New Spanish Coast Guard vessel has Rolls-Royce design and equipmentVessel & ROV News // January 23, 2007
Don Inda was designed by Rolls-Royce.
The first of two coastal protection vessels has been handed over to Spain’s Maritime Safety Authority SASEMAR.
Don Inda has emergency towing as its main role, and the vessel is equipped with a full range of equipment for recovering oil.
Rolls-Royce has developed the design for these vessels and provided the main equipment. Astilleros Zamakona, based at Santurce-Bilbao, was selected to build the Spanish vessels.
They have the UT-Design type name UT 722 L because they are derived from the anchor handler of the same type number, although they differ from an offshore AHTS in many respects.
The new vessels for SASEMAR have a significant level of installed power and very powerful towing winches. They are, however, flexible enough to take on many other roles including pollution clean-up, escort towing, rescue of ships and their crews, emergency co-ordination, firefighting and salvage.
A primary role is the emergency towing of tankers of unlimited size under adverse conditions. The bollard pull of about 220 tonnes makes these vessels the most powerful coastguard vessels in Europe when it comes to towing.
The UT 722 L design is extremely well proven offshore and was an ideal starting point for the Spanish Authority’s requirements.
Don Inda is 80m long, with a beam of 18m and a draft of up to 6.8m. Hull depth to main deck, however, is considerably larger than the normal UT 722 L at 8.25m.
An important feature is the extremely large tank capacity for recovered oil of approximately 1,730m3. But compared with other vessels with recovered oil capacity, this figure can be multiplied, because an oil/water separation system is built in.
The recovered oil tanks will be filled with about 95 per cent oil and 5 per cent water, the separator discharging water of a cleanliness meeting environmental regulations back to the sea, whereas normally oilrec tanks would contain a mixture of about 50/50 oil and water.
Because the recovered oil may have a high viscosity, all these tanks are heated, enabling oil to subsequently be pumped to another vessel or ashore. This feature means that the SASEMAR vessels can act as pumping stations in the event of a massive oil spill.
Four Bergen eight cylinder B32:40 long stroke engines produce a total of 16,000kW. Two engines are coupled to each propeller shaft turning a CP propeller, and a fire pump is geared to the forward end of the inner engine of each pair.
This propulsion system provides a maximum speed of 17.6 knots and a bollard pull of about 220 tonnes. Depending on the operating mode, either all four engines can be run, or just one on each shaft line.
In addition, there are powerful auxiliary generator sets, and the swing-up azimuth bow thruster has its own independent 736kW diesel engine.
Manoeuvring is enhanced by high lift rudders, twin stern tunnel thrusters and an additional bow tunnel thruster supplementing the azimuth unit.
The vessels are being built to Bureau Veritas Class and have dynamic positioning notation AM/ATR, which corresponds to IMO DP2 standard.
The towing winch on Don Inda is designed to use the full bollard pull capability. This main winch is a two drum hydraulic Rauma Brattvaag unit sized for 83mm wire and capable of pulling 300 tonnes with a 550 tonne brake holding load.
For escort work there is a winch on the foredeck with a 45 tonne pull/250 tonne brake load equipped with synthetic rope towlines. A strongly fendered reinforced bow allows the SASEMAR vessels to push disabled ships.
Deck layout aft is designed to give a clear lead for towlines, but the vessels will be prepared for an A-frame at the stern which can be put aboard when required, for example to undertake salvage of sunken vessels.
A comprehensive range of oil booms and skimming equipment enable Don Inda to clear oil pollution both on the open sea and in more confined waters.
There are two oil booms, one with a 100mm freeboard, the other 600mm freeboard, to enclose oil spills under different sea conditions. Oil can be transferred from the booms by a Transrec 150 system to the recovered oil tanks.
For more confined waters, two 15m long floating arms can be deployed from the ship’s side in a wide vee-shape. The vessel moves through the oil spill, sweeping oil towards the recovery pumps.
Two small craft are carried – a MOB/boarding boat and a 9m craft with a bollard pull of two tonnes mainly intended to tow the oil booms. An oil dispersant system will also be installed.
Don Inda is equipped to FIFI II fire fighting standard with three main water/foam monitors plus a self-drenching system.
Don Inda will be stationed in north west Spain, and with its sister ship will give SASEMAR an enhanced coast protection capability.