As a core component of industrial fluid control, valves are classified based on multiple dimensions, including structural principles, actuation methods, pressure ratings, and application scenarios. Scientific classification helps users accurately match operational needs and optimize system design and maintenance efficiency.
By structural form, common types include gate valves, globe valves, ball valves, butterfly valves, check valves, and regulating valves. Gate valves achieve on/off switching through the vertical movement of a gate, offering low flow resistance and easy operation, making them suitable for large-diameter pipelines. Globe valves regulate flow by moving a valve disc along an axis, with easy-to-maintain sealing surfaces, and are often used in medium- and low-pressure pipelines. Ball valves control the medium by rotating a perforated ball 90°, offering rapid opening and closing and reliable sealing, and are widely used in natural gas and chemical industries. Butterfly valves regulate flow by rotating a disc around an axis, offering a compact structure and lower cost, and are commonly found in water treatment and HVAC systems. Check valves utilize the medium's own power to achieve unidirectional flow and prevent backflow; regulating valves dynamically control the opening through an actuator to meet the precise adjustment requirements of process parameters.
Valves can be classified by their actuation method into manual, electric, pneumatic, hydraulic, and electromagnetic valves. Manual valves rely on human operation and are suitable for small-diameter or maintenance scenarios. Electric valves are driven by a motor and are suitable for automated control systems. Pneumatic and hydraulic valves are powered by compressed air or hydraulic oil respectively, featuring fast response and high thrust, and are often used for emergency shut-off or large equipment. Electromagnetic valves are controlled by electromagnetic force and are commonly found in small-diameter pipelines where fluid flow is frequently interrupted.
Based on nominal pressure and temperature rating, valves can be classified into vacuum valves, low-pressure valves, medium-pressure valves, high-pressure valves, and ultra-high-pressure valves. The materials and sealing structures must be selected based on the temperature range. For example, chromium-molybdenum steel or nickel-based alloys are often used in high-temperature and high-pressure conditions, while special toughening treatment is required for low-temperature environments. Furthermore, valves can be classified by connection type into flange connections, threaded connections, welded connections, and clamp connections; different methods affect installation convenience and sealing reliability.
Based on application areas, the industrial sector includes specialized valves for petroleum refining, chemical production, power energy, metallurgy, and environmental engineering, such as corrosion-resistant lined valves, high-temperature and high-pressure power plant valves, and wear-resistant valves for coal chemical industries. The municipal and construction sector focuses on valves for water supply and drainage, HVAC, and fire protection systems, emphasizing sealing performance and durability.
With the development of industrial intelligence, intelligent valves are gradually integrating sensing technology and remote control functions to achieve status monitoring and fault early warning, driving the traditional classification towards a "function + intelligence" approach. A scientific understanding of valve classification systems is a crucial foundation for improving the safety, economy, and sustainability of fluid systems.
