Tugowners invest in new tug designs and environmental technology for manoeuvring ever-larger container ships while vessel masters need weather routeing to avoid devastating ocean conditions
Owners of terminal and escort tugs are investing in new technologies to tackle the combination of giant-sized container ships being brought into service and stricter environmental regulations on emissions being introduced.
Ports worldwide are expanding their facilities to accommodate ultra-large container ships (ULCSs) as these are delivered from Asian shipyards. Therefore, companies that provide marine services in these ports, particularly ship escort and berthing, needed to expand their capacities.
Power and bollard pull need to be increased without affecting the tug's stability and safety. Different fuels or propulsion technology is also being installed to comply with tighter environmental rules.
However tug capacity is enhanced in these ports, container ship captains, crew and operators need to be confident it will be more than adequate to handle their vessels when they arrive at the terminal.
One tug owner has invested in a radically different design and technology to improve performance and stability.
Novatug worked with naval architect Robert Allan and Voith to design and build the revolutionary Carrousel RAVE tug (CRT), which incorporate a safer towage system, combining two Voith in-line propellers and a Machinefabriek Luyt-built rotating winch on a carrousel for dynamic towage.
Multratug 32 and Multratug 33 came into service in Q1 and Q2 in 2018 with a towing system that revolves around the wheelhouse, minimising the risk of tugs becoming unstable, said Novatug managing director Julian Oggel. “Capsizing should be impossible when towing with the carrousel system,” he said. “This allows for the safe execution of manoeuvres that would be a higher risk with traditional tugs.”
Both Bureau Veritas-classed, 32-m tugs have around 77 tonnes of bollard pull that come from two ABC 12VDZC engines driving two Voith 32RV5 EC/250 propellers. They enable the towline force to be controlled safely from the wheelhouse.
Mr Oggel told Container Shipping & Trade that these tugs have provided escort and towage in the ports of Antwerp, Rotterdam and Bremerhaven, while being operated by Multraship and Fairplay. Since July 2018, they have both been stationed in Antwerp.
In that port “the unique manoeuvres which the CRT is capable of performing have been particularly evident when helping ULCSs that traditionally challenge the available room in the port,” said Mr Oggel. He specified the ability that CRTs have to “act as a spring when attached forward” of a container ship and their ability of braking and steering the tow.
“Conventional tugs have a hard time assisting these ships at the speed required to negotiate the bends and fairways in the port,” he continued. “Our CRT has proved invaluable in assisting these very large ships.”
“Our Carrousel RAVE tug has proved invaluable in assisting these very large ships”
These specific abilities have been recognised by tug owners as Mr Oggel said there had been firm enquiries and negotiations for more newbuildings. “Current indications are that at least six more CRTs will be ordered over the next 12 months.” Novatug is developing smaller CRT designs for other types of harbour towage tug requirements over the next five years.
For Multraship managing director Leendert Muller, investment in CRTs and other high-performance tugs is essential for maintaining capabilities and safety of tug operations in container ship ports, such as Antwerp. Multraship operates a diversified fleet of tugs of varying types, capacities and configurations for harbour towage and escort operations.
“We are committed to expanding that fleet when the opportunity allows and when demand dictates,” he said. “We have always invested heavily in the ships, equipment and personnel, which we believe are needed to provide the level of service required by the industry, both now and in the future. Safety must at all times be our primary objective.”
“Safety must at all times be our primary objective”
Elsewhere in Europe, Boluda France is expanding its towage capabilities, specifically for container terminals, by ordering a series of multipurpose tug newbuildings from Piriou’s Vietnamese shipyard.
Up to eight tugs have been ordered for delivery during the next two years. The first two tugs are due to be brought into service in June this year. These azimuthing stern drive tugs are based on Piriou’s Omni Stern Tug 30 design with an overall length of just over 30 m.
Boluda France needed more powerful tugs to handle the larger container vessels and cruise ships calling at French ports, said general manager Denis Monserand. These newbuilds will have a top speed of 13 knots and combined propulsion power of 4,480 kW.
“This new series will be built with increased power compared to the previous generation, to reach 77 tonnes of bollard pull,” Mr Monserand said. “This will allow our crews to service vessels of ever-increasing size in the best conditions.” Each tug will have two main medium-speed, four-stroke diesel engines, rated at 2,240 kW driving two aft azimuthing propellers.
Svitzer tugs assist container ships into and out of terminals in Europe
Svitzer Europe invested in highly manoeuvrable tugs from Sanmar shipyard in Turkey for its UK operations that include supporting container terminals in the Thames. In November the latest in the Delicay series of tugs, Svitzer Meridian, entered service.
This is an azimuth tractor drive tug with 71.5 tonnes of bollard pull and combined engine power of 4,200 kW. “Svitzer Meridian is a versatile tug and will prove useful both at London Gateway and in the [river] Medway,” said Svitzer Europe managing director Kasper Friis Nilaus.
The first job for Svitzer Meridian was to assist container ship MSC Iris on its arrival in London in early November 2018. Svitzer Meridian is a sister vessel of Danish-flagged Svitzer Vale, which has worked in London and Bremerhaven, Germany over the last six months. Both tugs were built to an adapted Robert Allan TRAktor 2500-SX design and constructed to ABS class requirements.
