Analysis and Understanding of Complex Situations in Pinghu BA6S Well

Well BA6S is a sidetracked well from well BA6 with φ339.7 mm casing, and the main purpose is to tap the potential of gas reservoir and to explore the low porosity and low permeability formation beneath P8 in Fang Ⅱ fault block. There occured 18 drill strings washout and 1 gas kick while drilling this well. In this paper, the complex situations in this well are analyzed, including well trajectory, sidetrack plan, drill string fatigue, critical surface RPM and overflow prediction in low porosity and low permeability formation, and some suggestions have been made.This can provide valuable reference for future similar drilling plan and feld operations.