MAN launches flagship four-stroke
The 12-cylinder vee-line MAN 45/60CR will be among the first to be launched in 2020
A new four-stroke engine from MAN Diesel & Turbo reveals the engineer’s belief in the future of the cruise market. And contrary to some predictions, MAN believes the sector will continue to be driven by diesel. Gavin Lipsith reports.
Until last month, it was nearly ten years since MAN Diesel & Turbo had launched a new four-stroke engine. The Copenhagen-based company clearly does not take such launches lightly, which makes the new 45/60CR medium-speed engine – an eventual replacement for the stalwart 48/60CR and due in service from 2020 - an important update to the more powerful side of MAN’s four-stroke portfolio.
The rationales given for the new 450mm bore engine run long: with 1,300Kw of output per cylinder, an rpm of 600 and a specific fuel oil consumption of around 166g/kWh – all significant upgrades versus the 48/60CR – the need for modern performance standards was clearly a key reason.
Alexander Koerber, product development manager, told guests at a recent press launch at its four-stroke engine factory in Augsburg: “We are extending the family, and of course when you add another member to any family you need to think carefully before doing it.”
Part of that thinking was how to deploy up-to-date engine technology to improve efficiency, power density and – crucial for the passenger vessels which form a key target sector for the new engine – noise and vibration levels. To that end, key features include two-stage turbocharging, updated common rail technology and variable valve timing (to make full use of the efficiency gains from the turbocharger) and a new version of MAN’s mapping software ECOMAP that optimises injection characteristics depending on engine load.
The mapping software is deployed via an automation system – MAN’s safety and controls or SaCoS system – that has itself been modernised. SaCoS 5000 uses compact modules integrated into the engine, rather than one big unit with multiple access points. The result is a decentralised automation system that requires less cabling (due to shorter cable routes) and is easier to upgrade by simply adding new modules. ‘Plug-and-play’ functionality, particularly the automatic detection of new modules, make maintenance, retrofitting and upgrading a much simpler task.
There are other reasons too for shipyards to welcome this evolution in MAN’s four-stroke design ethos. After discussion with its customers MAN worked on simplifying the interfaces between the engine and the ship. This is evident particularly in the addition of a front auxiliary box (FAB) containing lubrication treatment (cooling and purification) that would previously been part of the separate engine room plant. Similarly, the engine turning gear – enabling engineers to manoeuvre engine components for servicing – is also integrated to the side of the engine instead of on a separate skid. This means yards have less to worry about when it comes to designing and laying out engine rooms, reducing the space needed and the complexity of the build.
The power density of the engine is also intended to simplify installation and enable a smaller engine room. Although the 12V version comes in at seven tonnes heavier than the comparable 48/60CR, it offers a further 1.2MW of power output and, at 166g/kWh, a 4% decrease in specific fuel oil consumption. Koerber notes that the extra weight is due to reinforcing the engine base and the addition of the two-stage turbocharger as well as extras like the FAB.
All this contributes to what MAN believes is an attractive lifecycle cost offer. Sokrates Tolgos, head of sales, cruise and ferry, MAN Diesel & Turbo notes that cruise operators are more likely than tanker owners, for example, to pay more for an efficient engine as they pay for the fuel themselves.
MAN claims that, based on a representative load-profile of a cruise vessel, a ship operating with a 45/60CR engine would enjoy a fuel-oil cost benefit of 5-12% in comparison with a vessel powered by an equivalent engine from other manufacturers. For a cruise vessel of around 120,000-150,000gt, with 60-65MW of installed power (and an assumed fuel price of €500/tonne), this translates into annual savings of €0.9-2.4 million.
Tolgos says: “The focus is mainly on the cruise sector, which is why it makes sense for us to launch now: most of the cruise yards are full and we are already talking with companies about projects that will be delivered in 2021 and 2022.”
He anticipates that, driven by growth in Asian interest, the cruise building boom will continue unabated for at least ten years. The company already claims to have benefited more than other engine makers from accelerating cruise building – saying it has gained significant market share in recent years – and hopes the MAN45/60CR will drive that trend further.
The 12V and 14V versions - boasting power outputs of 15,600kW and 18,200kW respectively - will be launched first, towards the end of 2020. The in-line range will be introduced later, in 2022. The engine is intended to be the start of a new family, and other variants including a dual-fuel LNG engine will be launched at a later stage.
It may seem surprising that MAN is not putting more development emphasis on the dual-fuel version, given a spate of cruise newbuildings contracted over the last 18 months to be powered by gas. But Tolgos notes that MAN’s growth in the sector has come purely from liquid fuel engines, and he notes the company’s conviction that cruiseships will be predominantly driven by diesel until at least 2030.