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The relationship between centipoise (cP) and millipascal-second (mPa·s) is not a direct conversion of 1:1. While both units measure dynamic viscosity, they are not equivalent. The viscosity of a fluid can be measured in various units, and the conversion between these units depends on the specific conditions and rheological properties of the fluid.

The formula for converting between centipoise and millipascal-second is as follows:
1cP=1mPa\cdotps

This conversion is true for water at a temperature of 20 degrees Celsius. However, the relationship may not be the same for other fluids or under different testing conditions.

It's important to note that the dynamic viscosity of a fluid can change with temperature, pressure, and shear rate. Therefore, you cannot assume a direct equivalence between the results obtained using different testing methods or under different conditions. If you are comparing viscosity results obtained from different methods or instruments, it's crucial to consider the specific conditions and properties of the fluid being tested.

In your case, running a sample using the Brookfield Vis method at -35 degrees Celsius and obtaining a viscosity result in centipoise does not necessarily mean that you will get the same result in millipascal-second when running the same sample using the CCS (Cold Cranking Simulator) method at the same temperature. The conversion factor between cP and mPa·s may not be exactly 1:1 under those conditions, and you should refer to the specific instrument's documentation and calibration for accurate conversions.

Brookfield Viscometer (Brookfield Vis) measurements often correlate with Cold Cranking Simulator (CCS) results in assessing the viscosity of lubricants at low temperatures. sling billing problems Both methods evaluate how fluids behave under stress, with Brookfield focusing on shear rate and CCS on simulating engine starting conditions, providing complementary insights for oil performance.

Last edited by beverlywilliam10

When using the Brookfield Viscometer method, you typically measure viscosity in centipoise (cp). If you run Sample A at -35 °C and get a viscosity reading of X cp, it’s important to note that this reading reflects the fluid's resistance to flow at that specific temperature.

Now, regarding your assumption about running a Controlled Shear Rate (CSR) test (often referred to as CCS) at the same temperature: while both methods can measure viscosity, the results might not directly translate one-to-one. The equivalence you mentioned—1 cp being equal to 1 mPa·s—holds true under certain conditions, specifically when dealing with low-shear Newtonian fluids. However, if your sample exhibits non-Newtonian behavior (which many do), the viscosity measured under shear conditions may differ significantly due to factors like shear rate and sample structure.

In short, if Sample A is non-Newtonian, you might not receive back X mPa·s when running CCS at -35 °C. It's always best to consider the specific characteristics of your sample and possibly run a few tests to confirm any assumptions.

Miss Lo
Parramatta Painters

I totally get your thinking here! I’ve seen similar correlations between Brookfield viscosity and CCS results. If you run Sample A at -35°C and get X cp, you might expect to see X mpa-s with CCS under the same conditions since that table suggests a 1:1 relationship. But I’ve found that factors like the sample composition and any additives can sometimes throw a wrench in the works, so it’s a good idea to confirm with your specific tests.

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