Butterfly Valve

What is the difference between gate valve and butterfly valve?

 A gate valve has a paddle which is used to allow flow in the open position, or raised position, and stop the flow in the closed or lowered position, gate valves raise and lower in the vertical plane. 

Butterfly valves have a disc, which is rotated a quarter turn either clockwise or counter clockwise, to allow flow media. 

Can butterfly valve be used for flow control?

 Butterfly Valves are generally used for handling large flows of gases or liquids, including slurries, but should not be used for throttling for extended periods of time, as this can cause damage to the seat and disc. 

What is a high-performance butterfly valve?

In a high performance butterfly valve, the disc is eccentric, or offset, from the valve seat. As the disc starts to rotate, it moves away from the seat instead of across it. This type of valve uses the line pressure to help it seal. This feature allows the use of offset butterfly valves in high‐pressure applications such as ethanol or HVAC. It generally uses PTFE or plastic as its seat material, but metal seats are also available to meet fire‐testing specifications 

What is triple offset butterfly valve?

Triple offset butterfly valves ensure the safe function and tightness even in case of changing temperatures or in case of pressure peak. It also eliminates friction in the seat area when opening and closing the valve, minimising wear of the sealing elements, and significantly prolonging the service life of the valve.  

The first offset shifts the axis of the shaft rotation off the plane that lies on the pipeline axis.  The second offset moves the centre plane of the closing element parallel to its flat surface outside of the axis of its rotation.  

The third offset deflects the axis of rotational symmetry off the seat surface outside of the axis perpendicular to the flat surface of the disc, running through its centre. A set of all these offsets results in specific valve properties such as friction elimination during opening/closing cycle, ideal contact of disc and seat in closed position and its sophisticated geometry naturally prevents the disc from moving beyond the safe limit and directly defines the correct alignment of sealing elements. 

What is a double eccentric butterfly valve? 

  A double eccentric butterfly valve is designed with tilted and fixated disc for extended service life and easy operation. 

What is a resilient seated butterfly valve?

Resilient seated butterfly valves are a valve that has successfully passed the certification process of the German Institute DVGW CERT GmbH for potable water applications. Valves with this certification are available in sizes DN32-DN800 and are suited for conditions with working temperatures from 0 ° to 40 ° C and pressure ratings up to 16 bar.