Pacific Maritime Magazine - Marine Business for the Operations Sector

Earl W Redd: Harley Marine's New Tier 4 Tug


The Earl W Redd has attracted national attention as the first vessel in the world to be powered by Caterpillar's Tier 4 version of the 3516E engines. Photo by Kurt Redd, courtesy of Diversified Maine.

Portland, Oregon-based Diversified Marine has delivered the new 120-foot tractor tug Earl W Redd to Seattle-based Harley Marine, for use within its Olympic Tug & Barge division. The Earl W Redd has attracted national attention as the first vessel in the world to be powered by Caterpillar's Tier 4 version of the 3516E engines.

Harley V. Franco started Harley Marine Services in 1987 with a single tug, and in 30 years has succeeded in growing the company into a national player with more than 100 vessels operating around the entire US coastline. From its headquarters in Seattle, Washington, the company has built a reputation for innovation, including its goal of operating the cleanest and most environmentally-friendly vessels using the best-available technology. This includes its ISO certifications that require an annual audit by the American Bureau of Shipping's Quality Evaluations team.

In the last five years, Harley has commissioned five ship-handling tugs from Diversified Marine of Portland, Oregon – all powered by Caterpillar 3500-series engines meeting EPA Tier 3 standards. The Earl W Redd, the sixth in the line from the Portland yard, keeps the company at the forefront of low-emission diesel technology by meeting the strict Tier 4 standard a year in advance of the legal requirement.

Caterpillar's Tier 4 E-Series

The E signifies that these engines, supplied by Peterson Power Systems, have been re-engineered to run with a completely new form of emission control: a selective catalytic reduction (SCR) after-treatment system that injects a urea-based diesel exhaust fluid (DEF) into the exhaust stream to convert the oxides of nitrogen (NOx) contained in diesel exhaust to nitrogen and water vapor. Notably, Caterpillar Marine claims a 10 percent horsepower increase over the Tier 3 version, giving the E-series ratings of 2,501-3,386 bhp (1865-2525 bkW). The engines specified for the Earl W Reddeach provide a continuous 2,682 HP at 1,600 rpm. The power provided by these clean new engines is a welcome addition to the Harley fleet, as the new boat is intended for long-haul coastal towing year round on the Pacific Coast.

Much of the improvement comes from a re-engineering of the emission-control technologies. In the most recent, Tier 3 technology, exhaust gas recycling took place inside the cylinder head. This function has now been moved off the engine and into a separate modular SCR chest, improving the efficiency of the combustion cycle. "These engines are able to deliver an increased level of performance with higher power rating," says Ryan Darnell of Caterpillar's Large Power Systems division. "That's a direct result of our SCR technology that allows us to reduce NOx downstream of the engine combustion process."

Flexible SCR Placement

The position of the SCR chamber depends on the size and layout of the engine room. On this tug, the exhaust is directed up from the engine room in the normal way, then takes a right-angled turn past the urea injection port and into the SCR chamber located forward of the stacks in the fidley on the main deck. It measures 6.5-feet long, 5.25-feet high and 3.3-feet deep, plus the insulation blanket, and is equipped with sensors to measure the percentage of the exhaust gases before and after treatment. The urea is stored in a pair of 4,100 gallon tanks under the aft deck that are sufficient to treat the maximum fuel load/capacity of 127,000 gallons at the standard 5 percent rate.

The urea is held in a four-gallon day tank on the engine room bulkhead with an integrated pump and computer that controls the air/urea mix and dosing pressure. There are no other additional components required when using SCR, Caterpillar states, calling the system durable, reliable and technically robust. "Harley Marine should save more than $1 million across a 15-year lifecycle on total fluid consumption (diesel plus DEF) costs for this new build compared to an equivalent Tier 2 powered vessel," Darnell explained. The vessel is propelled by a pair of Rolls-Royce RR 255/3800 FP azimuthing drives with stainless steel propellers.

