Two of BHP Billiton’s new six vessel fleet of RAstar85 azimuthing stern drive (ASD) tractor tugs have begun initial operations in Port Hedland, Australia. Operated by Rivtow Marine, they will support the world’s largest bulk tonnage export port.
Built by ASL Shipyard in Singapore, the vessel and deck machinery designs were the result of close cooperation between the design teams at Robert Allan Ltd. and Markey Machinery.
All of the tugs are equipped with specially configured Markey DESF-48-400HP electric hawser winches. Port Hedland presents unique challenges due to its remote location and harsh weather conditions.
Blowing dust and salt are extremely detrimental to machine gearing, which is why these winches feature water-tight enclosed housings and oil-bathed gearing, as well as an enclosed fairlead diamond screw.
Safely escorting barges and ships through the narrow channel of Port Hedland requires significant power and line control. The water-cooled electric motor, drive, and brake of the two-speed winch will provide up to 191 tons of barrel-layer line pull in the low speed range, and a braking capacity of 250 tons under all conditions. The under-spooled single drum is sized for 200 meters of 80 mm diameter plasma.
The winch is equipped with “Markey Machinery Render/Recover®” allowing the winch to automatically “render” (pay out) and “recover” (haul in) line at a specific line tension, eliminating line snap, shock loading and allowing “hands-free” control of the winch during tug maneuvers.
Each tug is also outfitted with two VEP-16-40 10HP vertical capstan/windlasses with bitt ratings of 5 ½ tons, and a single wildcat sized for 26mm grade 2 stud link chain.
Founded in 1907, Markey Machinery is the leader in the design and manufacturing of high quality custom deck machinery for workboat, scientific, and dockside applications. Markey products include towing, ship‐ assist, and escort winches; single or multi‐drum and traction‐style deep sea research winches; capstans, windlasses and other high performance machines.
The products and services herein described in this press release are not endorsed by The Maritime Executive.