Transparency at heart of WinGD cylinder oil guidance

WinGD published its list of validated cylinder oils in a new format in July 2020, showing oil specific usage guidelines for each product. This move has led to improved transparency for customers, clarifying oil usage recommendations and ending previous uncertainty about product specific limitations.

The revision has improved the transparency around specific oil usage restrictions as stipulated in No Objection Letters for cylinder oils. “Previously, we were at times unable to fully answer customers’ queries around specific oil usage restrictions, due to the confidential nature of NOL restrictions,” Venter noted, adding that the previous steady flow of customer queries had slowed to a trickle since the publication of the guidance.

The engine designer’s decision to adopt a more transparent approach was discussed beforehand and welcomed by oil majors and smaller lubricant suppliers as well.

“We began the process of revising the list of validated lubricating oils in late 2019. It required going through every single cylinder oil, corresponding laboratory analyses, and the conditions in which that oil was validated. It was a painstaking and sometimes arduous process,” Venter noted.

The engine designer’s decision to adopt a more transparent approach was discussed beforehand and welcomed by oil majors and smaller lubricant suppliers as well.

“We began the process of revising the list of validated lubricating oils in late 2019. It required going through every single cylinder oil, corresponding laboratory analyses, and the conditions in which that oil was validated. It was a painstaking and sometimes arduous process,” Venter noted.

Amendments to cylinder oil guidance

In addition to now openly showing oil specific limitations, the revised guidance highlighted changes in the BN15-25 ranges, and in the BN70 category, where the maximum sulphur content of fuel oil was lowered from 2.5% to 2.0%

The main consequence of amendments to usage guidance for BN15-25 cylinder oils was that these are no longer permitted for fuels with up to 0.50% S. They are only suitable for gas and liquid fuels containing <0.10% S.

“The revisions in maximum sulphur contents were based on operational experience, and in part pre-empted by the entry of IMO 2020 fuels into the market, as well as broader engine developments, which have increased the stresses on lubricating oils,” Venter commented.

The Motorship notes that an additional category, labelled as ‘DF validated’ shows whether the oil has passed a validation trial while burning gas as the predominant fuel during that trial. This does not preclude certain other oils, while validated on liquid fuels, from being used in gas mode. The newly published list clearly indicates this.

While other two-stroke engine manufacturers have also revised their lubrication oil guidance in 2020, Konrad Räss, Head Engine Technology and Development at WinGD noted that WinGD’s guidance did not differentiate between engine designs, for example older or newer ones.

“We haven’t changed our tuning strategy since I’ve been at WinGD and the previous companies (NSD, Wärtsilä). Highly efficient tunings for lowest fuel oil consumption is our standard. The appetite for BN and oil feed rate depends, among others, on the in-cylinder purity which is influenced by the tuning. Our latest design engines behaviour regarding feed rate and BN is comparable to our previous designs,” Räss said.

In fact, both Venter and Räss stressed that the revised list of validated cylinder oils did not suggest that any products were ineffective. The goal of the revision was to include previously undisclosed information, held in the NOL, to the customer.

“We are simply offering guidance, but if our customers have a product that they have been using with a certain fuel with good results, there is no problem with continuing to use it,” Räss said.

However, he noted that by closely looking at the usage recommendations of lube oil products, technical managers or ship superintendents might be able to safely lower feed rates. The Motorship notes that separating the procurement of consumables from operational considerations meant operators risked missing out on efficiency savings.

Venter concurred. “You could feed [some cylinder oils] in at feed rates of 0.60g/kWh, as opposed to pouring it in at 1.0-1.1 g/kWh, with better performance.”

Räss noted that WinGD continued to support piston underside analysis as a tool to gain insight into the performance of cylinder oils.

“We still stick to the piston underside analysis,” Räss noted, adding that this provides data on wear particles and on the usage of the BN. “This still provides the best support for our customers who want to reduce feed rates,” Räss added.

Declining sulphur levels have improved the ability of piston underside analysis to analyse lube oil performance. “The lower the sulphur in the fuel, the easier it will become in the future,” Räss added.

However, looking further ahead, WinGD is developing systems to combined real time engine performance data with real time fuel and cylinder oil data.

“The dream would be to develop a system where the customer never has to adjust the feed rate. The feed rate would be adjusted automatically by an algorithm drawing on the vessels’ previous operational data,” Räss said.

While WinGD has introduced real-time digitalisation solutions, such as its WiDE system – digital onboard monitoring system – which feeds into a database that provides real time data, incorporating cylinder oil data into this poses some challenges.

“One of the challenges is developing sensors to track different parameters of lube oil during operation. It is one thing to install a digital temperature gauge that can send data to an engine management system, but it is another to assess retrospectively the real time multiple interacting parameters of the fuel, engine performance and feed rates, and integrating this with scrape-down oil analysis,” Venter noted.

However, WinGD is continuing to work with “certain oil majors” to develop real time measurement data of cylinder oil in- or post-use to complement engine running data. “Watch this space – it is quite exciting,” Venter concluded.