METHOD OF INSTALLATION OF CEMENT BRIDGE Russian patent published in 2001 - IPC

FIELD: drilling and overhaul of holes of various assignment. SUBSTANCE: method can be used when holes are filled with fluid. Hydraulic giant is sunk on pipe string into hole filled with flushing fluid to lower boundary of interval of installation of cement bridge. Entire portion of grouting mortar is forced through hydraulic giant with flushing fluid. At same time it is pulled on pipe string to upper boundary of interval of installation of cement bridge in period of replacement of flushing fluid with grouting mortar with subsequent wash-off of its surplus and during waiting for hardening. Continuous jet of grouting mortar is formed in direction from axis of pipe string towards space between outer surface of hydraulic giant and wall of well. Initial section of continuous jet of grouting mortar is directed from hydraulic giant at some angle relative to axis of pipe string towards upper boundary of interval of installation of cement bridge. Value of angle is determined by inequality with analytic formula. Hydraulic giant is pulled on pipe string at rate calculated by analytic expression. EFFECT: improved quality of installation of cement bridge. 1 dwg, 2 tbl