The worlds thirst for API Group III base stocks should continue to grow in coming years, as requirements for light-duty automobiles keep increasing and heavy-duty vehicles become a new source of demand, an official with SK Lubricants said recently.
Emissions regulations and the push for improved fuel economy are key factors in Group III demand for both light- and heavy-duty vehicles, Nick Clague, global technical manager at SK, said during the ICIS World Base Oils & Lubricants Conference in London last month. Governments around the world are striving to reduce carbon dioxide emissions from automobiles, and the main way of doing this has been to reduce fuel consumption.
Automakers have made a wide variety of design changes to help improve fuel economy, but the main adjustment for lubricants has been to shift to lower viscosities in order to reduce friction. Thus the migration from 10W-30 and 10W-40 passenger car motor oils to 5W-30, 5W-20 and 5W-40 grades and now to 0W-30 and lighter. Lighter motor oils have required lighter base stocks, but since lighter oils tend to have more light, volatile hydrocarbons, formulators have simultaneously needed tighten down on volatility limits – something accomplished through the use of more highly refined base stocks, specifically Group III and polyalphaolefins.
Those emissions standards were first adopted in countries with developed economies – in Western and Central Europe, Japan and North America – which meant the corresponding lubrication requirements were largely limited to those markets. However, Clague noted, those standards are spreading to other parts of the world, and automakers are increasingly adopting global engine platforms. That means the Group III demand that exists in Europe and North America is or will be spreading to Southeast Asia, the Middle East and South America.
Everybodys moving to lower viscosity, everybodys moving to higher durability, everybodys moving to longer oil drains, said Clague. Were seeing a bigger emergence of more synthetic lubricants. And the specifications are going global as well now. Were seeing ACEA [European Automobile Manufacturers Association] oils available on a global basis.
Clague said Group III demand will also rise because of a number of social factors. An increased global population – up to 10 billion by 2050 with an increase in middle class population – will lead to an increased use of cars and online shopping, meaning increased demand for light-duty and heavy-duty engine oils and increased demand for high quality lubricants.
Heavy-duty engine oils will not become a growth vehicle for Group III because governments are now bringing the same fuel economy focus to that segment of the auto industry. As with passenger car motor oils, heavy-duty oils will shift to lighter grades, Clague said. Whereas 15W multigrades have dominated until now, European OEMs are changing to 10W-30 and 5W-30 for factory fill, with 0W-20 looking like a popular choice down the road. These oils are Group III formulations, he said.
The European aftermarket is moving from 15W-40 ACEA E7 standard lubes, which dont require Group III base oils, to 10W-40 and 5W-30 oils meeting the ACEA E6 and E4 specifications, which can use all or mostly Group III base stock.
In the future, its likely to be lower viscosity grades based on [high temperature high shear], said Clague. Future ACEA sequences may drive HTHS down to 2.6 or even 2.3cP, he explained.
Group III+ base oils may be needed to meet future specification needs, and high viscosity index Group III demand is growing, Clague said. Polyalphaolefins can be used to blend high-performance synthetic lubricants, especially passenger car motor oils and heavy duty motor oils.