axes of disks and are blending with sides of the parallelogram. The mechanism of rocker return transfer is made as two return plates parallel to each other and arranged movably in the case on different sides of the rocker. In each return plate there is made a skewed slot for a corresponding end of the axis of the upper rolling disk and a lengthwise slit for the axis of the rocker. The return plates are installed and secured with their ends on both sides of the rocker on the wedge fork-like pusher parallel diametrically to plane of rocker positioning in the case. Two compression springs are arranged with opposite directed winding; barrel-like support rollers are made in the body of the case under its hole; also, there is made a channel for free sedimentation of perforation products on bottomhole.

EFFECT: upgraded consumer properties due to optimisation of units and parts of perforator, raised reliability of operation and maintainability.

3 cl, 6 dwg