DRILL COLUMN FOR DRILLING OF WELLS IN HIGHLY GAS-BEARING BEDS Russian patent published in 2013 - IPC E21B10/42 

FIELD: oil and gas industry.

SUBSTANCE: drill column comprises a body with a stepped outer surface, a working tip connected with it by means of a unit of torque transfer with the possibility of limited axial displacement, with a jacket and washing channels, and check valves installed in them. The column is equipped with a protective bushing and an axial drive for the working tip, installed in the cavity formed by the body and the protective bushing between the opposite ends of the jacket and the end of the protective bushing rigidly connected to the body. The axial drive is made in the form of a compression spring or in the form of a disc of an elastic material. At the same time each washing channels of the working tip and the end of the stop element of the check valve installed in it are arranged with a congruous conical shape.

EFFECT: improved efficiency of column operation by provision of reliable actuation of stop elements in check valves.

3 cl, 1 dwg