Triyards has built four RAstar escort and offshore terminal tugs for Star Marine, to operate in the port of Rabigh in Saudi Arabia
Saudi Arabia-based Star Marine has expanded its Red Sea fleet with four new escort tugs. These will be stationed in the port of Rabigh in Saudi Arabia and managed by Marine Services Co.
Murjan 1, 2, 3, and 4 are RAstar 3400 design escort and offshore terminal support tugs, built by Triyards’ shipbuilding facility in Saigon, Vietnam, on contract to Greenbay Marine Services. They were designed by Canada-based Robert Allan and classed by Bureau Veritas for unrestricted navigation.
These are 34 m azimuthing stern drive tugs with sponsoned hullforms developed exclusively by Robert Allan. Designed using computerised fluid dynamics, the hullforms underwent model and full-scale testing.
Robert Allan said the hullforms provide “significantly enhanced escort towing and seakeeping performance” due to the sponsons and prominent foil-shaped escort skeg forward elements. “This combination enhances escort forces and reduces roll motions and accelerations to less than half those of comparable sized standard wall-sided tug hulls,” said Robert Allan.
Murjan 1 has a mounded beam of 13.5 m and moulded hull depth of 6.18 m to the bottom of the skeg with a maximum draught of 5.7 m. During sea trials this tug achieved a free running speed ahead of 14.1 knots, forward bollard pull of 73.8 tonnes and astern bollard pull of 71.5 tonnes. The other tugs have similar features and performance.
Their main propulsion comprises a pair of Wartsila 8L26 diesel engines, each rated for 2,610 kW at 1,000 rpm. These drive Schottel SRP 1515 controllable pitch azimuth-drives. Onboard electricity is generated from two MAN diesel gensets, each with a power output of 300 ekW.
Murjan tugs can receive power at 100 A from shore distribution and have a harbour generator with a power output of up to 140 ekW. They have fully automated switchboards in air-conditioned control rooms and hydraulic power units to drive deck machinery.
Each tug has a pair of DMT winches – a double-drum ship-assist and escort synthetic hawser winch on the forward deck and a single-drum towing winch fitted with 850 m of steel wire rope, on the aft deck.
Two of these tugs have a Palfinger knuckle-boom crane installed on the port side, with a lifting capacity of 10 tonnes at 4 m. The other two tugs have pedestals fitted ready for a crane installation of up to 49 tonnes.
Tug fenders have been arranged for specific operations at Red Sea terminals. Each tug is fitted with a streamlined 480 mm x 300 mm W fender for handling low freeboard coastal vessels and oil barges.
Each tug also has a cylindrical fender on the bow, augmented by a W fender below. They have 300 mm x 300 mm hollow D fenders that provide protection at the water line and a W fender at the stern.
Wheelhouses on the tugs were designed for all-round visibility with a forward control station. Accommodation was built for operations in Middle East environmental conditions. There is air conditioning and capacity for up to 10 crew with single cabins for the master and chief engineer, plus two more single cabins and three double cabins.
The tugs were also built for tackling marine and port emergencies, with FiFi 1 fire-fighting systems with additional drenching and foam systems. They also have equipment for supporting an oil spill response, a SOLAS rigid-hull rescue boat and life rafts and a hydrogen sulphide gas detection system. They can store 180 m3 of fuel oil, 70 m3 of potable water, 20 m3 of foam and 20 m3 of dispersant.
The port of Rabigh mainly deals with crude and oil products, including liquids and polymers. There is an oil terminal with a quayside depth of 23 m linked to a refinery and petrochemical plant. There is also a cargo quay for container shipments with an anchorage depth of 11 m to 12.2 m
Murjan 1 particulars:
Owner: Star Marine
Manager: Marine Services Co
Operation area: Red Sea
Builder: Triyards SSY
Designer: Robert Allan
Classification: Bureau Veritas
Design: RAstar 3400
Length, oa: 34 m
Beam, moulded: 13.5 m
Maximum draught: 5.7 m
Bollard pull: 73.8 tonnes
Free running speed: 14.1 knots
Main engines: 2 x Wartsila 8L26
Propulsion: 2 x Schottel SRP 1515 drives