Chloride Test Drilling Mud Procedures
The water-based fluid may contain chlorides from the base fluid (e.g. Sodium or Potassium Chloride), or may pick up chlorides while drilling. Chloride Test Drilling Mud is useful for determining any unexplained changes in water-based mud salinity, because an increase or reduction in salinity will indicate salt or water contamination. So It is important to have chlorides in drilling mud.
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