Butterfly valves have been used going all the way back to the late 18th century. In a Flow Control article, The evolution of the butterfly valve, Emerson’s Joanne Lunsford describes some of the advances to for this important technology in manufacturing and production processes.
One key advantage of butterfly valve technology is that they:
…offer an effective shutoff method for the isolation and regulation of fluid flow. A successor to traditional gate valve technologies — which were heavy, difficult to install and did not provide the tight shutoff required to prevent emissions and production inefficiencies — butterfly valves were developed in 1950 as a smaller, lighter alternative that would effectively address leakage issues.
Originally designed for low-pressure, low temperature applications advancements enabled a wider range of use.
With the emergence of developments in elastomer-lined resilient seated butterfly valves, end users were able to use them in applications with higher temperatures and more corrosive services, such as light corrosive service, food service and hot air.
An example of this type of valve for use in food & beverage industry applications is the Keystone Figure 990/920.
Also, butterfly valves’:
…more compact, lighter weight design could be used to help combat emissions and safety challenges in a wider range of applications.
A further innovation for even greater temperature and pressure limits is:
…a double-offset disc that reduced rubbing and wear on the seat, which extended the life of the valve. It could also withstand applications up to 1000°F (537°C) and pressures up to 1480 psi.
For applications requiring a tighter shutoff than was possible with gate valves and high-performance butterfly valve, the triple-offset butterfly valve was developed. These achieve:
…bidirectional zero leakage according to international standards, triple-offset valves (TOVs) provide tight shutoff through a combination of metal-to-metal torque seating and quarter-turn nonrubbing rotation. This type of valve solution is capable of handling the extremes of temperature and pressure while providing zero leakage metal sealing.
Read the article for more on some of the newer challenges and specific application fits for various industries. Visit the butterfly valve and triple-offset valve sections on Emerson.com for more on the valve technologies to best fit your application. You can also connect and interact with other valve experts in the Valves, Actuators & Regulators group in the Emerson Exchange 365 community.