A floating liquefied natural gas (FLNG) production and storage vessel operating off the coast of West Africa required 12 large-scale, custom-designed hydraulic cylinders for its mooring tensioner system. These cylinders play a critical role in maintaining vessel stability under harsh offshore conditions. The client needed a partner with proven expertise in designing and delivering large-diameter hydraulic cylinders capable of operating for decades in highly corrosive marine environments. Yongjian was selected for its extensive experience, technical capabilities, and commitment to customized hydraulic solutions. The FLNG system required horizontally installed cylinders with large strokes and built-in accumulators, operating at a working pressure of 230 bar. These cylinders had to withstand: Continuous exposure to seawater Impact from floating debris and offshore equipment Sand and dust carried by ocean winds 30+ years of operation without major failure Each cylinder featured: The coatin