In the US, tug owners also need to comply with Environmental Protection Agency (EPA)’s Tier 4 requirements for minimising particulate, NOx and SOx emissions, for newbuildings. Owners also need to upgrade capabilities for the ULCSs scheduled to berth at ports on both east and west coasts.
On the east coast, McAllister Towing expanded its fleet with powerful escort tractor tugs that comply with EPA Tier 4. The lead vessel of this Jensen Maritime Z-drive tug four-vessel series, Capt Brian McAllister, was built by Horizon Shipbuilding in 2017.
The second tug, Rosemary McAllister, was brought into service in Virginia in Q3 2018. Eastern Shipbuilding Group is building the last two of this series with Ava M. McAllister launched in December 2018 and Capt Jim McAllister due to be delivered by the end of this year.
These tugs have a pair of Caterpillar 3516E Tier 4 engines that each have a selective catalytic reduction after-treatment system for removing NOx. Combined, these engines generate 5,050 kW of power and drive two Schottel SRP 4000 fixed Rudderpropeller units for manoeuvrability.
McAllister vice president and general manager Elliott Westall said in Q3 2018 that Rosemary McAllister had made a huge difference to towage capabilities in the Hampton Roads area of Virginia. “We have seen a major increase in the arrival of ULCSs, and this tug, with its power, is able to expertly handle the largest vessels in the market today,” he said.
“We have seen a major increase in the arrival of ULCSs, and this tug is able to expertly handle the largest vessels in the market today”
It is not just its power that influences container ship handling though. “With its tethered escort abilities, Rosemary McAllister is a real game-changer,” said Capt Westall. “Bring on the 450-m container ships, McAllister and our team are ready!”
On the US west coast, Foss Maritime is also using Jensen Maritime designs for a series of up to 10 tugs for EPA Tier 4 requirements. Foss ordered four Valor tugboat design vessels from Nichols Brothers Boat Builders for delivery between Q4 2020 and Q4 2021. There are options to build six more for delivery from 2022 onwards.
They will have bollard pulls of up to 90 tonnes and equipment for towing, assisting and escorting ULCSs. Each will be powered by two MTU series 4000 main engines driving twin Rolls-Royce Z-drive propulsion units.
Nichols Brothers is also building a trend-setting escort tug of Jensen Maritime design for Baydelta Maritime’s US operations. It will have a Rolls-Royce hybrid propulsion system, including electric motors, shaft generators and a power management and control system, for tractor tugs.
This ABS-classed tug is scheduled to enter service at US west coast container terminals in March 2019 to assist ULCSs with reduced emissions and lower operating costs.
Salvage and emergency
Tugs are not just needed for manoeuvring vessels in terminals. Sometimes they are required to assist distressed container ships far from ports. In January, tugs were mobilised to assist Hapag-Lloyd’s damaged container ship Yantian Express, which was stranded in the Atlantic off North America.
Maersk Mobiliser sailed from the US east coast and Boskalis-owned Union Sovereign from Rotterdam to assist with the salvage. They were towing Yantian Express to a safe port, Freeport in the Bahamas, according to AIS data.
In October 2018, tugs were requested to assist container ship Iduna, which was stranded in the Baltic Sea while en route to Hamburg, Germany, due to machinery failure. Also in October, container ship Ying Hai started listing in the Taiwan Strait in rough seas. It lost containers, continued to list and then sank, south of Taiwan.
This demonstrated the risk of container ships sailing in adverse weather conditions. Another illustration of the effects of high waves on container ships occurred in January 2019 when MSC Zoe suffered from a parametric wave effect. This caused a damaging list on the laden ship and multiple containers toppled into the sea off the Dutch coast. There is an ongoing salvage of containers and other material on the Frisian islands and in the North Sea.
Bureau Veritas marine marketing and sales director Gijsbert de Jong said container ships should be navigated to avoid rogue waves. “The phenomena of parametric waves can be devastating,” he said. “We recommend that captains should avoid the risk from this and from storm weather.”
“The phenomena of parametric waves can be devastating”
Container ship masters can employ weather routeing programs to avoid storms and potential rogue waves. These programs can also predict tidal conditions close to ports to reduce the risk of container ship groundings blocking shipping channels and requiring tugs to refloat them.
There are several providers of weather information and e-navigation. ChartCo provides weather information as part of its OneOcean platform, launched in September 2018. ChartCo chief commercial officer Howard Stevens explained to CST that this platform delivers e-navigation, route and passage planning, environmental compliance and data management.
“With this information, masters can route ships around adverse weather, avoiding ice, swells and high winds,” said Mr Stevens, adding “All this information goes into a passage plan for optimising a route for time, total costs and fuel consumption.”
A voyage plan can be created by setting waypoints manually on electronic navigational charts or they can be imported from ECDIS. There is also a quick route process using OneOcean, said Mr Stevens.
Weather routeing services are based on MeteoGroup’s Ship Performance Optimisation System and enables seafarers and shipmanagers to execute container ship voyages for safety and reduced operating expenditure.