What is the difference between mineral, semi-synthetic and synthetic oils?
When choosing engine oils for your aircraft, we are often faced with this dilemma – the choice between mineral, semi-synthetic and synthetic oils. What then is the actual difference between mineral and synthetic oils? Mineral oils are refined petroleum oilsblended with very small amounts of additives such as pour point depressants and anti-oxidants. Whereas, synthetic oils are mineral oils that have been chemically engineered to improve its lubricating properties. Because of a higher quality oil, synthetic oils are usually more expensive. A semi-synthetic oil is then a balanced blend of both the mineral and synthetic oils.
How does this affect my aircraft engine? Which engine oil is better for my aircraft?
As aircraft fuels are currently leaded, the mineral oils are important in helping disperse lead by-products, which could build up in your engine to form ‘sludge’. Mineral oils are thus generally used as ‘break-in’ engine oils. The downside of a pure mineral oil-based lubricant is that it degrades and form deposits (Coke) at high temperatures such as those generated by your turbine engines. These deposits result in coking of aircraft engines, resulting in higher engine maintenance and repair costs. In worst-case scenarios, it could even lead to bearing failures and engine fires.
Synthetic oils are thus chemically engineered to be a more efficient lubricant and have better additives absorption capabilities. This means that more additives such as corrosion inhibitors, anti-wear additives and detergents are better absorbed in the Synthetic oils, which then results in better protection against wear and corrosion.
Since the aviation industry still requires leaded fuels, a careful blend of mineral and synthetic oil was created to balance between dispersing lead by-products and having more additive absorption capabilities. With better additive absorption capabilities, your aircraft engine receives outstanding corrosion and wear protection, leading to sparkling clean engines. Another benefit of the blend of mineral and synthetic oil is a more thermally stable oil that deteriorates slower. What this means for aircraft owners is that a more thermally stable oil could lead to a reduction of fuel and oil consumption.
Petroleum Logistics is proud to carry the Aeroshell W 15W-50 piston engine oil that was innovatively created with semi-synthetic fuels for cleaner engines and fuel and oil savings.