Germans builds Iranian feeders

Six 2,478 TEU feeder boxships ordered by Islamic Republic of Iran Shipping Lines (IRISL) will be equipped with MacGregor hatch covers with a partial box design offering improved construction, maintenance, and operational characteristics. The Tehran-based owner has ordered the MTW 2500 type containerships from Norway’s Aker Kvaerner Yards group, which has allocated four ships to its MTW yard (AMTW) in Wismar, and two ships to its Kvaerner Warnow Werft (KWW) in Rostock-Warnemünde.

The newbuildings will have a length of 207.4m, a beam of 29.8m, a deadweight of 33,825 tonnes and will each feature 200 reefer sockets. Each ship will be equipped with a Sulzer 7RTA72U-B low-speed main engine, having a maximum continuous power of 21,560kW at 99 rev/min and driving a single CP propeller. Service speed is 22.3 knots on a design draught of 10.1m.

They will also each be supplied with three Wärtsilä diesel generating sets, two sets with Wärtsilä 8L20 engines each of 1,360kW output at 900 rev/min, and the third set with a Wärtsilä 6L20 engine of 1,020 kW at the same speed. The main engines will be built at Wärtsilä’s Trieste factory in Italy while the generating sets will be manufactured at the Vaasa factory in Finland.

The four ships to be built by AMTW will be delivered between the end of 2003 and middle of 2004, whereas KWW will deliver the two ships in the second quarter of 2004.

Aker Kvaerner Yards claims that the synergies between the two yards have contributed considerably to the success of this tender. It was solely due to the combined resources of AMTW and KWW that the German yards were able to be in a position to complete the series of six containerships by the middle of 2004.

Featuring a partial box-girder design, access to the holds of the 33,900 dwt ships will be arranged by weather tight lift-away covers serving the 10 hatches, each complete outfit totalling 29 panels. MacGregor developed this design to make optimum use of steel materials used in lift-away hatch covers with longitudinal joints. In this type of cover the joint beam area is heavily loaded when a ship heels, but when the ship is upright all beams are loaded equally. This means that the joint beam contains steel material which is effectively redundant for part of the time and the partial box-design enables loads incurred, when the ship is upright, to be transmitted to the same areas as in a heeled situation thus optimising the usage of steel material.

Another advantage is the high quality of painting that can be achieved underneath the cover, accessed through closed top plate stiffeners. This area can be blasted much more effectively compared with the usual angle-bar stiffeners. The dirt-collecting surfaces formed by angle-bar stiffeners are also avoided by the smooth-surface of the partial box construction. These dirt-collecting surfaces can be difficult to see, let alone clean and without cleaning can be a source of corrosion.

Three MacGregor electro-hydraulic GL-2 wire-luffing deck cranes will achieve efficient container handling, as well as removal and replacement of the hatch cover panels. These have lifting capacities ranging from 36t at 29m outreach to 45t at 25m outreach. The 18 cranes commissioned for these MTW 2500-class ships will take the total number of MacGregor cranes in service with IRISL to 122.

This order forms part of an ambitious programme of investment in new tonnage by IRISL which includes a five ship series of 2,188 TEU feeders being built, for the first time, in Iran. By 2005 the company plans to have placed contracts for around 30 newbuildings, including Capesize, Panamax and Handymax class bulk carriers, general cargo and container ships. The new tonnage will help the company to achieve a projected 75 per cent share of Iran’s domestic seabourne container trade. Over 50 per cent of Iranian exports and around 40 per cent of the country’s imports are currently handled by IRISL.