Western Moves Ahead with High Tech Power

On June 15, Western launched its largest piece of high-performance machinery to date: the 120-ft. (36.6 m) Gulf Titan which is 12 ft. longer than Western's two previous builds, the Western Titan and Pacific Titan. As with those two vessels, Western built the new Gulf Titan with design assistance from Jensen Maritime, Seattle. The added length will improve sea-keeping characteristics and increase fuel capacity by 40,000 gallons, says Bob Shrewsbury, Jr., president of Western Towboat Co., Inc. And a new five-blade propeller design with added pitch is expected to coax an extra 2,000 lbs. of bollard pull from the twin Z-drive propulsion system with high-performance nozzles.

The Gulf Titan entered service in late July, towing a 14,000 long ton displacement combination railcar/container barge between Seattle and Whittier, Alaska. Propulsion power comes from two Cat 3516B High Displacement marine diesel engines supplied by N C Power Systems, Seattle. Each electronically controlled Cat engine is rated 2,260 bhp at 1,600 rpm, and drives an Ulstein Z-drive with Nautican propeller and nozzle. The Gulf Titan is equipped with a Norwegian Rapp-Hydema tow winch holding 2,600 ft. of 2.25 in. wire. Two 1,800 rpm Cat 3306B engines provide auxiliary power: one turns a refurbished Cat 135 kW generator, and the other powers a 120 kW Newage generator and a front-engine PTO-mounted hydraulic drive for the tow winch.

Cat 3516B High Displacement engines provide propulsion power for all three Titan vessels. These engines feature a longer stroke compared to standard 3516B electronic engines, providing more power and torque without significantly increasing engine package size. With a longer stroke, these engines can take in a larger air charge and attain more complete combustion of the fuel and air mixture. This helps reduce emissions as well as improve power. Compared to an equivalent 1,600 rpm rating for standard Cat 3516B engines, each high displacement engine adds 260 bhp.

"For our new line-haul boats, we need continuous 2,000 horsepower from the engines," says Bob Shrewsbury, Jr., president of Western Towboat Co., Inc., "With standard Cat 3516Bs we would need to run the engines pretty hard, but we get full power from the high displacement engines at 1,450 rpm. That gives us plenty of reserve power, and we expect to see benefits in life expectancy over the long term." Shrewsbury points out that spec-sheet performance-fuel rates, lube oil consumption levels, and vessel bollard pull-plays an important role in performance.

Intimate knowledge of major machinery, diligent maintenance and expert service keep breakdowns at bay. But the effort to reduce maintenance costs extends beyond major machinery, seemingly to every square inch of ship surface.

Clear deck areas with boxed-in bulwarks and judicious use of stainless steel for railings and enclosed areas all make maintenance chores easier. Western was an early proponent of shaft seals in place of stuffing boxes, reducing shaft wear and bilge pumping requirements.

More recent maintenance reduction efforts involve use of Centa carbon fiber shafts and couplings, and a new Airsep crankcase fumes disposal system. The first set of carbon fiber shafts was installed on the Pacific Titan, which entered service in May 2000. The new shafts reduce sound levels as well as maintenance needs, and similar shafts are installed on the Gulf Titan. Western is testing a new crankcase fumes disposal system for Cat 3500 engines on several of their vessels. According to Ed McEvoy, Western's port engineer, intake combustion air is much cleaner with the new system, extending air filter life.

With the addition of the Gulf Titan, Western's fleet now totals 17 vessels. Of these, eight are powered by mechanically actuated Cat 3500 engines, two are equipped with electronically controlled standard 3516Bs, and the three Titans crank out the highest power levels with 3516B High Displacement engines.

Western has been operating two Cat 3516B High Displacement test engines since February 1998. Cat 3516B High Displacement engines are contributing to Western's overall effort to get things done by providing improved performance, minimizing breakdowns and keeping maintenance costs low.