PROCESS OPENING PRODUCTIVE POOL WITH DIFFERENTIAL PRESSURE

• Main Authors: FUSS V.A, BAJANOV V.M, DUBROVIN E.F, MATJASHOV S.V, PERMJAKOV A.P, RAKHIMKULOV R.S, KHOMJAKOV A.S, KRYSIN N.I, KRAPIVINA T.N, RJABOV V.G, KOBJAKOV N.I, SALIKHOV R.G, LOBANOV V.A, OPALEV V.A, BRATUKHIN JU.N, GLUKHOV S.D
• Format: Patent
• Language: English
• Published: 27.02.2003
• Edition: 7
• Subjects: EARTH DRILLING; EARTH DRILLING, e.g. DEEP DRILLING; FIXED CONSTRUCTIONS; MINING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS

FIELD: oil and gas industry. SUBSTANCE: process is meant to drill oil, gas or water intake wells to get oil, gas and water. In correspondence with process drill pipe string with drill bit is run into well. Wellhead setup is implemented. Well bore is washed and aerated flushing fluid with gaseous nitrogen, for example, is supplied to drilling bit in process of drilling. Two containers, as minimum, with autonomous pressure gauges are sunk into well prior to lowering of drill pipe string. On completion of flushing of well bore cable bottom-hole pressure gauge is run into well to depth of location of autonomous pressure gauges of drill pipe string. In well bore there are conducted tests aimed at establishment of conditions for depression drilling. With start of flow circulation of flushing fluid with gaseous agent in well bore there are formed in turn at least three modes of supply of aerated flushing fluid which form depression: below planned pressure, equal to planned pressure and above planned pressure. Values of pressure across autonomous and cable bottom-hole pressure gauges are measured under all modes. Time and pressure loss in interval from point of location of pressure gauge to wellhead are established and fixed. Obtained data are used to analyze changes of bottom-hole pressure depending on flow rate of flushing fluid and gaseous agent and graph of such dependence is plotted. Required mode of supply of flushing fluid and gaseous agent is set by this graph. Flushing fluid and gaseous agent are supplied to drill bit under selected mode to keep specified value of depression in productive pool while it is open over its entire thickness. It enhances quality of opening of productive pools with depression with any nonuniformity of properties of solids in productive pools over their thickness, ensures simultaneously reduced time of productive pool opening and prevents emergency situations in process of their driving thanks to high-accuracy determination of required mode of supply of flushing fluid and gaseous agent to secure uninterrupted maintenance of specified value of depression and required distribution of pressures in well bore depending on properties of solids uncovered in drilling process of productive pool over its entire thickness. EFFECT: enhanced quality of opening of productive pools with depression.