Drilling hydraulics simulation for CBHP MPD to overcome narrow drilling window challenges.

One of the challenges in deep water well is a narrow drilling window. In some cases, drilling a well with a narrow drilling window is impossible using conventional drilling methods. Usually, Managed Pressure Drilling (MPD) method is applied to overcome this problem. The MPD sub-method used for handling narrow drilling windows is Constant Bottom Hole Pressure (CBHP) by constantly controlling the bottom hole pressure using surface back pressure. Hence, hydraulic simulation is critical in Managed Pressure Drilling (MPD). This paper presents the hydraulic design process to determine the optimum hydraulic parameter for CBHP-MPD operation. The hydraulic simulation was conducted using Landmark Software by Halliburton. The result shows that the narrow drilling window well can be drilled safely using a minimum flow rate of 200 gpm with 105 psi surface backpressure and a maximum flow rate of 305 gpm with no back pressure (generating 16.46 ppg ECD) and 500 psi back pressure while pumps off (generating 16.41 ppg). [ABSTRACT FROM AUTHOR]