API RP 13M (R2023) PDF
Recommended Practice 13M provides consistent methodology for determining the viscosity of completion fluids used in the petroleum and natural gas industries. For certain cases, methods are also provided to determine the rheological properties of a fluid.
This edition of API RP 13M is the identical national adoption of ISO 13503-1, Petroleum and natural gas industries- Completion fluids and materials-Part 1: Measurement of viscous properties of completion fluids.