The Wait & Weight method is one of the well killing techniques used extensively all over the world. To explain briefly, it is a constant bottom hole pressure (BHP) method of circulating the kick out while pumping a heavier kill mud into the well to replace the original mud which was in the well when the kick occurred. This requires that a certain circulating pressure versus pump strokes schedule must be maintained while pumping the kill mud, to keep the formation pressure equally balanced to prevent additional influx into the well. This pressure schedule helps to pre-determine the amount of circulating pressure that must be maintained at the drill pipe pressure gauge at any time when the kill mud is traveling from surface to bit. The standard methodology used for calculating the pressure schedule in vertical wells, assumes a linear relationship between the circulating pressure and the volume of kill mud pumped. If the same method is used in a deviated or horizontal wells, serious problems may occur. This includes over pressuring the formation which may lead to loss circulation, more complications in well control and or loss of well and its production.

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