dc.description.abstract | Exploration of oil and gas have to be proven through drilling operation. In drilling operation, there is a barrier between formation and drilling equipment which called drilling fluid. Designing drilling fluid properly is necessary to raise a successful drilling operation. A difficulty of drilling fluid design depends on formation lithology characteristics and drilling requirements. Oil-based mud and water-based mud are commonly base mud that used to drilling fluid system. Shale stability is the most often problem which encountered during drilling operation. According to comparison between oil-based muds and water-based muds, drilling fluid with oil as the base mud has better shale inhibition than water as the base mud. Even oil-based muds are the best inhibitor, cost and environmental regulations would be a major concern in selecting oil as the base mud. It causes companies those provide a service of drilling fluid have been developed technology that improved water-based mud to perform as well as oil-based mud. It is called High-Performance Water-Based Mud (HPWBM). HPWBM designed to gives good inhibition for reactive shale through chemical bonding. Therefore, it is not like other conventional cation inhibiting in a way of cation exchange capacity. | en_US |