METHOD FOR ACCIDENT PREVENTION AND ELIMINATION, AS WELL AS FOR DRILLING PROBLEMS AVOIDANCE DURING DRILLING OPERATION PERFORMING Russian patent published in 2006 - IPC E21B21/08 

FIELD: well drilling, particularly well drilling with controlling or monitoring pressure or flow of drilling fluid.

SUBSTANCE: method involves including mudding device in drilling string assembly along with setting predetermined drilling fluid pressure drop at drilling bit; lowering drilling string assembly into well; switching-on mud pumps and performing hydrodynamic well wall treatment with mugging device during well drilling. During drilling of well intervals complicated with oil and gas ingress a number of parameters is recorded and controlled with the use of land-based information-measuring system to determine hydrodynamic well wall treatment time. The parameters to be recorded and controlled are gas content in drilling mud at outlet, mechanical drilling speed; drilling mud level in vessels; drilling mud flow rate at inlet/outlet; drilling mud pressure at inlet, drilling mud temperature at inlet, electric resistance of drilling mud at outlet, drilling mud density at inlet and drilling mud flow velocity at outlet. Rotor torque is measured and hook load is also controlled.

EFFECT: prevention of accidents connected with drilling mud absorption by well wall and with well hole fluctuation, increased reliability and efficiency of well hole treatment.

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