Bisso Towboat takes delivery of ASD tractor tug
SEPTEMBER 21, 2016 — Bisso Towboat Co., Inc. Luling, LA, has taken delivery of its newest ship-assist tug, the 4,480 hp ASD tractor tug Mr. Ruben. The Mr. Ruben is the first
SEPTEMBER 21, 2016 — Bisso Towboat Co., Inc. Luling, LA, has taken delivery of its newest ship-assist tug, the 4,480 hp ASD tractor tug Mr. Ruben. The Mr. Ruben is the first
JULY 31, 2016 – Horizon Shipbuilding, Inc., Bayou La Batre AL, recently delivered the M/V Marty Cullinan, a 120 ft towboat with a retractable pilot house, to its home port of New
Over the years, the use of azimuth thruster has changed the way operators do business. The increased maneuverability and efficiency gains allow tug operators to do more with the same installed power. Added maneuverability can also play a role in improving safety during certain operations. With more than 50 years of developing and manufacturing azimuth thrusters, Rolls-Royce has learned a lot about the specific propulsion requirements of different types of ships and floating structures. Working close with the customers has been a key element of the success.
Steerable azimuth thrusters have come a long way since the first one went into service in 1965. With just 80 hp of thrust it was installed on a mud hopper barge in Finland to make it self-propelled. The first azimuth units specifically designed for inland waterway applications were delivered in 1976. They powered a series of three-river push boats built in Holland and are still operating today.
With the aid of modern computer-based design tools and a detailed understanding of hydrodynamics, Rolls-Royce is continuously developing and improving its thruster product range. The current product portfolio covers a power range of 300 to 14,000 hp.
The benefits of Azimuth thrusters on a towboat
With an azimuth thruster the full thrust can be applied in any direction through the full 360 degrees and significantly improve the maneuverability and braking force of the vessel. In performance tests it has been shown that the braking forces produced are nearly 1.5 times those of the conventional towboat, over the whole speed range. This increase in braking force reduces both the distance and the time needed to stop a barge train.
For shallow draft operations, the normal requirement is to fit 2 azimuth units, and it is not unusual to have towboat designs with a triple azimuth thruster propulsion arrangement.
Azimuth thrusters also significantly increase flanking forces, which help operators safely navigate through the most difficult bends of the river. On a conventional towboat, flanking rudders and reverse thrust are normally used to produce the necessary flanking forces. By using azimuth thrusters the transverse force can be maximized and is approximately twice the maximum side force produced by a conventional towboat at all measured speeds, plus there is the benefit of greater braking forces. Maximum flanking forces produced can be up to 4 times that of the conventional towboat with equal braking force.
How Azimuth thruster help in Brazil
Brazil is a country traversed by many rivers, the main one being the Amazon. There are 11 main inland waterways with a total length of some 39,000 miles although only approximately 8,000 miles are regularly used. These waterways are used to transport agricultural commodities such as grain and fertilizer, as well as mineral goods to the coast.
Amaggi Navegação a subsidiary of Amaggi Exportação e Importação Ltda. is one of the operators working in the region who has moved to azimuth thrusters to propel their vessels. They have been operating on these waterways for over 20 years and now have over 30 tugs equipped with azimuth thruster propulsion. Units in their fleet include a range of Rolls-Royce thrusters from our smaller US 105 model to our larger US 255’s.
Amaggi Navegacao operate on the Madeira and Amazones rivers where they are involved in the transportation of grain and soya to and from local processing plants. The move away from conventional towboat design has enabled them to increase the size of barge trains, which is due to increased turning and stopping capacity at full load.
Open prope
llers are used for the majority of these thruster applications due to the amount of debris in the rivers. The trend outside the Amazon is to fit azimuth thrusters with nozzles and thereby maximize thrust.
The future of Azimuth thrusters
Thruster technology continues to develop. The latest is the introduction of gearless electric drive through the application of permanent magnet (PM) rim drive technology, where the motor surrounds the propeller as a slim ring. The rotor is integral with the propeller and carries a series of permanent magnets. As the magnetic fields interact, the propeller turns. Tunnel thrusters and azimuth thrusters utilizing this technology are now available from Rolls-Royce. The compact and efficient tunnel thruster unit is easy to install and power output is increased by around 25% for the same propeller size. It is a good example of the possibilities that lie ahead.
This technology has now been applied to the azimuth thruster by Rolls-Royce, and the first PM development thrusters rated at 670 hp were installed on the research vessel R/V Gunnerus in March 2015. Nozzle shape can be selected to suit individual applications, but since Gunnerus requires pull for towing trawl and other gear, the nozzle is optimized for bollard pull and speed to match the vessel’s requirements. The installation is compact with only the slip ring unit and the variable frequency steering motors inside the hull.
Before the installation, the vessel had a conventional diesel electric propulsion system consisting of frequency converters, induction motors, gears and shaft with nozzle propeller. Testing to date has demonstrated an improvement in propulsive efficiency and bollard pull with a reduction of air and structure borne noise and vibration.
