ZMA/BN pneumatic diaphragm straight-through double-seated regulating valve is an industrial process control execution unit composed of a multi-spring pneumatic diaphragm actuator and a straight-through double-seated balanced valve body. The valve receives pneumatic signals from the control system or analog current signals (4-20mA) via a positioner to convert air pressure into linear displacement of the actuator stem, driving the valve stem to move the upper and lower plugs relative to the seats. Due to the double-plug structure, the fluid forces acting on the upper and lower plugs are opposite in direction and similar in magnitude, allowing most of the unbalanced force to be offset. Consequently, this valve features high allowable pressure differential, large flow capacity, and excellent dynamic stability, making it particularly suitable for industrial automation systems with high flow rates, high pressure drops, and relatively relaxed leakage requirements.

Product Image of ZMA/BN  Pneumatic Diaphragm Straight-through Double-seated Regulating Valve

1. Excellent force balance performance:The dual-seat plug design utilizes the principle of mutual cancellation of unbalanced forces generated by the medium pressure on the upper and lower plugs, significantly reducing the required output thrust of the actuator and allowing the valve to easily handle high pressure drop conditions.
2.Significant flow capacity:The straight-through double-port flow path design provides a larger flow coefficient (Kv value) than a single-seated valve of the same nominal diameter, enabling more efficient handling of high-volume industrial fluid delivery.
3.Strong dynamic stability:Due to the minimal unbalanced force, the valve plug experiences low fluid disturbance during regulation, effectively suppressing mechanical vibration and fluid noise for smooth operation.
4.Flexible and safe drive modes:Equipped with high-performance pneumatic diaphragm actuators, the valve can be configured as air-to-open (ZMAN, fail-close) or air-to-close (ZMBN, fail-open) to ensure system safety in the event of air supply failure.
5.Intrinsic explosion-proof safety:The adjustment process is driven by compressed air without electrical sparks, offering inherent safety attributes ideal for petrochemical, gas, and other flammable or explosive environments.
6.Mature and durable structure:Utilizing classic top and side guiding structures, the components offer excellent interchangeability. Precision-machined plugs and seats with various material options can adapt to water, oil, steam, and general corrosive media.
7.Various bonnet types:Standard, extended (radiator type), or bellows-sealed bonnets can be provided based on medium temperature to meet wide temperature ranges and strict sealing requirements for toxic or volatile media.
8.Convenient maintenance:Key internals adopt a standardized design, making disassembly, cleaning, and replacement of wearing parts relatively easy, ensuring long-term continuous operation while reducing comprehensive maintenance costs.