Novel Engineered Fiber Based Wellbore Strengthening Material in Prevent and Control Real-Time Loss Circulation While Drilling in Bibi-Hakimeh Oil Field

Loss circulation is one of the most time and cost consuming problems which occurs mostly in naturally fractured formation, induced fractures and also may happen through highly permeable formations and can causes many operational problems such as differential pipe sticking, drill string stuck in the wellbore, drilling fluid costs due to compensate of the lost fluid via the formation, well flow, blowout and etc. controlling severe to total lost circulation in naturally/induced fractured formations has always been challenging. While solving lost circulation after occurrence is critical, prevention is the best drilling practice for saving the operator time and money. One important component of the prevention plan is the design of wellbore strengthening treatments. The goal of these treatments is to increase the “hoop stress” in the near wellbore region, widen the mud weight window and enable wellbore pressure containment. To address this problem, novel fiber based wellbore strengthening material is designed as an engineered solution to improve wellbore wall tensile and compressive strength and reduce drilling non-productive time caused by lost circulation. By using newly fiber based wellbore strengthening material in drilling fluid composition during drilling operation, loss circulation would be prevented in more than 80% of loss zone layers and in case of encountering cavernous layers with large fracture widths it makes the operator easier to control the loss. In this paper a novel fiber based wellbore strengthening material named LIGNO-SEAL is introduced and successfully used to prevent and control loss in an onshore well with severe to complete loss situations in BIBI-HAKIMEH oil field in southern parts of Iran.