【Ten Years of Rapid Development in Chemical Processing Equipment】Safety valves for the tops of large LNG storage tanks from 1987 to 2023

Is manufacturing safety valves that difficult too?

　On March 16-17, 2023, the China General Machinery Industry Association organized a demonstration test session in Hangzhou for the prototype of the \"Large-scale LNG storage tank roof safety valve (pilot-operated safety valve + vacuum safety valve)\\", which was developed jointly by Ouchuangge Valve Co., Ltd., the Beijing branch of China Global Engineering Co., Ltd., and Zhejiang Zheneng Liuheng LNG Co., Ltd. The appraisal meeting was chaired by Huang Li, President of the China General Machinery Industry Association. Sui Yongbin, former Chief Engineer of the China Machinery Industry Federation, served as the head of the expert panel for the appraisal. The panel consisted of experts from Hefei General Machinery Research Institute, **Pipeline Network Beihai LNG Company, the Nuclear and Radiation Safety Center of the Ministry of Ecology and Environment, Qingdao LNG Company, **Pipeline Network Group Shenzhen LNG Company, Sinopec Guangzhou Company, China Tianchen Corporation, Hefei University of Technology, **Pipeline Network Group Dalian LNG Company, and Sinopec Tianjin LNG Company. The innovative features of this prototype include: a composite sealing structure for the valve disc of the pilot-operated safety valve, which enhances sealing reliability; a pilot valve structure made up of upper and lower polymer film sheets, along with an external gas guiding structure that features a small strain volume and efficient exhaust, thereby improving the reliability of the valve’s operation; the vacuum safety valve incorporates a dual-sealing structure of foam rubber gaskets and O-rings, which prevents overload on the composite sealing surface and improves its sealing performance under positive pressure. The development unit built the first set of fully automated specialized testing equipment in China, enabling comprehensive performance testing of pilot-operated safety valves and vacuum safety valves. 　　The expert committee believes that the performance indicators of the prototype of the \"large-scale LNG storage tank roof safety valve (pilot-operated safety valve + vacuum safety valve)\\" developed have reached an advanced level comparable to those of international counterparts; in particular, parameters such as setting pressure deviation, sealing performance, full-open discharge capacity, and reset performance are at the international leading level.