Collection of SA-15 Operations Data

(By L .Tsoy, S. Karavanov, Yu. Glebko, N. Barabanov ; INSROP Working Paper No. 107 – 1998)

The work performed in the context of WP5 of INSROP Phase-II on collection and systematisation of data on the experience of the construction and operation in the Arctic of modern large icebreaking cargo ships of the SA-15 type with a dead-weight of 15000 t aims at verifying the results of the mathematical modelling of the merchant shipping on the Northern Sea Route envisaged by the investigations within WP6 and WP8.

Multipurpose icebreaking cargo ships of the SA-15 type were built for the Soviet Union in 1982-1987 at Finnish shipyards Wдrtsilд and Valmet (19 units, type ship - m/s Norilsk). The purpose of these ships is transportation of a wide range of cargoes to the equipped ports of the Arctic throughout the year. They are also adapted to carry out unloading onto the fast ice and have a roll-on roll-off deck with an angled lowered ramp.

When ordering the SA-15 type ships, attention was paid to provide high ice resistance qualities. The feasibility study has shown that these ships should have icebreaking capability not less than 1 m and be built for the ULA category of the USSR Register. Power of the propulsion machinery, propulsion system, principal dimensions, their ratios and the hull shape should provide for virtually independent navigation during the summer period and the effective operation in winter ice conditions under the assistance of powerful icebreakers. The ship's power plant comprises two medium speed main engines with a Valmet-Renk single stage double reduction gear. The maximum continuous power of each engine is 7720 kW. Between the main engine and the reduction gear there are two Voith fluid couplings transferring power to a controllable pitch propeller specially designed for ice conditions by the KaMeWa company and used for the first time in the domestic practice.

In the course of the fulfilment of the present work, consideration was given to different aspects of the operation of the SA-15 type ships in the Russian Arctic including the study of the effect of various ice conditions on the efficiency of the operation of these ships (as to area and season as well as to the tactics of sailing - independently and under the icebreaker support). Full-scale ice trials of ships to be put in operation, data on scientific observations during expedition voyages and on the en-route reports of captains of the Murmansk and Far East Shipping Companies were principal sources of information.

Data on the ice damageability gathered during dock inspection and hull repairs of ships of this type were also examined. As a result of the processing of statistical materials on the propulsion in ice and ice impact strength, data on speeds of the movement of ships of the SA-15 type depending on conditions and modes of navigation in ice were obtained and the compliance of the ice performance of these ships, including the ice class, with the conditions of the year round operation on the Northern Sea Route evaluated.

Gathering, generalisation and analysis of data on the experience of design and operation of icebreaking cargo ships of the SA-15 type permitted to draw the following principal conclusion on the efficiency and compliance of these ships with navigational conditions in ice of arctic seas washing the Russian Federation.

Ice performance of ships of the SA-15 type meet the requirements of their efficiency to operate in ice under the support of powerful nuclear icebreakers all the year round in the western part of the Russian Arctic and during the traditional period of the summer navigation in the eastern area thereof. These ships possess the satisfactory ice propulsion and dimensions matching the ability of nuclear icebreakers of the Arktika type and the sufficient ice strength for navigation under the above conditions. At the same time, bearing in mind the future of the development of cargo traffic in the Arctic on new high latitude routes and during the extended, up to the year round, periods of navigation on traditional routes in the eastern area, the construction of icebreaking ships of the new generation mainly characterised by a higher category of hull ice strengthening will be required. CNIIMF has prepared technical and operational requirements for such ships including recommendations on the hull structure and ice strength. Taking into consideration the international IACS requirements being now developed and the IMO Code on ships navigating in polar waters, new icebreaking cargo ships will have to be of at least PC4 polar class to ensure safe and efficient work under the assistance of powerful icebreakers all the year round over the entire length of the Northern Sea Route.

L .Tsoy, S. Karavanov, Yu. Glebko, N. Barabanov, 1998, Collection of SA-15 Operations Data, INSROP.©