The main technical indexes of fuel oil are "viscosity, sulfur content, flash point, moisture, ash and mechanical impurities". Viscosity: Viscosity is the most important performance index of fuel oil. At present, 40℃ kinematic viscosity (distillate fuel oil) and 100℃ kinematic viscosity (residual fuel oil) are commonly used in China. In the past, China's fuel oil industry standards used Engler viscosity (80℃, 100℃) as the quality control index, and classified brands by kinematic viscosity at 80℃. The kinematic viscosity of oil is the ratio of dynamic viscosity to density of oil. The unit of kinematic viscosity is Stokes, or Stokes for short. When the kinematic viscosity of the fluid is 1 poise and the density is 1g/ cm3, the kinematic viscosity is 1 stokes. CST is the abbreviation of Centistokes, which means Liz, that is, 1 stokes 1%.

Sulfur content: too high sulfur content in fuel oil will cause corrosion of metal equipment and environmental pollution. According to the sulfur content, fuel oil can be divided into high sulfur, medium sulfur and low sulfur fuel oil.

Flash point: it is an index related to the safety of use. If the flash point is too low, it will bring fire hazards.

Moisture.

Ash.

Mechanical impurities. Mechanical impurities will block the filter screen, resulting in oil pump wear and nozzle blockage, affecting normal combustion.