Can Butterfly Valves Be Used for Throttling? A Technical Guide

Butterfly valves are widely used in industrial flow control systems, but a common question arises: Can they effectively handle throttling applications?
The short answer is yes—but with specific conditions. In this guide, we’ll explore how butterfly valves work for throttling, their limitations, and how to choose the right valve design for your needs.

How Butterfly Valves Work for Throttling

Butterfly valves control flow by rotating a disc (or "butterfly") within the pipe. Their throttling capability depends on two factors:

1. Valve Design:

• Concentric (Midline) Valves: Simple and cost-effective, but prone to wear at partial openings. Best for on/off applications.

• Double/Triple Offset Valves: High-performance designs with eccentric discs. These reduce friction, minimize wear, and are ideal for precise throttling (HK60-D-GF Electric Hard Seal Flanged Butterfly Valve).

2. Flow Characteristics:

• The disc's angle (15°–75° open) determines flow rate. Beyond 75°, turbulence increases, risking cavitation.

When to Use Butterfly Valves for Throttling

Butterfly valves excel in these scenarios:
✅ Moderate Pressure & Temperature: Suitable for water, air, and oils below 250°F (120°C).
✅ Large Pipe Sizes: Cost-efficient for diameters over 6 inches.
✅ Frequent Adjustments: Quick operation with low torque (e.g., HVAC systems).

Limitations of Butterfly Valves in Throttling

While versatile, butterfly valves face challenges in:
⚠️ High-Pressure Systems: Extreme pressure drops can cause cavitation, damaging the disc.
⚠️ Precision Control: For <10% open positions, globe valves or V-port ball valves are better.
⚠️ Abrasive Media: Slurries or corrosive fluids accelerate wear without hardened coatings.

Solution:
Our Butterfly Valves use stainless steel discs with PTFE seals to resist wear and cavitation in harsh conditions.

Butterfly Valves vs. Other Throttling Valves

How to Optimize Butterfly Valves for Throttling

1. Avoid Small Openings: Keep disc angles between 20°–70° to minimize turbulence.

2. Upgrade Materials: Use hardened discs (e.g., 316SS) and elastomer seats for abrasive media.

3. Monitor Pressure Drops: Install pressure gauges upstream/downstream to detect cavitation risks.

Pro Tip:
Pair our Butterfly Valves with Smart Actuators for automated, real-time flow adjustments.

FAQs About Butterfly Valves and Throttling

Q: Can I use a butterfly valve for steam throttling?
A: Yes, but only with high-temperature seals (e.g., graphite). Our High-Temp Series handles steam up to 600°F (315°C).

Q: How long do butterfly valves last in throttling service?
A: With proper maintenance and design (like our triple offset valves), expect 10–15 years of reliable operation.

Why Choose COVNA for Throttling Applications?

At COVNA, we engineer butterfly valves for performance and longevity:
Triple Offset Design: Zero friction operation, perfect for frequent throttling.
Custom Coatings: Tungsten carbide or epoxy options for corrosive/abrasive media.
Global Certifications: API 609, ISO 9001, and TA-Luft compliant.

Explore Our Throttling-Optimized Butterfly Valves

Conclusion

Butterfly valves can effectively throttle flow in moderate conditions, especially with high-performance designs. For demanding applications, prioritize robust materials and advanced engineering—like COVNA industry-leading valves.

Need a Valve Solution? Contact Our Engineers for a Free System Audit.