#TITLE_ALTERNATIVE#

• Main Author: RICO NOVRIANTO (NIM : 12212094), ARNOLD
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/25816
• Institution: Institut Teknologi Bandung

Casing while drilling (CWD) is drilling technology where casing is used to substitute the drillpipe that can be set when target depth is reached and/or when there is a drilling problem such as stuck pipe. CWD operation shows good performance as it can make a gauge well, better in borehole stability, reduce loss circulation, and tripping processes are not needed. (Marbun, 2014). However, CWD has challenge that the annulus are smaller than using drillpipe, hence dynamic equivalent circulating density (ECD) is harder to be controlled. In order to calculate ECD, annular pressure loss calculation is needed during the drilling process. Annular pressure loss in CWD generally still using conventional drilling operation approximation, which this make the result will not be accurate. <br /> <br /> This study focus to CWD level III, where CWD is designed for directional drilling and retrieving Bottom Hole Assembly (BHA) back to the surface (Radwan, 2011). In this study, improvement for annular pressure loss calculation is done as the function of the drilling fluid rheology and casing and also the BHA that is used. ECD is calculated and improvement is done to the annular pressure loss calculation to get more accurate for the ECD. Improvement annular pressure loss calculation is verified by using Field X data. The result of the study shows that ECD that is calculated using improvement annular pressure loss calculation is more accurate. Therefore, optimization for CWD level III in Field X can be done when it is designed and applicated for further usage.