HYDROMECHANICAL KNIFE PERFORATOR Russian patent published in 2015 - IPC E21B43/114 

FIELD: mining.

SUBSTANCE: perforator comprises pusher-piston, cutting section including working piston with extending cutting disc with its drive to interact with deflecting wedge. Working piston is fitted in working cylinder, cylinder wall being provided with a through lengthwise cut-out opposite said cutting disc. Cutting sections are arranged one after the other. Their working pistons are driven by pusher-piston in one direction and by return spring in opposite direction. Return cylinder piston rod slides inside the spring, cylinder body being engaged with working cylinder. Return cylinder cover has central bore for rod to run there through and circular radial ledge. The latter serves to lock the cover against axial displacement between working cylinder end and inner circular groove made in return cylinder body.

EFFECT: ruled out emergencies, safe return of cutting tool to transportation position.

6 cl, 5 dwg