- DMS = Dimethylsiloxane
- 1st character = Trimethylsiloxy-terminated
- 2nd character = viscosity in decades, i.e. 10x
- 3rd character = viscosity to 1 significant figure
|Centistokes||Poise||SSU||Zahn #1||Zahn #2||Zahn #3||Zahn #4||Zahn #5||Ford #3||Ford #4||Krebs units||SAE||Liquid example|
*measured at 2 °C (a cold winter day)
Note: The precision of conversion in this table is limited by two factors. It assumes that the density of liquids is 1 so that stokes and poises are the same and that viscosity is independent of shear rate, i.e., the fluid is Newtonian. To correct for density in converting from centistokes to centipoises, multiply specific gravity by centistokes.
Any standard viscosity grade of polydimethylsiloxane can be blended together with another viscosity grade of the same fluid to produce an intermediate viscosity. This chart provides a means for determining the proper blend ratio. The chart should be used as follows:
- Decide upon the viscosity grades to be blended. For high accuracy, measure the actual viscosity of the blending fluids.
- Locate the lower viscosity on the left hand scale. Locate the higher viscosity on the right hand scale.
- Connect these two points with a straight line.
- Locate the point where the line indicating the desired blend viscosity intersects the constructed line.
- From this point, follow down to the horizontal scale to read the percent of the higher viscosity fluid to use in the blend.
This method is reasonably accurate in predicting blend viscosity when the two fluids differ in viscosity by no more than one magnitude (one power of ten). When fluids covering a wider range are blended, the chart will only approximate the finished viscosity. To achieve a viscosity of 800 cSt as shown in the example, 68% of 1000 cSt and 32% of 500 cSt fluids are blended.