DEVICE TO ISOLATE WELL INTERVAL UNDER TEST Russian patent published in 2006 - IPC E21B33/12 

FIELD: hydrogeologic rock survey, particularly to isolate well intervals during test injection performing and underground water pressure measuring.

SUBSTANCE: device comprises latches, body with radial channels, piston arranged inside the body and hollow rod with radial orifice fixedly connected with the piston. Device also has mounting pipe arranged inside the rod, spring-loaded relatively it and connected to rod by spline connection. The mounting pipe has axial channel and radial orifice. Device comprises pusher with thrust pipe, partition located over the piston and perforated pipe arranged between sealing member sections. The hollow rod is provided with bush connected to the rod by spline connection, with rack secured to lower part thereof and rack connected to inner side of device body. Return spring is put on mounting pipe and arranged in space between the piston and partition. Annular groove for pusher installation is formed in lower bush part. Latches cooperating with racks are installed in upper and lower bush parts.

EFFECT: increased operational reliability.

8 dwg