The engine room has been carefully specified for reliability and includes carbon fiber shafts from Vulkan, Cooper shaft bearings and Rubber Design mounts. The keel coolers are by Duramax, and a Kidde FM 200 fire-fighting system keeps the machinery spaces safe. A pair of Tier 3,150-kW John Deere 606 8AFM85 gensets supply electrical power to the winches, hydraulics, Alfa Laval fuel separator, Quincy air compressors and US watermaker. The ship's service switchboards and consoles are all supplied by Techsol of Quebec City, Canada and tested on board by company technicians.

The Earl W Redd, with a beam of 35 feet and draft of 19 feet, is the twelfth Titan to launch in the Pacific Northwest. This versatile design has proved itself over 20 years hauling heavy barges to Alaska and across the Pacific. Harley's first Titan was given an ice-strengthened bow for ship handling in Cook Inlet, Alaska. The Earl W Redd has a bollard pull of approximately 80 tons ahead and 70 tons astern, while the fendering is a combination of Shibata cylindrical and Schuyler laminated rubber on the bow and stern, with aircraft-grade tires amidships.

Markey Winches Fore and Aft

Markey supplied both the head winch and the towing winch. On the foredeck is a Markey Model DEPC-48-50HP Electric Hawser Winch weighing approximately 18,700 lbs. It has a drum capacity for up to 500 feet of 9-inch soft-line, and includes the Markey Render/Recover and NexGen controls. The winch is powered by a standard AC-variable frequency winch drive with dynamic braking resistor bank.

The towing winch is a Markey Model TESD-34-100HP Electric Single-Drum Towing Winch with an estimated weight of 62,000 lbs, driven by a 100HP 460/3/60 AC-Variable Frequency Drive. The starboard drum is sized for up to 2,500 feet of 2-1/4-inch wire rope, port drum sized for up to 1,500 feet of 2-1/4-inch wire rope. The brakes are manual/air-controlled drum with drum disconnect clutches. There is a standard chain-and-diamond-screw level-wind (on the starboard drum only), and an 18-inch diameter warping head, with rope-guide. An optional load-shedding system and a come-home drive are provided. A new feature is Markey's touch screen display, allowing operators more control over wire scope and line tension. The tow pins were supplied by Smith/Berger.

The Earl W Redd has accommodations for 6-8 crew in three spacious double cabins with independent Daikin climate control units, heads and showers, and separate staterooms for the captain and chief engineer. The galley is equipped with commercial-grade appliances including an Avant Edge freezer and refrigerator, and an Imperial range. In keeping with Harley's environmental policy, the vessel it fitted with MarineFAST LX-Series Certified Type II Marine Sanitation Devices (MSD) with biological (aerobic digestion) system to treat all blackwater and graywater generated on board.

Climate Controlled Pilothouse

The Earl W Redd is equipped with Furuno navigation electronics and a Simrad autopilot, while heating, cooling and ventilation is provided by a Daikin system utilizing heat pumps. Photo by Kurt Redd, courtesy of Diversified Maine.

The pilothouse is equipped with Furuno navigation electronics and a Simrad autopilot. All lighting is LED, supplied by the Carlisle & Finch Co. The custom-built closed-circuit video system was selected and engineered by Pinnacle Digital Surveillance in Vancouver, Washington. The helm chair was supplied by LeBroc. With all the glass in modern pilothouses, heating and cooling are equally important and one of Harley's innovations is to fit Daikin heat pumps on their recent tugs for heating, cooling, ventilation.

The Earl W Redd is equipped with the latest Daikin VRV IV 6-ton model with Variable Refrigerant Temperature control cycle for improved efficiency, mounted beside the pilothouse ladder. These Daikin units use a variable speed compressor that puts a lower load on the generators. The Harley machine shop modifies these appliances to withstand salt-water exposure, and adds vibration isolators and a steel-grid enclosure.

The Earl W Redd is named after the father of Kurt Redd, owner and manager of Diversified Marine.


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