Abstract: The method of well construction includes the steps of drilling the rock and consolidating it with a conductor casing, a surface casing string and a flow string, and isolating the troublesome zones of the well with profile pipes being reamed in the course of their setting. The reaming of the profile pipes is effected by building up a pressure drop across them and subsequently expanding them. The drilling of the rock after the casing-in of the well with the conductor casing and the surface casing string is preformed with a bit of one and the same diameter, with the troublesome zones being reamed to a diameter equalling the outer diameter of the reamed profile pipes which are successively set in all the troublesome zones of the well as they are exposed by the drilling.

Abstract: There is claimed a method for isolating intake beds in drill holes (wells), wherein a cement slurry is pumped into a drill pipe string from a well mouth and flash setting and thickening of the cement slurry is ensured once it has left the drill pipe string and a separated phase of lower density is directed to the well mouth via an annular space of the well above a lost circulation zone. A device for carrying same into effect is also claimed.