Page 30: of Maritime Reporter Magazine (December 1998)

GREAT SHIPS OF 1998

Shipbuilder

Vessel name

Vessel type

Owner/Operator

Daewoo Heavy Industries Ltd.

Loch Rannoch

Shuttle tanker

Maersk Company Ltd.

By the very nature of their operating environ- ment, and the long-term expectations of their users, new-generation shuttle tankers rank among the toughest yet most technically refined vessels, designed to ensure uninterrupted service in arduous conditions. Signaling the entry of both the A P Moller Group and BP Shipping to the shut- tle tanker sector, the 130,000-dwt Loch Rannoch has been designed and constructed for a 40-year life in waters as rigorous as those encountered west of Shetland in the north-east Atlantic. BP

Shipping will operate the vessel on behalf of BP

Exploration, which has fixed her for an initial seven-year term from disponent owner A P

Moller's Maersk Company.

Exhaustive attention to structural strength and reliability, state-of-the-art finite element model- ing, the incorporation of significant margins in the scantlings, and the adoption of a highly compart- mentalized hull configuration has been comple- mented by the application of the full redundancy principle to her propulsion and associated sys- tems.

Delivered ahead of schedule and within budget by Daewoo Heavy Industries, Loch Rannoch has been assigned to continuous-cycle duties lifting crude oil in 850,000-barrel lots from the

Schiehallion floating production, storage and offloading (FPSO) vessel to the Sullom Voe termi- nal on Shetland, some 150-km to the east. On the

European offshore oil industry's Atlantic frontier,

Schiehallion poses considerable demands on pro- duction and transportation by virtue of the harsh weather and sea conditions prevailing for much of the year. Indicative of what can be expected in operation, the design criteria for the tanker's dynamic positioning (DP) performance and bow loading arrangements have been based on a sig- nificant wave height of 6-m, compared with 4.5-m for similar-capacity vessels deployed in the North

Sea. The forecastle and bow mooring deck height including bulwark has been raised by 3-m relative

Loch Rannoch

Main Particulars

Designer Daewoo Heavy Industries Ltd.

Country Korea

Flag United Kingdom

Classification society LR

Contract date November 1996

Launch date March 1998

Delivery dote August 1998

Length, o.a 884.5 ft. (269.6 m)

Length, b.p 840 ft. (256 m)

Breadth, molded 151ft. (46 m)

Depth, molded 73.5 ft. (22.4 m)

Width of double-skin, side 9.7 ft. (2.96 m)

Width of double-skin, bottom .. .10.5 ft. (3.2 m)

GT 75,526

Lightweight 26,220.5 tons

DWT, design 127,259.7

DWT, summer 130,031.1

Draft, design 50.5 ft. (15.4 m)

Draft, summer 51.2 ft. (15.6 m)

Speed, service (85% MCR) 15.5 knots

Speed, service (alternative engine rating) 14.3 knots (78% MCR with 20% SM)

Cargo capacity (liquid) 138,381 cu. m.

Bunkers, heavy oil 3,078 cu. m.

Bunkers, diesel oil 294 cu. m.

Water ballast 60,713 cu. m.

Main engine Mftr. ... .Korea Heavy Industries Co.

Main engine B&W 7S50 MC

CP Propellers Ulstein

Diesel-driven engine Ssang Yong

Diesel-driven alternator Nishishiba

Boilers Mitsubishi

Danes Hagglunds

Mooring equipment Kock

Coating IPK

Cargo pumps Kvaerner

Cargo control system Norcontrol

Ballast control system Norcontrol

Complement . . .officers - 22; crew -11; spare - 6

Rudder Schilling

Bow thruster Ulstein

Stern thruster Ulstei

Bridge control systems Norcontrol

Fire detection system Consilium

FiFi system Namyang

Radars Norcontrol

Sat/Nav SAIT

Loran-C Furuno

GPS, DGPS Norcontrol

Computer Del

Incinerator Teamtec

Waste compactor Metos

Woste shredder Meto

Sewage plant Taiko to that which would be deemed necessary for the North Sea, which itself can be treacher- ous at times. A fre- quently large angle of divergence between wind and waves, a char- acteristic of conditions in the waters west of

Shetland, has necessi- tated particular atten- tion to the DP engineer- ing design, given the implications for uptake operations based on the shuttle tanker maneu- vering and lying abaft the FPSO.

