Casing and liner size (inches) (4 112 5 512 Bit and hole size (inches) 43/4 57/8 (618 6112 (7778 Casing and liner size (inches) 65/8 7 75/8 3/4 85/8 95% Bit and hole size (inches) 7 7/8 (8 1/2 (8314 9112 (1057) 12 1/4 Casing and liner size (inches) (857 9 5/8 9718 10 3/4 11314 (11778) 13 3/8 14 Bit and hole size (inches) (105/8 (121/4 (14 34) (171/2) Casing and liner size (inches) (1314 (1 718 13 3/8 14 16 20 Bit and hole size (inches) (14 314 (171/2) 20 26 Casing and liner size (inches) 16 20 24 30 7000 ! 8000 10000 | 1000 Formation Pressure Fracture Pressure 12000 Depth ft 13000 14000 15000 16000 17000 9 10 16 17 18 19. 11 12 13 14 15 Equivalent Mud Weight ppg c) The figure in the last page illustrates the relationship between the pore pressure gradient, fracture gradient and depth (Assume a trip margin=0.3 ppg for both pore pressure and fracture pressure). i. Select casing setting depths. (12 marks) ii. Determine equivalent mud weigh for all stages. (4 marks) iii. Determine the bit sizes and casing sizes needed for drilling to the total depth if the production strings for a certain well consist of 5 1/2 in. (6 marks) Casing and liner size (inches) (4 112 5 512 Bit and hole size (inches) 43/4 57/8 (618 6112 (7778 Casing and liner size (inches) 65/8 7 75/8 3/4 85/8 95% Bit and hole size (inches) 7 7/8 (8 1/2 (8314 9112 (1057) 12 1/4 Casing and liner size (inches) (857 9 5/8 9718 10 3/4 11314 (11778) 13 3/8 14 Bit and hole size (inches) (105/8 (121/4 (14 34) (171/2) Casing and liner size (inches) (1314 (1 718 13 3/8 14 16 20 Bit and hole size (inches) (14 314 (171/2) 20 26 Casing and liner size (inches) 16 20 24 30 7000 ! 8000 10000 | 1000 Formation Pressure Fracture Pressure 12000 Depth ft 13000 14000 15000 16000 17000 9 10 16 17 18 19. 11 12 13 14 15 Equivalent Mud Weight ppg c) The figure in the last page illustrates the relationship between the pore pressure gradient, fracture gradient and depth (Assume a trip margin=0.3 ppg for both pore pressure and fracture pressure). i. Select casing setting depths. (12 marks) ii. Determine equivalent mud weigh for all stages. (4 marks) iii. Determine the bit sizes and casing sizes needed for drilling to the total depth if the production strings for a certain well consist of 5 1/2 in. (6 marks)