The first ammonia dual-fuel large low-speed engine surveyed by China Classification Society (CCS) has successfully completed bench testing and been delivered at the Zhuhai factory of Yuchai Marine Power Co., Ltd. This marks a major breakthrough for China's marine ammonia-fueled low-speed engines, advancing from technical validation to engineering and commercial delivery. It also represents another solid step forward for CCS in the development of green energy power survey technologies.

This engine model, independently developed by China State Shipbuilding Corporation's WinGD, is designated as 6X52DF-A-1.0, with a bore diameter of 520 mm and a rated power of 7470 kW. It adopts high-pressure direct liquid ammonia injection technology, enabling flexible switching between ammonia fuel and diesel modes, with dynamic performance comparable to conventional diesel engines. Equipped with an HPSCR exhaust after-treatment system, it meets the IMO Tier III emission standards and achieves zero carbon dioxide emissions in ammonia fuel mode. This engine, having undergone comprehensive verification by CCS, will be installed on the 25,000 m³ LPG/ammonia carrier of Tianjin Southwest Maritime Co., Ltd., which is classed solely with CCS.

During the project, CCS set up a dedicated service team to provide continuous tracking support, offering strong professional assistance in technical preparation, certification planning, drawing review, component survey, and on-site test verification. The team collaborated efficiently with all parties to drive breakthroughs in key technologies with positive results. On-site surveyors from CCS Guangzhou Branch made multiple trips to Zhuhai Yuchai, Huangpu Wenchong, and other units for technical coordination and exchange, participating throughout the entire process of technical verification, performance evaluation, and type testing. They conducted comprehensive checks on the engine's safety, operability, reliability, and stability, confirming that all test items were successfully completed and that core indicators reached internationally leading levels, thereby providing a solid guarantee for the smooth delivery of the engine.

The successful testing and delivery of this ammonia dual-fuel engine marks an important milestone in the development of China's green marine power equipment. Amid the global trend of marine power transitioning toward low-carbon and zero-carbon solutions, CCS offers reliable support and safety assurance for the green transformation of global marine power through professional technical services and full-process quality guarantees.