Two low-speed MAN

B&W diesels, located in separate engine rooms, and driving twin

Ulstein controllable pitch propellers, with twin Schilling high-lift rudders, gives form to the redundancy concept which infuses the design. In fact, long- term risk management thinking pervades every aspect of the tech- nical project. One expression of this has been the failure mode and effect analysis carried out on the DP system by Lloyd's Register, to which classification of the tanker has been entrusted. The exercise was undertaken to help ensure that no single failure would lead to greater than 50 percent loss of DP capability, in accordance with the DP (AA) nota- tion.

Besides two huge thrusters of 2.5-MW apiece located in 3-m diameter tunnels in the bow, Loch

Rannoch has an 800-kW tunnel thrust unit built into each skeg. DP (AA) confirms that her hydro- dynamic system with automatic control is capable of moving, maneuvering and holding the desired heading and position of the ship, and that power, control, thruster and other systems pertinent to the DPS have been configured so that a fault should not result in loss of position. For such tankers, loss of position or deviation of course while on station or when approaching or departing the offshore unit could have serious consequences, from a cessation of offloading to collision.

Loch Rannoch is a remarkable ship in many respects, and her environmental features reflect not only the sensitivities of the communities bounding her trading domain, but also the corpo- rate disposition of both BP and A P Moller. For instance, the relative narrowness of her center tanks, and the closed-loop vapor recovery system employed when transferring cargo from the FPSO, mirror a concern with minimizing the generation of volatile organic compounds (VOCs).

Circle 26 on Reader Service Card

Shipyard

Vessel name

Vessel type

Owner/operator

Azov Sea

DH Oil and Chemical Tanker

Valloy Shipping Co.

Built by Croatia's Shipyard Trogir,

Azov Sea is the fourth in a series of nine 47,400-dwt double hull IMO 3 oil and chemical tankers contracted with

Shipyard Trogir and two other Croatian shipyards, Split and Uljanik. The entire series is due for delivery by the end of 1999. Azov Sea and its sisterships are a direct result of more than 10 years research and expe- rience by Shipyard

Trogir in the area of double hull designs.

The ship is pow- ered by an MAN

B&W - Brodosplit 6S50MC Mark VI main engine, which develops 8,310 kW at 123 rpm.

Circle 27 on Reader Service Card

Azov Sea

Main Particulars

Designer Shipyard Trogir is. Co.

Flag Liberia

Classification LR+100A1

Delivery dote March 1998

Length, o.a 598.7 ft. (182.5 m)

Length, b.p 573.4 ft. (174.8 m)

Breadth, molded 105.6 ft. (32.2 m)

Depth, molded to main deck 57.4 ft. (17.5 m)

Draft, design 36 ft. (11m)

Draft, scantling 40 ft. (12.2 m)

GT 27,526

Displacement 57,054 m.t.

DWT, design 41,154 m.t.

DWT, scantling 47,374 m.t.

LWT 9,680 m.t.

Speed, trial (90% lood) 15.4 knots

Complement 28

Cargo capacity 53,038 cu. m. cargo tanks + 1,260 cu. m. slop tanks

Water ballast 21,160 cu. m.

Bunker 1,735 cu. m. % high tensile steel 2.5

Main engine Brodosplit - MAN B&W 6S50 MC Mark VI

Output 8,310 kW at 123 rpm

Propeller Kamewa

Generators Ul[anik-Tesu

Generator engines MaK

Emergency generator Oemp-MAN

Motor starter Koncar-Elektrolux

Couplings Flange

Engine controls UMS

Steering controls Porsgrunn

Bearings Blohm+Voss

Coatings Sigma

VHF radio Furuno

SSB radio

SATNAV Furun

Radar Kelvin Hughes

Compass Anschiitz

GPS Trimble

Autopilot Anschiit

Pumps Frank Mohn

Air conditioning Sabro life boats Grebe

Davits

FiFi system Unitor

Waste management Teamtec-Gola

Desalination equipment Aifa Laval

Cargo control system Saab

Ballast control system

Cargo hoses handling crane Radez/Nor Marine 30