MULTI BRANCH, LOW PRODUCTION RATE WELL ASSEMBLY FOR SIMULTANIOUSE SEVERAL RESERVOIRS OF DIFFERENT PRODUCTIVITY PRODUCTION, IN ABNORMALLY LOW RESERVOIR PRESSURE CONDITIONS Russian patent published in 2010 - IPC E21B43/14 

FIELD: oil-and-gas industry.

SUBSTANCE: well assembly includes main borehole cased in the top part and equipped with a tail-filter in the bottom part and side boreholes, equipped with tail-filters, and a tubing string descended into the well. At that the main borehole has perforation holes, in interval between the bottom side borehole and the main borehole tail-filter, located in a low productivity reservoir. The main and side boreholes tail-filters located in a high productivity reservoir and placed in radial relatively to the main borehole axis. The tubing string equipped with a circulation valve and a top polished tip in the interval over the top side borehole. In the main borehole and side borehole conjunction points - a mini-window units with landing places, fixed in main borehole casing string snap connections. Over the mini-window top unit located a top production parker and a top landing nipple, interacting with the tubing string top section top polished tip. Between the mini-windows top and bottom units located the tubing string intermediate section with a bottom polished tip, hermetically connected to the mini-window bottom unit. Under the mini-window bottom unit located the tubing string bottom section with a bottom production parker, a landing nipple, a under parker tail and a bowl. At the bottom production parker located over the main borehole tail-filter, under the bottom perforation holes. Mini-window units located in a way, that windows located opposite to the side boreholes entrance holes. The top landing nipple bypass hole is greater than the bottom landing nipple bypass hole.

EFFECT: multi zone well construction reliability increase.

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