Blend Formula Pdf For Free

Viscosity index (VI) is a commonly used method of measuring a fluid's change of viscosity in relation to temperature. The higher the VI, the smaller the relative change in viscosity with temperature.

Viscosity blending is perhaps the most common operation in lubricant manufacture. All blenders rely upon their viscosity-blending calculators, often used as a magic black-box giving the right blend composition [1,2].

On this page you will find several calculators to calculate viscosity index or viscosity depending on the temperature. You can also find a tool to interpolate the viscosity of lubricants based on the given viscosities at 2 temperatures.

Viscosity is a measure of a fluid's resistance to flow. The SI unit of viscosity is poiseiulle (PI). Its other units are newton-second per square metre (N s m-2) or pascal-second (Pa s.)

The viscosity is typically reported in centistokes (cSt), equivalent to mm2/s in SI units, and is calculated from the time it takes oil to flow from the starting point to the stopping point using a calibration constant supplied for each tube.

Viscosity indexes, which can be found on most product data sheets, typically range from 90 to 160, but can exceed 400 and be as low as -60. The viscosity index can also give insight into the type of base oil and its quality. More refined mineral oils and synthetics will have higher VIs than lower quality base oils.

The viscosity index formula is VI=(L-U)/(L-H)x100 where L is a fluid with a viscosity of zero at 100 degrees Celsius, U is a fluid with an unknown viscosity, and H is a fluid that is 100 at 100 degrees Celsius.

The first step is to calculate the Viscosity Blending Index (VBI) of each component of the liquid blend using the following equation: (1) VBN = 14.534 × ln[ln(v + 0.8)] + 10.975. where v is the viscosity in square millimeters per second (mm²/s) or centistokes (cSt) and ln is the natural logarithm (loge).