ZMA/BP pneumatic diaphragm straight-through single-seated regulating valve is an execution unit for industrial process control, consisting of a multi-spring (or single-spring) pneumatic diaphragm actuator and a straight-through single-seated globe-style valve body. The valve receives pneumatic signals (typically 20-100KPa) or standard analog signals (4-20mA via a positioner) to convert air pressure into linear displacement of the actuator stem, driving the valve stem and plug relative to the seat. By changing the throttling area between the plug and seat, it achieves automated regulation of process parameters such as flow rate, pressure, and temperature. Due to its single-seated sealing structure, this valve features minimal leakage, excellent shut-off performance, and high adjustment precision, making it a classic control device for industries like petroleum, chemicals, metallurgy, and textiles where tight shut-off is required.

Product Image of ZMA/BP Pneumatic Diaphragm Straight-through Single-seated Regulating Valve

1.Superior shut-off sealing:Utilizes a single-seated plug design with a precision-ground seat, ensuring a tight seal when closed. Leakage levels can easily reach ANSI Class IV or the more stringent Class VI (bubble-tight), ideal for processes requiring strict internal leakage control.
2.Classic streamlined valve body:The valve body features an S-pattern flow design with smooth internal cavities, reducing fluid disturbance and pressure drop, thereby providing a high flow coefficient (Kv value).
3.High-precision regulation:The plug profile is precision-engineered based on fluid dynamics to provide linear or equal percentage flow characteristics. When used with an electro-pneumatic positioner, it achieves high-sensitivity proportional adjustment and rapid dynamic response.
4.Robust and mature structure:Adopts a top-guided structure with a large guiding area for high stability. The valve stem is quenched or surface-hardened for excellent wear resistance and mechanical vibration endurance.
5.Flexible drive modes:Equipped with high-performance pneumatic diaphragm actuators, offering simple and reliable operation. "Air-to-open" (ZMA, fail-closed) or "Air-to-close" (ZMB, fail-open) configurations are available based on safety requirements.
6.Intrinsic explosion-proof safety:The adjustment process is driven by compressed air without electrical spark risks, providing inherent explosion-proof attributes suitable for flammable, explosive, and harsh industrial environments.
7.Various bonnet options:Standard, extended (radiator type), or bellows-sealed bonnets can be selected based on medium temperature to protect the diaphragm from heat or prevent leakage of toxic media.
8.Convenient and economical maintenance:Features few internal components and high standardization. The single-plug structure allows for direct disassembly, cleaning, and seal replacement, significantly reducing long-term maintenance costs.

Structural Drawing of ZMA/BP Pneumatic Diaphragm Straight-through Single-seated Regulating Valve

List of Component Names and Materials

Performance Specification Sheet

Standard requirements for external dimensions

1. The structural length of the valve shall comply with the standard of GB/T12221

2. Connecting flanges according to GB/T17241.6 standard

Outline dimension table(Unit: mm)

Notes:

(1) The values in this table are based on PN1.6.

(2) The height with the handwheel mechanism should be increased by 150mm（DN20～50）、180mm（DN65～100）、250mm（DN125～200）、280mm（DN250～300）

Due to the rapid R&D iteration speed of valve products from China Kaivex Valve Group Co., Ltd., the above technical parameters and specification documents, including product overview, features, parts materials, outline dimension charts, CAD drawings, and product instruction manuals, are for your reference only. For actual applications, please contact our valve sales engineers to obtain the support you need for free. Thank you!