Mixing Viscosities Calculator: To predict blend viscosity of two or more base oils or to predict mixing ratio of base oils to reach the desired viscosity. For best results, blend base fluids from a base stock slate or fluids from the same manufacturer. See API Base Oil Interchangeability Guidelines.

Mixing Viscosities: Oil Viscosity Calculators for the blend of 2-4 base oils.

Module #1: Oil Viscosity Calculator to predict blend (mixing) viscosity of two base oils.

Base Oils Blend Viscosity Calculator

Viscosity Calculator #1

 

To predict the mixing viscosity (blend) of two liquids or base oils:
1- Enter viscosity of the first base oil
2- Enter viscosity of the second base oil
3- Fill in the percentage (%) of the first oil in the blend.
3- Select the temperature for the viscosity measurements. Viscosity measurements must be at the same temperature for both oils.
4- Click Calculate button to predict the mixing viscosity of the two oil blends at the selected temperature.

Module #2: Calculator to predict mixing ratio to reach desired oil viscosity.

Viscosity Calculator #2


 

To get a percentage of each oil to reach a target viscosity by mixing or blending two base oils:
1- Fill viscosity of the first oil
2- Fill viscosity of the second oil.
3- Fill in the desired viscosity. Desired viscosity must be between the viscosity of first and second base oils.
4- Select the temperature for the viscosity measurements. Viscosity measurements must be at the same temperature for both oils
5- Click Calculate button to predict the mixing ratio of each base oil to reach the desired viscosity.

Module #3: Mixing viscosities calculator to blend or mix more than two base fluids.

Viscosity Calculator #3

Viscosity (cSt) Wt %

 

1- Fill the viscosity of Base oil #1 and weight percent (Wt%) in the third (Wt%) column.
2- Fill in the viscosity of Base Oil #2 and weight percent (Wt%) in the next column.
3- Fill in the weight percent (Wt%) and Base oil #3 viscosity in the 3rd row. If you don’t want to include 3rd and 4th base oils, fill any value (>1) in the viscosity cell and zero (0) in the Wt%.
4- Repeat the same for Base Oil #4 by filling in the viscosity and Wt% of the Base oil.
5- Click Calculate to predict the mixing viscosity of the blend.
Please note: Leave the default value of “1” in the viscosity field if blending less than two liquids. Fill in zero 0 (or leave default “0”) in Wt % if not included in the blending calculations.
6- The Sum of Wt% must be 100.

Viscosity temperature is not required but must be the same for all base oils viscosities.
You can use this calculator to predict mixing viscosities of 2-4 base oils. Fill in zero (0) in the weight percent column (Wt%) if Base oil #3 and-or Base oil #4 are not part of the mixing viscosities.

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8 Responses

  1. Dear team,
    What’s the basis of % of base oils formulated to give the right consistency?
    Is the % fixed?

    For example, how do we know to formulate hydraulic oils 46 mineral, like how to know the exact % of base oils required to meet the VG.

    Best regards,

    1. It is easy, Just enter the base oils viscosity in the calculator:
      For example:
      Viscosity of SN500 base oil @ 40°C is: 90cSt
      Viscosity of SN150 base @40°C is: 30cSt
      Desired viscosity is: 46cSt at 40°C
      Enter above data into Viscosity Calculator #2 and the result is:
      SN500 40.93%
      SN150 59.07%
      Please note base oils viscosity can be different. Make sure to enter exact viscosity of the base oils.

  2. Your lab results are wrong. Mixing SN150 (5.13 cSt) and SN500 (10.9 cSt) will produce <9cSt viscosity. Mixing 10% of high viscosity oil (220+190 cSt) into this, will not bring 18 cSt. You are trying to make 20W-50 oil I guess. We use 10-12% of polymeric thickener or viscosity index improver with viscosity of 1500 cSt to reach 18cSt.

    You have to add 10-12% or more viscosity index improver with viscosity of 1500 cST or higher to reach 18 cST. Check your lab results.

    1. Yes U r right, we were making 20w 50. Usually we used SN 150 & 10% VI improver polymer to Make liquid VI improver, and my boss told me that liquid VI improver vis @100 is approx 220 cst. And 190 cst is the additive viscosity. Based on this we made…
      Oil 1 Vis @100: 5.13 with 23 %
      Oil 2 Vis @100: 10.9 with 67%
      Oil 3 Vis @100: 220 with 8%
      Oil 4 Vis @100: 190 with 2%
      Lab result was 18 cst @100.

  3. Used Calculator 3# My input was
    Oil 1 Vis @100: 5.13 with 23 %
    Oil 2 Vis @100: 10.9 with 67%
    Oil 3 Vis @100: 220 with 8%
    Oil 4 Vis @100: 190 with 2%

    As per calculator it was 10.9 cst @ 100. But practically it comes in laboratory 18 cst @100.

    Please help me out

  4. Great Calculation. Will be more helpful if I get the calculation for CALCLATOR # 3, in excel sheet. Thanks

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