Decidamp DC30 for extreme temperatures in Icebreaker
The challenges
GSHI-COSL 8000HP AHTS ICE-Breaker is a unique vessel manufactured in China and commissioned to operate through ice filled waters and subzero conditions. Icebreakers typically require structural strengthening for protection as they experience impact from ice loads. Operating in extreme weather and temperature conditions, the vessel helps supply channels stay in operation through polar regions. Featuring a strengthened double-hulled, rounded keel, for ice clearing, and extra power to push through sea ice, the ICE-Breaker will safely escort supply vessels throughout the world.
ICE-Breaker required a high performance solution to minimise vibration stress from several sources, damping the harmful energy to reduce risk of any long-term damage.
The specially designed hull to direct broken ice around or under the vessel is essential for safety. With stringent IMO certification requirements to meet, the wide shape is strengthened to resist ice pressure however it can be more prone to slamming. Typical resonant vibration from wave slap spreads through the structure and into accommodation areas. High impact ice cutting activity (ramming, impact, breaking ice) subsequently creates further radiated noise with constant vibration and jarring against the ice. Oscillation of large powerful engines including the ice cutter’s main turbine and strengthened propellers with extra torque add to the challenge on this heavy duty vessel.
The solutions
After thorough analysis, the team of experienced marine engineers from Pyrotek worked with the shipyard to specify and install a high performance system in several areas across a complex design.
The double hull is divided by additional bulkheads to protect in case of holes from ice-ramming activity. Featuring on-board medical facilities, the emergency room ceiling bulkheads required treatment to reduce vibration and structure borne noise in sensitive areas.
Addressing the main engine, generator base vibration as well as thruster body vibration was deemed crucial to protect the structure and the mechanics. Decidamp DC30 was ideal for this application. A polyurethane based damping paste, it works in a constrained layer configuration to provide a high performance, easy to apply, corrosion resistant solution.
The results
The highly effective Decidamp DC30 performed well over the temperature range, and successfully reduced transfer of vibration to a satisfactory level. The system filled the role of specialised protection measures crucial to the structural longevity of the vessel and also worker conditions on board.
The owners were pleased with the results inside the ship when under operation. Solutions installed met the requirements of Safety of Life at Sea (SOLAS) and the International Maritime Organization (IMO) regulations.