Whilst drilling the 8 1/2" hole section of a well the mud pit level indicators indicate that the well is flowing. When the well is made safe the following information is collected : Drill-pipe pressure = 100 psi Casing pressure = 110 psi Pit gain = 10 bbls Using this and the information provided in attachment 1, carry out the necessary calculations to determine: a) the formation pressure and kill mud-weight b) the type of influx c) the time to kill the well d) the time to the end of stage 1, 2, and 3 of the killing operation e) the pump pressure during stages 2, 3, and 4 of the operation.
ATTACHMENT 1 CASING/HOLE DATA 9 5/8" 53.5 lb/ft casing shoc 8 1/2" lolc 7000 ft. 9100 ft DRILLSTRING DATA: 5" 19.5 lb/ft drillpipe in hole BHA - 360 ft of 6.25" x 2 13/16" collars (capacity = .0178 bbl/ft) (capacity = .0077 bbl/ft) PUMP DATA: Type - Triplex pump kill rate/circ. press. Output = 0.1428 bbls/stk 14 spm @ 600 psi circ. pressure MUD DATA: Mud in hole 9.5ppg DEPTH OF KICK: 9100 ft. ANNULAR CAPACITIES : Collar/Hole (6.25" Collar x 8 1/2" Hole) 0.0323 bbl/ft D.P./Hole (5" Drillipe x 8 1/2" Hole) 0.0459 bbl/ft D.P./Casing (5" Drillpipe x 9 5/8" Casing) 0.0465 bbl/ft