Pneumatic Proportional Control Valves

Detailed Information on Pneumatic Proportional Control Valves

Pneumatic proportional control valves are among the most reliable control elements used in industrial processes requiring modulated flow control. Typically featuring a globe valve body design, they work in conjunction with a pneumatic diaphragm actuator and an optional positioner to provide precise positioning between 0–100%. This ensures that process values are kept stable within the desired range.

Operating Principle

• • The air signal from the PLC or control panel is transmitted to the positioner.
• • The positioner calculates the exact amount of air required for the actuator.
• • The actuator moves the valve stem proportionally.
• • The valve opening provides physical modulation between 0% and 100%.
• • Precise position control is achieved through continuous feedback.

Advantages

• • High-precision modulation control.
• • Stable process management and energy efficiency.
• • Ex-proof positioner options suitable for hazardous environments.
• • Body design optimized for steam and high-temperature fluids.
• • Low maintenance requirements and long service life.
• • Reliable pneumatic operation unaffected by power outages.

Material Specifications

• • Body: Cast iron, ductile iron, bronze, or stainless steel
• • Disc: Stainless steel / hardened surface
• • Stem: Stainless steel
• • Seals: PTFE, graphite, high-temperature elastomers
• • Actuator: Diaphragm-type pneumatic actuator
• • Positioner: PN/EX/Smart digital positioner options

Application Areas

• • Modulation control of steam lines
• • Hot water and thermal oil processes
• • Flow / pressure control in chemical process lines
• • HVAC – industrial heating and cooling systems
• • Power plants and boiler applications
• • Food, textile, and petrochemical process automation
• • Precision control in pump bypass and mixing circuits

Technical Specifications

Pneumatic proportional control valves generally feature:
• DN15 – DN300 diameter range
• PN16 – PN40 pressure ratings
• -10°C to +350°C temperature range