Oil Based Mud
Definition - What does Oil Based Mud mean?
Oil Based Mud is an oilfield emulsion which is used as a drilling fluid while performing drilling operations. In this type of oilfield emulsion, oil is present as a continuous phase (or in large amount) and water is present in the dispersed phase in low amounts of approximately 2% to 5%. It is also referred to as drilling mud or drilling fluid.
Petropedia explains Oil Based Mud
There are two types of oilfield emulsions that are used as drilling fluids during drilling operations. They are:
- Oil based mud, also called as “Invert-Emulsion Oil Mud or Water in Oil Emulsion” and
- Water based mud, also called as “Oil Emulsion Mud or Oil in Water Emulsion”.
Oil based mud has more advantages over water based mud such as increased borehole stability, prevention of hydration & dispersion of clays, high lubricity that reduces torque, drag and improved drilling conditions. Some of its disadvantages are that it is expensive than water based mud and has environmental problems.Though oil based mud is more expensive than water based mud, the overall benefits during drilling operations compared to water based mud is far more valuable than the cost.