SUBSURFACE DEVICE FOR VERTICAL MOTIONS OF EROSION PERFORATOR Russian patent published in 2001 - IPC

FIELD: oil producing industry, particularly, equipment for tapping of producing formation. SUBSTANCE: device has cylindrical body and hollow rod installed coaxially to body for motion relative to body and rigidly connected in lower part with erosion perforator. Hollow rod forms circular chamber together with body. Sealed part of circular chamber is filled with viscous fluid and accommodates piston rigidly connected with rod and has capillary channel and check valve. Located in circular chamber under hydraulic part with viscous fluid and piston is support. It is rigidly connected with rod for motion relative to body and pressed from below relative to body by spring and has cover in lower sealed part of circular chamber. Cover is movable relative to rod and body. Cover rests on body in extreme lower position. Capillary channel is made of material nonwettable with viscous fluid. EFFECT: higher operating reliability. 2 dwg