Decision making in cargo tank coatings for chemical tanker companies

Abstract

To choose the most effective tank coating is critical issue prior to ship construction for chemical tanker companies. Several criterias according to goals of companies are considered. First application as cost and difficulty, cargo compatibility, cargo tank cleaning, maintenance, durability, freight income and usage life time of cargo tank coating are the criterias to decide the tank coating which is one of epoxy, zinc, stainless steel and MarineLine. In this context, the aim of this study is to decide which tank is most effective as priceperformance. According to this aim, the ratings of alternatives for tank coating have been researched and scored among these tank coatings in comparison with their specifications by three tank coating experts. And the importance weights of these criterias to choose a tank coating prior to ship construction have been asked to 15 operation managers of chemical tanker companies that these companies consist eighty percent of whole chemical tanker market in Turkey. 15 decision makers have scored the importance weights of the criterias with linguistic expressions. The ratings of alternatives and the average of importance weights of 7 criterias have been evaluated by fuzzy TOPSIS method. In results of the calculations, coefficients of 4 cargo tank coatings are 0.27 (epoxy), 0.22 (zinc), 0.38 (stainless steel), 0.35 (MarineLine). According to calculated coefficients, stainless steel cargo tank coating is the most effective tank coating when the 7 criterias are considered together. Although the stainless steel cargo tank coating has highest value, the difference between stainless steel and MarineLine is so less in comparison with the other cargo tank coatings. The reason of nuance is the fact that the first application cost of MarineLine cargo tank coating is much less than stainless steel cargo tank coating and MarineLine cargo tank coating is as well as stainless steel in terms of cargo compatibility. © 2017 Nikola Vaptsarov Naval Academy - Varna, Bulgaria.