Polyacrylamide (PAM) used in oil extraction is usually measured by Brookfield viscosity instead of Markov viscosity.

Brookfield viscosity is a commonly used method of measuring the viscosity of liquids and is particularly suitable for low shear rates of liquids. It determines viscosity by measuring the time it takes a liquid to flow through a standard pipe per unit time. Brookfield viscosity is the flow behavior of a liquid under applied shear stress over a short period of time.

In oil extraction, PAM is often used as a thickener and waterproofing agent to increase the viscosity of water injection liquid and improve the water displacement effect. By adjusting the Brookfield viscosity of PAM, flow and viscosity characteristics can be controlled to meet the needs of a specific oil field.

Markov viscosity is relatively rarely used in oil recovery applications because Brookfield viscosity better reflects the rheological properties of liquids under low shear conditions than the flow properties at high shear rates. Therefore, in oil extraction, Brookfield viscosity is often used as a reference index for evaluating and selecting PAM.

Please note that different applications may have different requirements and it is recommended to refer to relevant industry standards and manufacturer recommendations in specific cases to determine the most suitable viscosity indicators and methods. 👍😊