In the early 2000,a consortium of Oil and Gas Companies operating the Kashagan,a super-giant oilfield located in the North East of Caspian Sea,Kazakhstan area,embraced the challenge of maritimetransportation in ultra-shallow waters,combined with a 5-months ice season per year and the potential riskof exposure to sour gas as a result of a blowout.The paper will present the ad hoc solution studied,testedand implemented for the first time in the naval architecture literature.A fleet of bespoke vessels was designed,model tested in the ice tanks of internationally recognizedresearch centers,constructed and successfully tested in real scale in the field.For such vessels,uniqueof their type,Classification Societies were involved through all project stages,in order to comprehendthese new technical characteristics,thus issue a new set of Class Rules accordingly.A multidisciplinaryactivity of reverse engineering was performed,involving Environmental,Metocean,Ice Engineering andNaval Architecture teams,starting from the probabilistic forecasted of the ice thickness,its temperature andcorresponding actual tensile strength.Vessels structure and propulsion power were dimensioned as a directconsequence of that,allowed to achieve minimum weight,hence minimum draft.Such approach resulted in the construction of 2 highly specialized prototypes:the Mangystau,an ultra-shallow ice breaker for marine logistics supply chain,capable to break up to 1m level ice and navigate at2.5m draft,as well as and the IBEEV,Ice Breaking Emergency Evacuation Vessel,intended to execute thetask of EER-Emergency Evacuation Response,capable to rescue up to 340 people in ice infested waters,with the presence of an H2S toxic gas cloud.These pioneering vessels continue to support the developmentof the Kashagan oil field today.The novelty of the above is mainly constituted by the nonstandard approach to the problem,exploringfor a new way to apply technology rather than applying an existing one,which resulted in the realizationof vessel prototypes and the publication of new set of Class Rules.
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