METHOD OF CONTROL OVER WELL BORING PARAMETERS AND CONFIGURATION OF DRILLING STRING BOTTOM FOR IMPLEMENTATION OF PROPOSED METHOD Russian patent published in 2012 - IPC E21B44/00 E21B21/00 

FIELD: oil and gas production.

SUBSTANCE: proposed method comprises adjusting and maintaining optimum differential pressure by defining and adjusting flushing fluid density, allowing fro mechanical rate of boring depending on formation drillability index. In compliance with proposed method, drilling parameters are controlled directly at well bottom. Here, adjusted are differential pressure above screw device bit and flushing fluid density by mounting separator there above. Note here that all components feature equal diameter while drilling rate is optimised by calculation of drilling parameters. The latter include bit rpm, load on bit, flushing fluid flow rate to be defined from mathematical expressions. Besides, drilling string bottom comprises bit, sludge trap and drilling tubes. In compliance with this invention, screw device and separator are mounted above the bit. Note here that diameter of external generator of screw, separator and other components should be equal.

EFFECT: higher efficiency of rock breaking.

2 cl, 1 dwg