JonRie is installing its first hydraulic Tri-Winch on tugs and Rolls-Royce has unveiled a lightweight winch with a permanent magnet electrical motor
JonRie InterTech’s new Tri-Winch was first installed on tugs in 2017 for escort operations over the bow or from the stern. These new units were installed on three Rotortug vessels Trident, Triton and Trinity for Seabulk Towing.
These 33-m tugs were built by Master Boat Builders of Bayou La Batre, Alabama, to a Robert Allan ART 80-98US-design. They have a bollard pull of 78 tonnes provided by a set of Caterpillar 3512C diesel engines, JonRie’s winches and serve Port Everglades, Florida
Tri-Winch was designed for escort operations fore and aft, and long-line towing over the stern, said JonRie InterTech president Brandon Durar. He pointed out that new features include honeycombed drums and dual-power units allowing the winches to be operated independently from vessel power.
Other features include its dual-foot control “to allow for hands-free operation of each winch, press-down to payout and heal-back to haul-in” said Mr Durar.
Unique to Tri-Winch are its three winches and its drives, “which are all independent and direct for each drum from the gypsy to the level wind,” he explained.
All operations can be conducted from the wheelhouse and “are safe operations as no one is needed on deck for each operation once the lines are hooked up.” These winches also have JonRie’s own tension display for each drum, which has sidelights and dimming for night use.
Tri-Winch hawser winch drums have the capacity to spool 165 m of 20.3 cm hawser, a line speed of 35 m/min and a brake capacity of 300 tonnes. Its “direct drive design allows for a quick response to fast loading inertia that an escort winch must endure,” said Mr Durar.
Its towing drum has the capacity to spool 700 m of 58 mm line. The dual hydraulic power units can be cross-connected to run one winch at a faster line speed and for independent operation of both bow and stern drums.
Mr Durar said these winches were suited for Seabulk’s Rotortug fleet because they could be controlled hands-free from the pilothouse by a master with a clear line of sight across the deck.
He is a proponent of hydraulics for driving winches, as he thinks they are “suited for today's tugs with respect to reliability”. He also said that tugs are designed with solutions to ensure hydraulic fluids are unable to enter the environment.
All JonRie designs use a direct-drive Hagglunds hydraulic motor “which has a very low moment of inertia” said Mr Durar “so when the motor is being overhauled it can take the extreme forces of the tug.” This makes these drives “very well suited for render and recover features, controlled freewheel modes and paying out line under load.”
JonRie is currently working on a design with a direct-drive level wind using the same technology.
Rolls-Royce PM technology
Rolls-Royce Marine has introduced a new lightweight winch driven by a permanent magnet (PM) electrical motor for tug towage. This XT70 PM escort, render and recovery towing winch provides enough pull for most oceangoing and harbour duties without the risk of oil leaks from a hydraulic drive.
XT70 PM was added to the portfolio of towing and escort winches developed specifically for tug operations this year. It can deliver up to 75-tonnes pull on the first layer at 36 m/min, said Rolls-Royce Marine vice president of sales for deck machinery Kjetil Nilsen.
Its motor has a nominal speed of 65 rpm and a nominal torque of 70 kNm. But it can operate with a nominal speed of 100 rpm with a 690 V alternating current power supply. If a tug operator needs higher motor speeds, XT70 PM can operate an overspeed of 170 rpm, close to three times its nominal rating with a third of the torque, Mr Nilsen explained to Tug Technology & Business.
It has a low gear ratio, which provides less gear losses and better dynamic performance of the winch. The PM motor can also provide regenerative power back to the ship’s switchboard, if the vessel is so equipped. Mr Nilsen said this feature makes it suited for a tug with a hybrid power system.
He thinks this equipment, as well as other hydraulic- and electric-driven winches in the Rolls-Royce portfolio, would be suitable for icebreakers operating in arctic conditions. XT70 PM is also suitable for emergency towing operation, coastal towage or to be installed on multipurpose vessels. It was developed in 2016 when Rolls-Royce secured a contract with US tug owner Edison Chouest to supply towing winches plus auxiliary winches, all based on low-pressure hydraulics.
Mr Nilsen said this contract made the deck machinery team at Rolls-Royce consider “how winch systems for the tug market could benefit from using low-pressure hydraulics, but also if an electro engine would benefit tug operators and their crews”. PM driven electric motors compare well with hydraulic systems and offer high torque and dynamic performance and environmental benefits, he said.
Rolls-Royce had already developed PM technology for propulsion systems, mainly tunnel and azimuthing thrusters and used this experience to develop a PM motor for winches to mirror the performance of low-pressure hydraulic motors.
In 2016, Rolls-Royce introduced the XT140 PM winch for fishing vessels and this experience was also used to develop the XT70 PM winch. As of July this year, 10 XT140 PM winches are installed on fishing vessels and 15 more trawl winches of this type are on order.
“A highly efficient electro motor reduces the risk of pollution from an oil spill,” said Mr Nilsen. Its improved efficiency “reduces the overall fuel consumption of the vessel, and the winch is designed to reduce installation and maintenance costs.”
Edison Chouest tug newbuilding order
Edison Chouest ordered 13 oceangoing heavy-duty mooring assistance and escort tugs from Damen Shipyards in October 2016.
Nine of these are azimuth stern drive (ASD) tugs built to operate in Alaska where Edison Chouest started providing ship escort and response duties out of Valdez and Prince William Sound in July 2018. Four other ASD tugs will support LNG carriers at a Corpus Christi-based LNG export terminal in Texas.
Rolls-Royce equipped the five largest ASD 4517 escort tugs, which have bollard pulls up to 150 tonnes for operations in Alaska, with winches capable of dynamic towing in the full bollard pull range. This was instead of towing on static brake, which is more common for these type of vessels. This dynamic towing capability of the low-pressure hydraulic winches reduces wear and tear on the tow gear.