#Low viscosity oil meaning iso#

Choosing the right viscosity for your application will: Oil separates two metal surfaces and allows them to glide against each other rather than grinding and wearing down the material. Oil viscosity will impact how vehicles, equipment and other machines perform. High-viscosity oil is more robust and thick - like honey or molasses - making it ideal for industrial, heavy-duty machinery which operates at higher temperatures. Thinner oil has a lower viscosity, similar to water, pouring more effectively and allowing the engine to start much faster in colder weather. This behavior contributes to the oil’s ability to flow through the engine. Specifically, motor oil will thin out as the temperature increases and thicken as it cools. Insufficient fuel index margin (resulting in limitation in acceleration and load).Viscosity is the consistency of a liquid before and after internal friction is applied. Insufficient injection pressure (resulting in difficulties during start and low-load operation), andģ. Breakdown of hydrodynamic oil film (resulting in seizures),Ģ. So a very low-viscosity fuel oil challenges the function of the pump in three ways:ġ. Reason is that with a too low viscosity a satisfactory hydrodynamic oil film between fuel pump plunger and barrel cannot be maintained, thereby causing the risk of fuel pump seizures and/or sticking. What is often overlooked but what is recognized to be more critical for marine fuel system and diesel engine fuel pumps is when the viscosity will be less than 2 cSt. For the marine industry, some engine manufacturers recommend testing for lubricity to be carried out only if sulphur is below 0.01% m/m. The main reason behind poor lubricity is that the removal of sulphur during the refinery process also impacts (reduce) the lubricity capacity of a fuel.įor marine, the impact is significantly less as marine fuels still contain sulphur and thereby normally maintains its lubricity capacity. The lubricity criterion was adopted from the automotive industry, where a variety of fuel pumps and fuel injection systems were damaged by low sulphur fuels with poor lubricity.

#Low viscosity oil meaning iso#

Lubricity was introduced as an ISO 8217 specification parameter with the release of the 2010 edition. ISO 8217 includes lubricity for clear and bright distillate fuels only when sulphur is below 0.05 % m/m. It is known that lubricity is not a critical parameter and only applicable to ultra-low sulphur distillate fuels e.g.

The misconception is that lower viscosity fuels might be more susceptible to lubricity issues. Lubricity is the measure of the reduction of friction of a product.

Easier to perform onboard fuel treatment (Stokes law) Requiring lower fuel temperatures so less thermal stress Therefore, low viscosity and low density fuel products are generally an indication of a better quality product. These different blending components have inherently lower viscosity and density properties resulting in a lower density and viscosity product but with a higher overall quality. Instead, lighter blending components are being used such as higher quality refinery streams and even distillate fuels. To produce 0.50% fuels, it is no longer possible to use large quantities of low quality and heavy residual streams in the blend. With the introduction of the global Sulphur cap of 0.50%, density and viscosity were no longer the main blending targets, but instead it was replaced by sulphur as the main blending target. Viscosity was also a key blending target for refineries and fuel suppliers where blending was usually done using a low-quality, heavy residual stream (e.g cycling oils containing considerable amounts of highly abrasive cat fines). Historically, viscosity was used to order a fuel by indicating the grade based on the viscosity of the product. In reality, viscosity only becomes a serious quality concern when the viscosity is below 2 cSt. Viscosity is not an indication of fuel quality, and it is a misunderstanding that residual fuels with a lower viscosity automatically means that the product is lower in quality. It is used for the calculation of CCAI (the index of the ignition quality of residual fuel oil) It defines the heating temperatures for storage, transfer, fuel treatment and injection It is used as an indicator of the grade The significance of viscosity for marine fuels is such that The viscosity of a fuel decreases when the fuel temperature increases i.e.

Viscosity is defined as the resistance of a fuel to flow and is a measure of the fluidity of the product at a certain temperature.