Q1. While drilling a vertical well at a depth of 9,000 ft with 13 ppg mud. Gas cut mud was observed at shale shaker. Tool Pusher decided for bottoms–up monitoring of out coming mud. They recorded average mud weight of:
12.5 ppg for 0 to 900 ft
12.8 ppg mud for 900 ft to 1500 ft
13.0 ppg mud for 1500 ft to 9000 ft.
Due to the gas cut mud, how much was the reduction in bottom hole pressure?
a. 15 psi
b. 25 psi
c. 30 psi
d. 60 psi
Q2. Is it true that the original drilling fluid density will be sufficient to control the formation pressure once stripped back to bottom if a kick has been taken off bottom due to swabbing?
Q3. It was decided to reduce the mud weight from 12.4 ppg while tripping in the well of 9,880 ft TVD. String was run to 5,950 ft and original mud was displaced by 10.8 ppg mud.
(i). What will be the bottom hole pressure now?
a. 6043 psi
b. 5548 psi
c. 6370 psi
d. 5875 psi
(ii). When string was run down to bottom the entire well was displaced by 10.8 ppg mud. Calculate the bottom hole pressure in static condition.
Q4. What is the definition of MAASP?
a. The total pressure applied at casing shoe that can cause losses at shoe.
b. The surface casing pressure that in addition to hydrostatic pressure is likely to cause losses at the shoe formation if exceeded.
c. The maximum pressure allowed on the casing gauge during a kill operation.
d. The maximum pressure allowed on the drill pipe gauge during a kill operation.
e. The maximum bottom hole pressure allowed during a kill operation.
Q5. While drilling, the mud weight was increased from 12 ppg to 13.5 ppg expecting higher formation pressure below. How this increase of mud weight will affect MAASP (the casing shoe is at 4697ft/5500 ft)?
a. Increase by 366 psi
b. Decrease by 366 psi
c. Increase by 429 psi
d. Decrease by 429 psi
Q6. Which of the following are important for the calculation of formation strength at the shoe? (Select three answers)
a. Accurate pump strokes counter.
b. Accurate pressure gauge.
c. Exact mud density.
d. Exact vertical depth of casing shoe.
e. Accurate hole capacity.
f. The pressure limit for the pump.
g. Exact measured depth of the casing shoe.
Q7. Select three parameters that influence the MAASP?
a. The fracture pressure of the formation at casing shoe.
b. The dia of last casing string.
c. The pump rate when performing the formation strength test.
d. The density of the drilling fluid.
e. The maximum allowable pump pressure.
f. The casing shoe depth of the last casing string.
Q8. After lowering casing, which of the following operations are to be taken care of prior to conducting a leak —off test. (Select two answers)
a. Drill casing shoe and about 10 ft in to new formation.
b. Keep the bit close to bottom.
c. Circulate and condition the mud to get uniform column of mud in the well.
d. Line up pump to conduct leak off at slow circulating rate.
Q9. What is normal formation pressure normally assumed to be?
a. 0.433 psi/ft.
b. 1 psi/ft
c. 0.465 psi/ft
d. 0.5 psi/ft.
Q10. A casing is set at a depth of 7260 ft and true vertical depth of casing shoe is 6298 ft. After drilling shoe and new formation, leak off test was conducted with 11.2 ppg mud. It was found that the formation strength is 5400 psi.
Find out the maximum allowable annular surface pressure (MAASP).
a. 1171 psi
b. 5400 psi
c. 3668 psi
d. 1732 psi