'Azipod' Azimuth Thruster for large capacity arctic transport ship with high ice category Arc7. Ensuring of operability and operating strength under severe ice conditions

摘要

Intensive development of the Arctic shelf and icebreaker fleet are in the progress now. Nowadays large capacity arctic ships are being designed to provide effective transportation of hydrocarbons from the Arctic shelf. These ships will operate without icebreaker assistance under severe ice conditions. The type of this ships is pushing-pulling i.e. both ahead and astern modes can be used in ice covered waters. However, astern mode is used for navigating under severe ice conditions. It is planned to fit these ships with high power AZIPOD Azimuth thrusters to achieve the highest operating efficiency. Assurance of Azimuth thruster reliability is one of the most important problems within the framework of designing of modern large capacity arctic ships. This paper describes modern methods and results concerning the assurance of operating strength of 15MW AZIPOD for large capacity pushing-pulling tanker with category Arc7. Pushing-pulling ice ship has moderate ice bow and can move both ahead and astern under ice conditions. The calls at Siberian river mouths with fresh ice of a higher strength are the typical operational conditions for this ship. The main principles of the assigning of ice strengthening on main elements in line of force as well as ice loads acting on the propeller and AZIPOD elements are considered in this paper. The main results concerning the assurance of operability of main electrical engine are presented as well.