MAY 6, 2016 — Eastern Shipbuilding Group, Inc.’s Allanton. FL, shipyard has delivered the 90 ft inland towboat M/V Lawrence Campbell to Florida Marine Transporters, LLC, Mandeville, LA. Built to a design
APRIL 5, 2016 — Ingram Barge Company has chosen GE Transportation 8-cylinder, 250 mm bore inline medium speed (1,000 rpm) Tier 4 compliant marine diesels, supplied through and distributor National Maintenance &
MARCH 9, 2016 — Kirby Corporation (NYSE: KEX) reports that it has agreed purchase the Seacor Holdings Inc. inland tank barge fleet for approximately $88 million in cash. The asset purchase will
MARCH 1, 2016—Gulf Island Shipyards, LLC, a subsidiary of Gulf Island Fabrication, Inc., recently delivered the Loree Eckstein, the second of three 10,000 hp towboats, to Marquette Transportation Co., Paducah, KY, at
JANUARY 14, 2016 — The American Waterways Operators, the national trade association for the tugboat, towboat and barge industry, has promoted Jennifer Carpenter, its Executive Vice President, to the position of Chief
DECEMBER 28, 2015 — Eastern Shipbuilding Group, Inc., Panama City, FL, reports that its Allanton shipyard recently delivered M/V Harvey Sbisa (Hull 192). The 90 ft inland towboat is the sixty second
The vessel, built by Vigor Industrial’s Portland, OR, shipyard, follows towboat Crown Point, which began operations along the Columbia Snake River in May 2015.
Like the Crown Point, the Granite Point is a custom-built, environmentally-friendly towboat that was specifically designed by naval architects and marine engineers CT Marine, Edgecomb, ME, to serve Tidewater’s customers.
“Granite Point performed exactly as we wanted it to during its river trials earlier this month,” says Marc Schwartz, Maintenance & Engineering Manager at Tidewater. “We are ready for the Granite Point to team up with Tidewater’s current fleet of 16 towboats to provide our customers with the highest quality river transportation.”
Named for the granite cliff in Washington, about 20 miles southwest of Pullman along the Snake River, the towboat was built to the same specifications as the Crown Point and forthcoming sister vessel, the Ryan Point.
Measuring 102 ft by 38 ft, with a depth at full load of 11 ft, the Granite Point has a hexagonal wheelhouse with floor-to-ceiling windows on all six sides. The hexagonal design continues to the main deck, which features a galley, a media room, and a health and fitness facility.
“Tidewater understands that the ability of our crew members to cope with operational risk factors, like frequent sleep disruptions and heavy workloads, depends on their level of endurance,” says Bruce Reed, Chief Operations Officer and Vice President of Tidewater. “The responsibility for maintaining a high level of crew endurance rests with us. Therefore, all three towboats incorporate a comprehensive sound and vibration control package designed by Noise Control Engineers of Billerica, Massachusetts. The noise levels register at less than 60 decibels in the quarters during vessel operation, which is equivalent to the sound of an air conditioner.”
“When you are in the wheelhouse, which is three decks above the engines, you would really need to concentrate to hear the engines at all,” says Brian Fletcher, Tidewater Port Captain who piloted the Granite Point through river trials.
“You couldn’t ask for a quieter tug, nor a better tug in tight situations. It turns on a dime.”To meet the challenges of maneuvering barges through swift-moving currents, high winds, and eight navigation locks along the CSR System, CT Marine designed an enhanced steering system utilizing four main steering and four flanking rudders. Coupling the steering system with two Caterpillar 3516C Tier 3 engines, the design team was able to increase the margins of safety and efficiency.
“The Granite Point can ‘get up and go’,” says Josh Nichols, Assistant Port Captain, “but there is an ease and steadiness to it.”
“The up-front work paid off,” says Bob Curcio, Tidewater CEO. “The vessels are fuel-efficient, ecologically-responsible, and are giving our Captains and crews exactly what they’d asked for.”
“We are proud to have worked with Tidewater on Granite Point. Like its sister ship Crown Point, this vessel sets new standards for future towboat design. It will serve our community well for decades to come,” says Corey Yraguen, Vigor Executive VP of Fabrication.
TECHNICAL PARTICULARS
The Granite Point is powered by two Caterpillar 3516C EPA Tier 3 certified diesel engines each producing 2,240 BHP at 1,600 RPM. The engines drive two 92″ x 100″ fixed pitch, stainless steel propellers through CT28 Kort Nozzles. The vessel is capable of a service speed of 8 knots.
Electrical power is provided by two C7.1, Tier 3 generators, rated at 480 V, 200 kW at 1,800 RPM. The generators are controlled through an automatic transfer system that ensures the vessel will recover from a generator power loss in less than 30 seconds.
Deck machinery includes seven Patterson WWP 65E-7.5, 65 ton electric deck winches, with pilot house remote operation and local push button control stations on the main deck. Each winch has Samson 1 3/8″ Turbo 75 Synthetic Line.
To minimize power usage, variable frequency drives were used in all major rotating machinery applications and LED lighting was employed in both interior and exterior lighting applications.
The vessel is fitted with a Kidde NOVEC 1230 fire suppression system. Centralized fire detection and alarms cover both the machinery spaces and accommodations.