Dealing with the Challenges of Underbalanced Drilling Implementation in Parsi Oilfield

摘要

Underbalanced drilling(UBD) is defined as a drilling operation in which circulating drilling fluid pressure is maintained to be lower than reservoir pore pressure.Underbalanced drilling may improve drilling efficiency and enhance well productivity. Approximately 90%of the discovered fields in Iran are in carbonate reservoirs putting Iran as one of the largest carbonate producers in the world.Under-