Valves are essential to any piping system as they control the flow rate and direction of liquids or gases. Two popular types of valves are butterfly valves and diaphragm valves. But what’s the difference between these two valves? Which option should you choose for your specific application? In this blog post, we will dive into the features, advantages, and disadvantages of butterfly and diaphragm valves to help you make a more informed decision.
Difference Between Butterfly Valve and Diaphragm Valve
Operating Principle:
Butterfly valves consist of a rotating disc, which can be rotated perpendicular or parallel to the flow; this movement regulates the flow rate. While diaphragm valves work by placing a flexible diaphragm over a weir or seat, and the diaphragm movement initiates the flow control. Butterfly valves are ideal for large liquid flow systems, while diaphragm valves are better suited for precise flow regulation requirements.
Connections:
Butterfly valves come in different styles, including lug, wafer, and flanged. Of these, wafer valves use fewer parts and are easier to install and remove. On the other hand, diaphragm valves use threaded, flanged, or union connections and are typical in high-pressure applications such as oil and gas, chemical, and pharmaceutical industries.
Durability:
Butterfly valves are durable, require minimal maintenance and are excellent for low-pressure applications. They are resistant to corrosion and erosion thanks to their fewer contact points. However, although made from materials like PTFE, EPDM, and Viton, diaphragm valves have many contact points, making them susceptible to damage, particularly in high-pressure applications.
Application:
Butterfly valves are common in pipelines because they can move the disk to any position – completely open or closed. However, they are not recommended in slurry, abrasive granular materials, and highly viscous media because the disk’s sealing is fragile. Diaphragm valves are useful for applications involving slurries or abrasive materials thanks to their self-flushing system, which keeps the valve clean. They also work well in high-purity environments, gas applications, and vacuum applications.
Cost:
Butterfly valves are relatively inexpensive compared to diaphragm valves. They have fewer parts, significantly reducing their cost compared to their counterparts. On the other hand, diaphragm valves are costly due to their complex designs and materials.
Conclusion:
In conclusion, both butterfly valves and diaphragm valves have their unique set of benefits and limitations. When deciding which valve to use, consider the application, operating efficiency, cost, and maintenance requirements. With their robust design, butterfly valves are perfect for industrial and commercial applications, while diaphragm valves are ideal for high-pressure applications requiring precise flow control. We hope this blog post has been beneficial in understanding the differences between butterfly valves and diaphragm valves.
