Fine Control Pressure Drilling Technique In Tarim Carbonate Super Deep Application Of Horizontal Wells

Pressure control drilling technology called MPD (Managed Pressure Dirlling)technology, referred to as managed pressure drilling. By controlling the density of drillingfluid, equivalent circulating density and wellhead back pressure, so that the bottom holepressure to maintain a relatively constant. Its function is: one is the effective protection of oiland gas reservoir; two is in the" narrow pressure window" condition，can reduce the dirllingwells, well leakage and other downhole complicated conditions，improve the well controlsafety; three is to extend the naked eye length, increasing the casing setting depth, thus makingit possible to reduce a even more levels of casing; four is to avoid underground blowout; fivecan effectively reduce the dirlling cost.The pressure control drilling, Pb=Pm+Pl+Pa. By adjusting the wellhead back pressurecan change the bottom hole pressure, both simple and fast. In the pressure control drilling,dirlling fluid density may be lower than the pore pressure，but this did not speak inunderbalanced operation, because the bottom hole pressure is still higher than that offormation pore pressure. For safety in carbonate reservoir through the multiple cracks ordevelopmental empty reservoir, usually in such reservoirs prone to high pressure, highhydrogen sulifde，high temperature reservoir in Tarim carbonate reservoir before drillingappeared in the " diarrhea" and other dangerous situations, before the tower in gas drilling canonly play straight well, prone to overlfow and blowout situations, for example in Tazhong823well blowout accident.In this paper halibut ifne pressure control drilling technology in high gas field gas ifeldTarim tower ifrst application development, drilling pore fractured carbonate reservoir, in orderto raise the level of the horizontal length and safety drilling. Detailed introduction of ifnemanaged pressure dirlling technology, process and equipment. Drilling a well pressure controlreport and analysis, elaborate stage pressure control technology of the actual level anddevelopment direction, for the next step of domestic equipment to control pressure helpful.