The lube kitchen: getting the mix right

July 24, 2024

The automotive sector relies heavily on lubricants to keep components operating smoothly. Selecting the right additives helps boost machinery efficiency and reliability.

Condition monitoring specialist company WearCheck provides predictive maintenance services to a wide range of businesses operating in the transport sector. This includes those operating fleets of buses, trucks, mining and agricultural vehicles, and many other vehicle types.

“Fully formulated lubricants have many functions and are classified into five fundamental groups: reducing friction and wear, dissipating heat from critical machine components, removing or suspending deposits, protecting metal surfaces from degradation and corrosion, and acting as a structural material,” says WearCheck technical manager, Steven Lumley.

“Lubricants serve a diverse range of applications – from car engines to water pumps to the bobbin cases of sewing machines – each requiring different combinations of base oils and additives,” she elaborates.

“Blending and formulating lubricants is complex, requiring a high degree of engineering and complex chemistry, as well as an in-depth understanding of the ingredients’ chemical qualities and how those chemicals interact,” she continues.

According to Lumley, while base oils themselves perform most of a lubricant’s functions, they can only do part of the job, and additives are needed when a lubricant’s base oil doesn’t provide all the necessary properties. “Additives improve the good properties of the base oils and minimise the bad. Typical lubricants contain a base oil, an additive package, and (optionally) a viscosity index (VI) improver. Lubricant additives are organic or inorganic compounds dissolved or suspended in oil,” she explains.

“Not all lubricants contain the same combination of additives – and certainly not in the same treat rates. Additive concentrations range from 0.1 to 30% of oil volume, depending on the application,” she says. “Turbine, hydraulic, and industrial gear lubricants demand much lower treat rates of additive packages compared to automotive gear, transmissions, and petrol and diesel engines, which are the most demanding and require the most additives.”

Lumley emphasises that different lubricant additives have different functions, while they are also chosen for their ability to mix easily with the selected base oils, their compatibility with other additives, and their cost effectiveness.

“The geometry and metallurgy of the components, operating temperatures, load, potential exposure to contaminants, combustion products, and typical drain intervals are all considered when selecting the ideal cocktail of additives,” Lumley explains. “The optimal combination of base oil and additives allows the finished lubricant to meet specified properties and performance characteristics outlined by OEMs and lubricant standards organisations.”