Eccentric rotary valves are suitable for equipment in thermal power plants

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　　The eccentric rotary valve, also known as a cam-deflected valve, operates on the principle of an eccentrically rotating sectorial ball valve; the eccentric spherical crown comes into contact with the valve seat, and when it opens, the ball core separates from the valve seat； When closed, the ball core gradually makes contact with the valve seat, exerting a compressive force on it. 　　The body of a conventional eccentric rotary valve consists of a long-neck wafer-type valve body, a valve disc in the form of an arcuate spheroid or hemispherical crown, a valve seat, a retaining ring, valve stems (primary and secondary), guide sleeves, and packing. There is a single type of parts, and no standardization, serialization, or modularization among different specifications; it is merely a simple combination of parts. Based on the concepts and ideas put forward by the \"concept valve,\" the eccentric rotating concept valve allows for the grouping and classification of key components during valve design, taking into account requirements regarding sealing performance or the impact of operating conditions on materials; a modular product database is established, and separate component modules are created according to the characteristics of products with different requirements. 　　Since the eccentric rotary valve regulates and shuts off the medium through the rotation of an eccentric valve disc, it combines the advantages of ball valves and butterfly valves. It has a low leakage rate, can also function as a shut-off valve, features a large adjustable ratio, is small in size and light in weight, has a high flow coefficient and high dynamic stability. The valve effect (a phenomenon in which the flow characteristic curve of ordinary valves becomes distorted at the critical point) is not significant, and the unbalanced force on the valve disc is low (about 1/2 that of single-seat valves). It is suitable for a wide range of temperatures and has good versatility. To change the flow capacity of a valve of the same specification, it is sufficient to replace the valve seat without needing to replace the valve disc. The inner cavity of the valve has a simple structure, making it easy to apply linings to meet the requirements of different media. This valve boasts excellent overall performance and can replace conventional control valves; it is particularly suitable for applications that require a wide range of regulation (in such cases it can substitute for one large valve or two smaller valves connected in parallel, thereby simplifying the system and control). It also features high flow capacity and low resistance. Such as the steam heating control valves and main condensate control valves in thermal power plants, as well as high-viscosity media (such as heavy oil).