Legacy: Crowley’s new ATB demonstrates what the biggest of them all can doJun 19, 2012 11:45 AM
Legacy’s 330,000-barrel tank barge takes on a cargo of gasoline at the Marathon Oil terminal on the Mississippi River in Garyville, La.
At 1624 on a breezy day in early March, the recently delivered seagoing tug Legacy, coupled to the tank barge 750-1, cleared the jetties at the mouth of the Mississippi River, made the Southwest Pass Sea Buoy and entered the Gulf of Mexico, bound for Tampa, Fla.
The voyage had begun the previous day from the Marathon Petroleum dock at Garyville, La., mile 140 above New Orleans. At 0924, Capt. Rodney Hight of the Associated Federal Pilots & Docking Masters of Louisiana boarded and joined Capt. Calvin Patterson, Legacy’s master, on the bridge. With the assistance of E.N. Bisso’s tug Jackie B and Crescent Towing’s tug Providence, the 674-foot articulated tug-barge (ATB) was turned and headed downriver towards New Orleans.
A 2,000-pound Danforth anchor hangs from the stern as the tug crosses the Gulf.
Crowley Maritime Corp. owns, operates, manages and crews Legacy and 750-1, on charter to Marathon Petroleum. The 148-foot, 16,092-hp Legacy was built at Dakota Creek Industries in Anacortes, Wash., and the 330,000-barrel 750-1 was built at VT Halter Marine in Pascagoula, Miss. The pair were joined last fall in Pascagoula, christened last November in New Orleans and put into service in January 2012. Two more in the series, Legend and Liberty, will depart Dakota Creek to join barges 750-2 and 750-3, respectively, this spring and summer in Pascagoula.
Fog had plagued traffic on the river for several weeks, so soon after passing New Orleans and rounding Algiers Point, Hight checked on the weather farther south. Sure enough, fog was expected to move into Southwest Pass at the mouth of the river later in the afternoon. With 100 miles of river to run and a diminishing number of anchorages to choose from, Hight and Patterson decided to anchor at Belle Chasse. At 1420, Bisso Towboat’s Michael S and E.N. Bisso’s Peggy H turned the ATB and eased it over, close to the west bank of the river, where the port and starboard bow anchors were dropped.
At 1530, a Stone Fuel bunker barge came alongside, and Legacy took on heavy fuel oil (HFO) to feed the two Wärtsilä W12V32 diesel mains housed in completely separate machinery pods, port and starboard. Enclosed in each of the pods is a main engine with a Wärtsilä 4.480:1 reduction gear and a main shaft culminating at a Wärtsilä controllable-pitch propeller. A second shaft turned by a PTO, off the main engine and gear, drives a Marelli Motori 684-kW shaft generator.
Second Mate Rob Cope plots a course change.
Crowley has been working up to ship-sized ATBs with cargo capacities competitive with coastal tankers. In 2002, the company took delivery of the 9,280-hp tug Sea Reliance and the 155,000-barrel barge 550-1. The 650 series followed with the first of ten ATBs, the 10,500-hp tug Pacific Reliance and the 178,000-barrel barge 650-1 delivered in 2006.
Crowley reports that the 750 series ATBs are the largest, fastest and safest ATBs yet built. They are also the first tugs to utilize the concept of isolated engine room pods.
Next morning at 0930, with a light fog lifting, Capt. Jaime Colon of the Associated Federal Pilots & Docking Masters of Louisiana came aboard. Colon consulted with Patterson on the fog, traffic and the handling characteristics of the 750 class of ATB, still unfamiliar to the pilots. The tugs Peggy H from E.N. Bisso and Allison S from Bisso Towboat took the bow, and after the ATB weighed anchor, the tugs guided the ATB into the current, directing it downriver.
There are four sets of pilots on the Lower Mississippi River. The Associated Federal Pilots & Docking Masters of Louisiana are licensed to guide all U.S. flagged, coastwise ships on the Lower Mississippi from the sea buoy outside of Southwest Pass in the Gulf to Baton Rouge. The three other pilot associations are licensed to guide foreign-flagged and U.S. ships from the sea buoy to Baton Rouge in the following order: the Associated Branch Pilots from the Southwest Pass sea buoy to Pilottown, the Crescent River Port Pilots from Pilottown to New Orleans, and the New Orleans-Baton Rouge Steamship Pilots from New Orleans to Baton Rouge.
From the Belle Chasse anchorage, most of the serpentine course of the river was behind us, but still there was no lack of ships, barges, fleeting and lightering operations, commercial fishing boats, dredges and a couple of ferries — plenty of traffic to keep a pilot and captain alert.
