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The development of control valves spans an eighty-year history since the beginning of the 20th century; over this time, ten major categories of control valve products have been developed, along with standalone valves and positioners. The evolution of control valves and regulating valves can be traced as follows: In the 1920s, the original control valves for maintaining constant pressure were introduced. Month 30: The V-type control ball valve, represented by two-seat and single-seat valves with V-shaped notches, was introduced. 1940s: Positioners appeared, and new types of control valves were developed; gate valves, angle valves, butterfly valves, ball valves, etc. came into use. 1950s: Ball valves saw widespread use, and tee valves were introduced to replace two single-seat valves in systems. In the 1960s: Only after a series of innovation initiatives, as well as standardization and normalization of the aforementioned products were carried out domestically, did the country develop a complete range of such products. The seven types of valves that we still use extensively today – single-seat valves, double-seat valves, angle valves, three-way valves, check valves, butterfly valves, and ball valves – are still products from the 1960s era. At this time, the open ocean market saw the introduction of the eighth type of layout control valve—the sleeve valve. 1970s: Another product of a new design approach emerged – the rotary valve (a type of control valve belonging to the ninth category of designs). These temporary sleeve valves are widely used at sea. At the end of the 1970s, the Home Industry Unification Program developed sleeve valves, enabling China to have its own series of sleeve valve products. The 1980s: During the period of reform and opening up, China successfully introduced stem packing devices and control valve technologies, which led to the widespread use of sleeve valves and eccentric rotary valves. In particular, sleeve valves began to replace single- and double-seat valves, and their use became increasingly common. At the end of 1980, another significant development in terms of control valves was the introduction of the Cv3000 model as well as compact control valves. In terms of their design, these valves featured a multi-spring diaphragm actuator instead of a single-spring one; it was a refinement in the valve’s design rather than a complete change. Its key feature is that it reduces the weight and height of the control valve by 30%, while increasing the flow coefficient by 30%. 1990s: The focus for control valves in the 1990s was on reliability, addressing particularly difficult production issues, as well as innovation and improvement. By the end of 1990, Hualin Company introduced the tenth model in its lineup: the all-functional ultra-lightweight valve. Its standout features are breakthroughs in reliability, efficiency, and weight. A breakthrough in terms of functionality – products with comprehensive capabilities; thus, one product can replace those with numerous incomplete functions, simplifying selection, usage, and the variety available ； A breakthrough in terms of weight – 70–80% lighter than the dominant types of valves such as single-seat, double-seat, and sleeve valves, and 40–50% lighter than miniature valves ； A breakthrough in reliability – it addresses various factors that contribute to unreliability in traditional control valves, such as the reliability of sealing, the reliability of positioning, and the reliability of operation. The emergence of this product brought China’s control valve technology and application level up to the advanced level seen at the end of the 1990s ； It is a tremendous breakthrough for the changeover valve ； In particular, electronic all-function ultra-lightweight valves are bound to become the mainstream of control valves in the coming century.