What is Regulating Valve?

A regulating valve, also known as a control valve, is an automated mechanical device used to control fluid flow by varying the size of the flow passage as directed by a signal from a controller. This enables direct control of flow rate, pressure, temperature, and liquid level in process systems.

Industries & Applications

• Oil & Gas: Pressure regulation in pipelines, refining processes
• Power Generation: Steam control in turbines, feedwater systems
• Chemical Processing: Precise dosing and mixing of chemicals
• Water Treatment: Flow control in filtration and distribution systems
• HVAC Systems: Temperature and pressure regulation
• Pharmaceuticals: Maintaining sterile process conditions
• Food & Beverage: Controlling flow in processing lines

These valves maintain process variables like flow, pressure, and temperature at desired setpoints, ensuring optimal system performance and safety.

Working Principle

Regulating valves operate based on a simple principle:

• A controller compares a process variable measurement to a desired setpoint
• If there's a difference, the controller sends a correction signal to the valve
• An actuator (pneumatic, electric, or hydraulic) moves the valve stem
• The valve's closing element (plug, ball, or disc) changes position
• This alters the flow area, adjusting the fluid flow accordingly
• The process variable moves toward the setpoint value

Common Types of Regulating Valves

• Globe Valves: Excellent for throttling, precise control
• Butterfly Valves: Compact, good for large flow capacities
• Ball Valves: Quick operation, tight shut-off
• Diaphragm Valves: Good for slurries and corrosive fluids
• Pinch Valves: Ideal for abrasive and slurry applications

Construction Materials

Materials are selected based on the fluid properties, pressure, and temperature:

• Body Materials: Stainless steel, carbon steel, brass, bronze, PVC, alloy metals
• Trim Components: Often hardened materials or alloys for wear resistance
• Seats & Seals: PTFE, graphite, elastomers (Viton, EPDM, NBR), metal alloys
• Stems: Typically stainless steel for corrosion resistance and strength