DEVICE FOR WELL BORE PERFORATION IN THE CASE OF LOW RESERVOIR PRESSURE Russian patent published in 2007 - IPC E21B43/11 

FIELD: oil and gas production, particularly perforators and permeators.

SUBSTANCE: device comprises tubular body connected to piston and wedge pusher provided with tool holders and working cutters. Support body cooperates with tool holders from below. Activating slider body is installed so that the slider body may slide with respect to tubular body in longitudinal direction. Base fixedly secured to support body is installed outside piston so that it may slide in longitudinal direction upwards with respect to the piston. Tubular body and slider body are fixed to piston and pipe string correspondingly. Upper part of tubular body has radial channels, which may be hermetically closed with slider body as slider body moves downwards. Body is retained with shear member relatively the piston and is provided with technological cylindrical pipe located from top part thereof. The cylindrical pipe hermetically encloses tubular body and has conical projection expanding upwards and created on upper end thereof. Cylindrical pipe has reciprocating and rotating anchor. Anchor comprises body with guiding pin, centrators spring-loaded outwards and slips pressed inside. In working position the slips may cooperate with conical extension. Grooves cooperating with guiding pin are formed in outer surface of cylindrical pipe. Each groove includes longitudinal short section and long section connected with each other through shaped sections. Upper shaped section is communicated with long section center and is provided with manufacturing recess.

EFFECT: increased operational reliability.

3 dwg