Pneumatic valve

‌气动侧装式偏心半球阀是一种特殊类型的控制阀门，通常用于流体控制系统中。这种阀门的设计基于半球形阀体，其中阀芯或阀球具有偏心的形状，即球心不在球体的中心。这种设计可用于调节流体的流量，通过改变阀球的位置来控制流体通过阀门的开启程度。这种设计通常用于需要精确控制的应用，例如调节液体或气体的流量。气动侧装式偏心半球阀通过气动装置（例如气动执行器）来控制阀球的位置。‌

‌一、结构描述‌

The valve adopts an eccentric hemispherical valve structure, driven by a double acting pneumatic actuator and integrated with an electromagnetic valve for precise control. Its core components include:

• ‌阀体‌Eccentric hemispherical design, utilizing asymmetric valve core structure to reduce opening and closing torque and minimize sealing surface wear.
• ‌阀座‌Linear sealing contact is formed with the hemispherical valve core, and the sealing surface adopts an elastic compensation structure to adapt to changes in medium pressure.
• ‌气动执行器‌Double acting cylinder design, driven by compressed air to achieve bidirectional 90 ° rotation of the valve stem, supporting on/off or proportional adjustment.
• ‌电磁阀‌As an air path control unit, it receives electrical signals to switch the direction of the air source, ensuring fast response of the actuator.

‌二、设计依据‌

1. ‌流体特性‌Suitable for water, steam, oil and weakly corrosive media, with a working temperature range of -20 ℃~180 ℃ (adjusted according to the sealing material).
2. ‌压力等级‌Compliant with PN16~PN40 (national standard GB/T 12238) or Class 150~300 (American standard API 609).
3. ‌驱动需求‌Double acting actuators require a gas source pressure of 0.4~0.7MPa and are compatible with AC220V or DC24V solenoid valve control signals.

‌三、材质配置‌

• ‌阀体/阀盖‌WCB carbon steel, CF8 stainless steel (ASTM A351) or special alloys, suitable for different working conditions.
• ‌半球阀芯‌Surface welding with Stellite 6 alloy or spraying with tungsten carbide to enhance wear resistance.
• ‌阀座密封‌：PTFE、 Enhanced nylon or metal hard seal (suitable for high temperature and high pressure).
• ‌阀杆‌17-4PH stainless steel (ASTM A564), with resistance to torsion and corrosion.
• ‌气动执行器‌Aluminum alloy cylinder body, internal polyamide piston, IP67 protection level (compliant with ISO 5211 standard).

‌四、执行器与电磁阀协同控制‌

• ‌双作用气动执行器‌Valve opening and closing are achieved through bidirectional gas supply, and the current position is maintained when power is cut off, requiring an external reset signal.
• ‌电磁阀选型‌Four way five port structure, embedded pilot electromagnetic control, response time ≤ 50ms, supports manual emergency operation.
• ‌控制模式‌Can be connected to DCS/PLC system to achieve remote switch control or linkage adjustment with flow/pressure sensors.

‌五、执行标准‌

• ‌阀门‌GB/T 12238 (flange type), JB/T 11491 (eccentric structure), API 609 (petrochemical industry).
• ‌气动执行器‌ISO 5211 (installation interface), EN 15714-3 (safety of pneumatic components).
• ‌电磁阀‌IEC 60534-8-3 (Industrial Automation Control Standard).
• ‌密封测试‌GB/T 13927 (Shell Test and Sealing Test), leakage level up to Class VI (Soft Seal) or Class IV (Metal Seal).

‌六、应用优势‌

• ‌高效密封‌Eccentric structure reduces friction, extends service life, and has a sealing leakage rate of ≤ 10ppm.
• ‌快速响应‌The pneumatic actuator is matched with the solenoid valve, and the full stroke action time is ≤ 3 seconds (depending on the diameter).
• ‌维护便捷‌Modular design supports online replacement of valve seats and seals, reducing downtime.