Control valves regulate flow, pressure, temperature and level in industrial process pipelines. A correctly selected control valve improves process stability, reduces energy loss and protects downstream equipment. A poorly selected valve may cause noise, vibration, leakage, hunting, cavitation or poor control accuracy.
Key Data Required for Control Valve Selection
| Data Item | Why It Matters |
|---|---|
| Medium | Determines material, trim design and sealing choice. |
| Flow rate | Used for Cv/Kv calculation and valve sizing. |
| Inlet and outlet pressure | Determines pressure drop, cavitation and noise risk. |
| Temperature | Affects body material, packing and actuator selection. |
| Control signal | Determines positioner, actuator and control system interface. |
Valve Body Type Selection
Globe control valves are widely used for accurate throttling in chemical, steam, water and gas systems. Ball valves and butterfly valves are often selected for larger pipelines, lower pressure drop and on-off or modulating service. Eccentric rotary valves can be suitable for slurry, dirty media or applications requiring good shutoff with rotary motion.
Actuator and Positioner Selection
Pneumatic actuators are common in process plants because they are reliable, fast and suitable for hazardous areas. Electric actuators may be preferred when compressed air is unavailable or when digital control is required. A smart positioner can improve valve response, diagnostics and communication with the control system.
Common Sizing Mistakes
- Selecting valve size only by pipeline size instead of calculated Cv/Kv.
- Ignoring minimum flow condition and controllable range.
- Using unsuitable trim for high pressure drop service.
- Ignoring cavitation, flashing, noise and vibration risk.
- Choosing body or seal material without checking medium compatibility.
Santan Fluid Support
Santan Fluid supports control valve selection for chemical, petrochemical, water, steam, oil and gas pipeline systems. We help customers compare Samson, SHANGYI, CHUANYI and other control valve solutions with suitable actuators, positioners and accessories.
Need Technical Selection Support?
Send your process medium, pipe size, pressure, temperature, signal requirement and model reference to sales@santanfluid.com, or contact Santan Fluid by WhatsApp +86 136 9022 318.