Oil Fuels - Viscosities vs. Temperatures

Saybolt Universal Seconds - SSU - kinematic viscosity versus temperature for typical fuel oils:

• T_F = T_C 9 / 5 + 32
• viscosity converting chart
• SSU (Saybolt Universal Seconds) = centiStokes (cSt) x 4.55 ¹⁾
  
• 4 - 5000 SSU is the maximum practical limit for pumping
• 150 - 300 SSU is the atomization range fuel oil no. 5 and 6

¹⁾ Note that this equation is correct only for a range of viscosities. There is no linear relationship between the units. Check ASTM D2161 "Standard Practice for Conversion of Kinematic Viscosity to Saybolt Universal Viscosity or to Saybolt Furol Viscosity" for more accurate methods.