Dave Cunningham on the bridge. He will serve as second mate aboard a sister vessel.
Patterson is a hawsepiper who holds an unlimited master’s license. After eight years in the Navy, he hired on with Crowley as an AB 15 years ago, eight of them on the steamships Blue Ridge and Coast Range, both recently scrapped and replaced by the 750 series ATBs. He is impressed that Crowley transferred many of the crewmembers from the steamships over to the 750s, especially given the differences between the machinery and the manning of a steam-powered ship and an HFO- and diesel-powered tug.
“Crowley is also keeping extra crew on here as trainees to go on the next two boats (Legend and Liberty),” said Patterson. “I appreciate that too. They could have sent them home and said, ‘Come back when the boats are ready.’ So it is good of Crowley to keep them working, making a wage and feeding their families. And when the boats are ready, we have trained people to work on them.”
At Head of Passes Legacy reached the confluence of Southwest Pass, South Pass and Pass-a-Loutre, three prongs of water that finger their way toward the Gulf of Mexico. In this area, the little land that remains is fast giving way to water. In Southwest Pass the banks finally gave way to the jetty and then the Gulf. At the sea buoy, Colon boarded the pilot boat, bound for an incoming ship.
Patterson struck a course for Tampa and turned the bridge over to the second mate, Dave Cunningham, a graduate of Massachusetts Maritime Academy who formerly served on Blue Ridge. He was on board Legacy for training as a second mate on Legend, due out of Dakota Creek at the end of March. AB Tom Tramutola was at the helm.
The watch had no sooner settled into the routine of a Gulf crossing when Patterson came on the bridge and announced a change of orders. Instead of Tampa, Legacy was to sail to Port Everglades, Fla., and discharge the premium fuel in two of the barge’s 14 cargo tanks. Then it would sail back around the tip of Florida to Tampa, discharge the remaining tanks of regular-grade gasoline, and then return to Garyville.
Capt. Calvin Patterson engages the Intercon coupler pins that lock the tug in the notch.
The change brought Rob Cope, the official second mate on Legacy, onto the bridge to set up the new voyage routes. As on a ship, the second mate on an ATB is the navigation officer. As well as standing a watch, he is on call at all times for navigation issues and for all maneuvers. Cope attended Texas A&M University and has an unlimited second mate’s license. Crowley requires that all the officers on board hold an unlimited license at whatever level they are employed.
“It’s my duty to set up our routes, set the voyage route on the GPS, set up the charts in order for the voyage, and set the communications references from Voyage Plans which lay out a voyage from point A to point B,” said Cope. “I also change the nav lights and update the charts, the publications and the notice to mariners that are specific to our inventory of charts and publications.”
Over the course of the night, the wind picked up to 30 knots and seas, at 8 to 10 feet, set up a rocking-horse motion in the tug as it rotated on the Intercon coupler in the notch of the barge. It was an unusual sensation, the tug rocking while the barge remained on an even keel, but it soon began to feel normal. At the sea’s peak, the coupler, rated for 25° of articulation, was swinging the tug through 12°.
The Intercon coupler on Legacy is gigantic, specially built for the 750 series by Intercontinental Engineering-Manufacturing Corp. of Kansas City, Mo. The ram diameter is 64 inches compared to the 50-inch diameter ram on the 550s and 650s. The rams, located at the bow of the tug, port and starboard, have teeth that, when extended, engage with a continuous tooth-patterned ladder receptacle built into each side of the notch in the stern of the barge.
When the rams are set, or “pinned,” they are locked and the unit is ready for travel. When in port, after mooring, the rams are retracted and turned so that the teeth face up and down. They are then extended back into the ladders, engaging in an unlocked mode that allows the barge free vertical movement as it takes on or discharges product, resulting in changes in the barge’s draft.
The Intercon coupler room. The rams in the coupler system are 64 inches in diameter.
Out on the barge during the day while the ATB is underway, the off-watch mates and AB/tankermen work under the chief mate, Andrew Stewart, a graduate of Cal. Maritime. Coming down the river, the barge crew had been busy setting the mooring lines up for a starboard mooring in Tampa. They also readied the barge for discharging product: testing the power to the cargo pumps and the emergency shutdown systems, plugging and dogging the scuppers in the containment barrier and so on. Port Everglades dictated a port mooring, requiring the crew to walk the lines back across the barge to the port side.
The tasks required of the deck crew on 750-1 are fundamentally the same as on a tanker. Where the two differ is in crewing. For example, the 600-foot, 331,000-barrel State class product carriers that Crowley Maritime manages and crews for American Petroleum Tankers have a crew of 21. The 750 class ATB has a capacity of 330,000 barrels and a crew of 14. Reduced crewing regulation is at the heart of an ATB’s attractiveness.
