A year after PSA Marine, Singapore took
delivery of Rubicon, its first ever RAmparts 3200CL tug from Cheoy Lee Shipyards
, Hong Kong in December 2013, the same builder has now put four more similar tugs, OLNG Sur, OLNG Seeb, OLNG Masirah and OLNG Muttrah into the hands of PSA Marine Qalhat SAOC. These tugs are similar to their predecessors in this design series, with modifications to suit the owner's requirements for operations at the LNG terminal
in the Port of Qalhat in Oman.
OLNG Sur, OLNG Seeb, OLNG Masirah and OLNG Muttrah are RAmparts Series tugs, a series of Z-drive tug designs developed by Robert Allan Ltd, Naval Architects of Vancouver B.C. This particular RAmparts 3200CL design has been developed from a prototype series of vessels, refined for a more shallow draft, and has been constructed by Cheoy Lee Shipyard for numerous Owners. The RAmparts 3200CL design is available in a typical ship-handling configuration with a modest size of skeg, or in an escort configuration with a much deeper skeg for enhanced indirect steering force capability.
Particulars of the OLNG Sur, OLNG Seeb, OLNG Masirah and OLNG Muttrah series of tugs are as follows:
- Length overall - 32 m
- Beam, molded, extreme - 12.4 m
- Depth, molded (hull) - 5.4 m
- Maximum draft - 4.9 m
The tugs were designed and constructed to Lloyd's requirements with the following notation: +100A1 Tug, Fire-Fighting Ship 1 with Water Spray, *IWS, +LMC, UMS, Unrestricted Service
Tank capacities are as follows:
- Fuel oil - 232 m3
- Potable water - 48 m3
- Main engine lube oil - 1.9 m3
- Ballast water - 50 m3
- Foam - 6.9 m3
- Dispersant - 6.9 m3
On trials, the typical performance result for this series of tugs was as follows:
- Bollard pull, ahead - 70 metric tons
- Bollard pull, astern - 65 metric tons
- Free running speed, ahead - 13 knots
The vessel has been outfitted to the high standard for a crew of up to 10 people. The deck machinery comprises a forward hawser/anchor winch, aft towing winch, towing hook and a deck crane.
The lower deck contains four two-crew cabins; a double shower stall lavatory, provision store, laundry and switchboard room. The deckhouse at the main deck level contains two single cabins for the Master and Chief Engineer, a mess/lounge and a fully-equipped galley with refrigerator, stove and spacious cabinets.
The wheelhouse is designed with forward and aft control stations providing maximum visibility to both fore and aft deck working areas.
Main propulsion for each tug comprises a pair of Caterpillar 3516C HD diesel engines; each rated 2,000 kW at 1,600 rpm, and each driving a Schottel SRP 1515 fixed-pitch Z-drive unit, in ASD configuration.
The electrical plant comprises two identical diesel gen-sets, each with a power output of 112 ekW.
Ship-handling fenders at the bow comprise two rows of 800 x 400 OD/ID cylindrical fenders with 480 x 300 mm "W" block type fendering below. Two 300 x 300 hollow "D" fender provides protection at the main and fo'c'sle deck sheer lines, and 500 x 450 mm "W" block type fendering is used at the stern.