Bisso Towboat Co. Inc. announced yesterday it had awarded a contract to Main Iron Works LLC, Houma, La., to begin construction of another 6,008-bhp Tier 4 Coast Guard-inspected ASD tractor tug.
The tug will be nearly identical to the Andrew S, which Main Iron delivered to Bisso in late November 2019. The 6,008-hp Andrew S was the first Tier 4 ASD tractor tug built for use on the Mississippi River. It was also the fourth new ASD tractor tug built by Main Iron Works for New Orleans-based Bisso Towboat in five years.
"We are changing Z-drives from Kongsberg to Schottel, gensets from John Deere 99 kilowatts to Cat 118 kilowatts and will be beefing up, upgrading the fendering system," said Bisso President Scott Slatten.
The tug will feature two Caterpillar 3516E Tier 4F main propulsion engines generating 3,004 bhp each at 1,800 rpm. The engines will drive two Schottel SRP 460 FP azimuthing thrusters with 98.4″-dia. stainless steel propellers in stainless steel nozzles. Estimated bollard pull is 78 tons.
Auxiliary equipment will include a JonRie Series 240 escort winch, Caterpillar C4.4 118-kW generator sets and a full complement of safety, monitoring and electronic equipment.
Tankage includes 30,162 gals. of diesel fuel, 1,442 gals. of lube oil, 1,442 gals. of hydraulic oil, 2,000 gals. of DEF, and 9,538 gals. of potable water.
The new tug will be the fifth ASD tractor tug constructed by Main Iron for Bisso in the past six years. It further enhance Bisso’s position of operating the largest fleet of ASD tractor tugs serving the Mississippi River ship-assistant trade, the company said.
Construction is scheduled to begin in August with delivery expected in early fall 2021.