Design of an icebreaker Offshore Service Vessel (OSV) of 80-m in length might seems a fair step up from a 30-m harbour tugboat, but all in a day’s work for Robert Allan’s Vancouver-based versatile naval architects, who have just been awarded a contract for two new designs for such vessels to be built in Turkey for operation in the shallow, seasonally ice-bound waters of the Caspian Sea.
TundRA 8000 OSV Preliminary Design: Image courtesy of Robert Allan
Robert Allan Ltd. is an independent, privately owned firm of Consulting Naval Architects founded in 1930 when Robert Allan commenced private practice as a Consulting Naval Architect. Year on year, just like Topsy the business grew and grew until in 2008 the company was restructured to a culture of employee ownership with eleven of Robert Allan Ltd.'s core group of senior employees becoming shareholders in the firm. But a present generation Allan – Robert G. – grandson of the founder, remains Executive Chairman and is still actively involved in day-to-day operations of the company which is now a leader in commercial specialised craft design.
In the meantime, the Robert Allan AVT 3000-class Voith Schneider tugboat Cabo de la Vela has arrived in Columbia after the long delivery voyage from the Uzmar Tug and Work Boat Factory in Izmit, also in Turkey.
This tugboat is the second of a two boat order from Carbones del Cerrejón and she will join her sister Media Luna for operations in Columbia’s Puerto de Bolivar, one of the largest coal loading ports in South America, where with a 60-tonne bollard pull, the pair will be the most powerful tugs on station.
Tugboat 'Cabo de la Vela': Photo credit Robert Allan
The 30.75-m Cabo de la Vela, like most power-packed tugs of this type has a relatively deep draft of 6.2-m, and is equipped with a pair of General Electric 12V228 diesel engines, each rated 2289 KW at 1050 rpm, with each unit driving a Voith Schneider 30R5-250 cycloidal propeller for tight manoeuvring.
The well-proven GE V228 engines are high-compression, four-stroke, medium-speed, turbocharged, electronically fuel injected, class-approved engines designed and built for rigorous marine applications; according to GE capable of operating cost-effectively for more than 20 years. Most components can go without overhaul for up to 40,000 hours on a typical marine duty cycle. This engine delivers economic fuel and lube oil consumption with exhaust gas emissions in compliance with MARPOL Annex VI and U.S. EPA Marine Tier 1 and Tier 2 requirements.
General Electric 12V228 Diesel Engine: Image courtesy of General Electric
The electrical plant comprises two identical Caterpillar C 6.6 ACERT diesel gensets, each with a power output of 125 ekW, 60 Hz, 480V, and Caterpillar have also supplied a 546 KW @ 1800 RPM Caterpillar C18 ACERT auxiliary diesel engine to drive a Fire Fighting Systems SFP 250x350 XP horizontal centrifugal pump.
On deck, winch hydraulics are powered off the front of the FIFI pump engine with a back-up electro-hydraulic pump-set for emergency use and maintenance. The aft deck machinery includes a Rolls Royce ATWH 1500/200 render-recover hawser/towing winch with horizontal warping head, and on the foredeck is a Rolls Royce AW20.5U2H anchor windlass with two cable lifters and two horizontal warping heads.
On trials the Cabo de la Vela met or exceeded all performance expectations including a free-running speed of 13.1 knots. Now Robert Allan’s naval architects turn their attention to the design of those icebreaking OSV’s.