Chevron Marine Lubricant’s low sulphated ash trunk piston engine oil Chevron HDAX 9700 has become the first lubricant to gain time-unrestricted approval for use with MAN Energy Solutions’ four-stroke engines running on either LNG or distillate fuels (with a sulphur content of up to 0.10%).

This approval is the first of its kind and offers simplicity for operators switching between the two fuels, meaning that they can use just one lubricant, rather than having to change lubricants after a fixed period operating on one fuel or the other. Other lubricants go through validation testing on engines running either gas or distillate fuels and are granted limited approval for the other fuel. Chevron HDAX 9700 secured its unrestricted dual approval due to its unique development.

Chevron HDAX 9700 was tested on Luxembourg dredging and offshore operator Jan De Nul Group’s trailing suction hopper dredger and ultra-low emission vessel Sanderus. The company required an engine oil with very low sulphated ash formation due to the use of a variety of low sulphur fuels (below 0.10% sulphur) with selective catalytic reduction (SCR) and diesel particulate filter (DPF), as part of its strategy to comply with European Stage V limits on nitrous oxides (NOx) and particulate matter (PM) emissions from ships.

Michel Deruyck of Jan De Nul explained: “We needed a low sulphated ash oil because the DPF would not handle high levels of ash deposits. But MAN ES had not approved any low sulphated ash oils for use with distillate fuels. We had already worked with Chevron for low sulphated ash oils on three other vessels, so we extended the relationship and ran a validation test for HDAX 9700 on Sanderus.”

Chevron HDAX 9700 is an SAE 40 engine oil that is designed to control sulphated ash accumulation in combustion chambers and exhaust system, while providing sufficient alkalinity to protect against acidic corrosion. After 6,500 running hours, the approval for unrestricted use with distillate fuels was granted, making Chevron HDAX 9700 the first low sulphated ash oil to receive such an approval. Because low sulphated ash oils are commonly used with gas engines – which are also sensitive to sulphated ash deposits – MAN ES was also able to grant unlimited approval for the lubricant to be used when operating with LNG.

Luc Verbeeke, Senior Engineer, Chevron Marine Lubricants, said: “Our exceptional partnership with Jan De Nul Group has resulted in a valuable step forward for ship operators using either LNG or distillate fuels. The ability to use single engine oil for four-stroke engine operations will simplify operations and once more highlights Chevron’s role at the forefront of protecting marine engine condition.”

Unrestricted operation on a single lubricant will benefit operators in several sectors. Jan De Nul will use the lubricant on further dredgers as well as jack-up vessels used in windfarm construction. Any vessels looking to comply with emission control areas – or port emission limits – by using either LNG or distillate fuels with aftertreatment will also be able to use Chevron HDAX 9700.