METHOD OF WELLBORE CLEANING Russian patent published in 2001 - IPC

FIELD: drilling and major repairs of wells of various applications; applicable in cases of well filled with drilling mud. SUBSTANCE: method includes formation of continuous jet with the help of hydraulic giant with slotted nozzle closed over cross-section perimeter and lowered to lower boundary of cleaned interval. Continuous jet is formed from entire flow of drilling mud in direction from axis of pipe string between external surface of hydraulic giant and well wall. Initial part of continuous jet is directed at an angle to upper boundary of cleaned interval. The angle value is determined by mathematical inequality. Lifting of hydraulic giant on pipe string is effected at speed also calculated with consideration of mathematical inequality. Upon reaching the upper boundary of cleaned internal by hydraulic giant well is washed. EFFECT: improved quality of wellbore cleaning. 1 dwg, 1 ex