“We don’t have a bosun, and the ABs are expected to do a lot more on the barge than they would on a ship because of the limited manpower,” said Stewart.
The mates are responsible for machinery and engine maintenance, some of which, on a ship, would be conducted in the engine room by the engineers, although the engineers on Legacy do repairs and train the mates on maintenance. However, the 750 series barges have a number of automated systems that eliminate some of the labor. For example, all the valves on the barge are remotely operated from the cargo control room and the tanks are radar monitored and have a fixed-tank washing system.
“One of the things I really like about this barge is the tank stripping system,” said Stewart. “Each tank has a suction on the sump as well as on the top line, and so the vacuum tank strips out every last bit of fuel. You don’t have to wash the tanks in between stripping them and then purging them. It’s one of my favorite things about the barge because of the savings in time and manpower. We are on short runs, so we don’t have much time between ports to get ready.”
Another innovation is the separate vapor recovery and inert gas (IG) system. “We can line up the diesel tanks to the IG system to vent to atmosphere” in the tanks, said Stewart.
“The vapor recovery system sends the vapors ashore while loading. On the discharge, I simply open two crossover valves between the systems, and they are now common, ready for discharge.”
The tug and its barge heading southeast across the Gulf of Mexico on a route around the southern tip of Florida. With a design speed of 15 knots, the ATB was able to make 16.5 knots when going with the Gulf Stream.
The system replaces the vapor atmosphere in the tanks with inert gas while discharging product, rendering the tank noncombustible. “We’ve been pumping 30,000 barrels an hour and the system has no problem keeping up with it.”
750-1 is one of the first barges with an ODME (oily discharge monitoring equipment) that automatically shuts off water being discharged over the side if the oil content in the water exceeds allowable limits. Most of the water pumped over the side is from tank washing and well within regulatory limits, and the tank stripping system on the 750s almost eliminates the need for tank washing anyway.
At midnight Legacy rounded the Dry Tortugas, entered the Straight of Florida and by 0800 was in the Gulf Stream, 20 miles to the east of Key West. Traveling with the northbound current, Legacy was making 16.5 knots, about 2 knots more than in the Gulf of Mexico.
Cook William Sanchez sautés onions in the galley. Legacy would normally carry a crew of 14, but on this trip it had some others aboard who were preparing for the day they would operate Legend, the second ATB in this class.
In the engine room, a good deal of time is spent writing the book on procedures and creating an inventory of parts. “This is the first boat out, so we’re still entering items into the manual,” said the chief engineer, Tim LeClair. “We’re also writing up procedures like the sequence for main engine startup and the procedures for loss of power and loss of steering and so on.”
Legacy’s engine room is a watch standing one, and on a short run, such as to Tampa and/or Port Everglades from Louisiana, there is not much time between maneuvers and watch keeping to spread the workload around.
“On this run you’ve got a lot to do, and all the engineers are trained to handle all of the engine room duties,” said LeClair. “And we spend a lot of time on the barge, training the mates on maintenance.”
That evening and all of the next day, Legacy was in a controlled drift off Port Everglades, waiting for a berth. At midnight Capt. Preston Shelton, of the Port Everglades Pilots, came aboard, and with the assistance of the Seabulk Towing tugs St. Johns and Fort Lauderdale, Legacy made the short transit through the entrance channel, was turned bow for stern in the turning basin and backed into its berth. All fast was declared at 0130. Discharging the cargo of premium gasoline was expected to take about 16 hours.
One of two Wärtsilä 12V32 engines, which generate a total of 16,092 hp. Each engine occupies its own machinery space in pods that form the lowest parts of the hull.
“When I’m going into any port I’m thinking about outbound traffic that might affect my transit into port,” said Patterson. “I’m also thinking about weather conditions. A strong storm cell in the vicinity might cause me to consider not going in just then. You want to make sure all the aids to navigation are working. Port Everglades is not a difficult port from a navigation point of view, but there are so many small pleasure craft going in and out of here. For the most part, the large rudders on these vessels make it easy to turn and stop.”
At 1755, with a stiff 30-knot wind blowing directly onto the bow of 750-1 from the east, Capt. Sam Stephenson of the Port Everglades Pilots came on board. The Seabulk tug Broward took a position amidships on the starboard side of the barge and Legacy moved slowly along the pier, across the turning basin and into the channel leading to the Atlantic Ocean. Once through the short channel and past the sea buoy, Legacy turned south toward the U-turn at the Dry Tortugas. From there the next morning, the largest ATB yet built struck a course due north for the Tampa Safety Fairway.