WELL CONSTRUCTION METHOD Russian patent published in 2006 - IPC E21B7/00 E21B47/12 E21B43/00 

FIELD: oil industry, particularly for well construction and completion.

SUBSTANCE: method involves drilling well bore up to productive formation roof reaching; arranging bottomhole apparatus in protective case in lower part from outer casing pipe side; communicating bottomhole apparatus with day surface by cable; lowering casing pipe along with cable fastening to outer side of casing pipe; isolating casing pipe interior from protective bottomhole apparatus case interior during casing pipe lowering and cementing; cementing hole annuity; exposing productive formation after casing pipe cementing by drilling-in productive formation with the use of drilling bit having lesser diameter through casing pipe under downbottom parameter control; communicating protective case interior and downhole apparatus with casing pipe interior during drilling-in operation.

EFFECT: increased charge period, possibility to perform measurements with on-line instruments.

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