In the fluid control systems of industrial production, the precise regulation of medium parameters such as flow rate, pressure, and temperature is crucial. The electric single-seat control valve is one of the key devices to achieve this goal. With its unique structural design and excellent performance, it plays an irreplaceable role in many industrial fields.
The electric single-seat control valve is mainly composed of two parts: an electric actuator and a control valve body. The electric actuator is its "power source", usually using a servo motor as the driving component. It can receive a 4-20mA DC current signal from the control system and convert it into a corresponding mechanical displacement to drive the valve stem to move. The control valve body includes components such as the valve core, valve seat, valve stem, and valve cage. Among them, the valve core and valve seat adopt a single-seat structural design. The valve core is plunger-shaped and forms a precise fit with the valve seat, which is the core of its precise regulation.
Its working principle is based on the gap change between the valve core and the valve seat. When the electric actuator receives a control signal, it will drive the valve stem to drive the valve core to move up and down. When the valve core moves upward, the gap between the valve core and the valve seat increases, the medium flow area becomes larger, and the flow rate increases accordingly; when the valve core moves downward, the gap decreases, the flow area becomes smaller, and the flow rate decreases correspondingly. Through this continuous displacement change, the electric single-seat control valve can accurately control the medium flow rate to meet the flow requirements under different process conditions. At the same time, due to the single-seat structure, the sealing performance between the valve core and the valve seat is good, which can effectively prevent medium leakage when closed.
The electric single-seat control valve has many significant advantages. Firstly, it has high regulation accuracy. Its electric actuator responds quickly and positions accurately. Combined with the precision machining of the valve core and valve seat, it can realize fine regulation of flow rate, with a control accuracy of up to ±1%. It is suitable for occasions with strict requirements on flow control, such as the feed regulation of chemical reaction kettles. Secondly, it has excellent sealing performance. The single-seat structural design concentrates the contact pressure between the valve core and the valve seat, resulting in good sealing effect and small leakage. The leakage level can usually reach ANSI Class IV or higher, which can effectively avoid unnecessary loss of medium and environmental pollution. Moreover, it has a simple and compact structure, small volume, light weight, and is convenient to install and maintain, especially suitable for pipeline systems with limited space. In addition, the electric drive mode makes it easy to integrate with industrial automation control systems, enabling remote control and automatic regulation, reducing manual intervention, and improving production efficiency and safety.
In practical applications, electric single-seat Control Valves are widely used in industries such as petroleum, chemical industry, metallurgy, electric power, and water treatment. In the petroleum refining process, they are often used to control the reflux of distillation towers, ensuring the stability of temperature and pressure in the tower and improving product quality; in chemical production, they can accurately regulate the addition amount of various chemical reagents to ensure the full progress of chemical reactions; in the electric power industry, they are used for flow control in boiler feed water systems to maintain the normal water level and steam output of the boiler; in the field of water treatment, they can regulate the chemical flow of dosing devices to ensure that the water quality meets the standards. With the continuous improvement of industrial automation, electric single-seat control valves are also continuously upgraded and improved. The new type of electric single-seat control valve adopts a more advanced intelligent electric actuator, equipped with high-precision sensors and microprocessors, which can realize functions such as automatic flow calibration, fault diagnosis, and remote communication, further improving the reliability and intelligence level of the equipment. At the same time, in terms of material selection, the valve core and valve seat can be made of wear-resistant and corrosion-resistant alloy materials, such as Stellite and Hastelloy, enabling them to adapt to complex working conditions such as high temperature, high pressure, and strong corrosion.
To sum up, with its precise regulation performance, excellent sealing effect, convenient automatic operation, and wide applicability, the electric single-seat control valve has become an important equipment in the field of industrial fluid control, providing a strong guarantee for the efficient and stable production of various industries.
