Butterfly valves,have compact structure,simple design,good performance,and easy maintenance.
They are one of the most popular industrial valves.
We normally have resilient seated butterfly valves,or rubber lined butterfly valves.in this catagory,we have wafer rubber lined butterfly valves,lug rubber lined butterfly valves,U type rubber lined butterfly valves and double flange rubber lined butterfly valves.
Because the resilient seated butterfly valve has rubber lined body and seat,the tightness is excellent and always zero leakage.
but it’s not suitable for high temperature and easy to wear,which results in shorter life,compared to the Metal seated butterfly valves.
And it’s not suitable for high pressure medium.
The metal seated butterfly valve,is usually designed with triple offset.it’s including the wafer triple offset,lug triple offset,flanged triple offset and buttweld triple offset.
Both sealing surfaces of valve are metal material or other hard material, which has not so good sealing performance, but has good mechanical properties, such as being high temperature resistant and anti-wear.
Generally speaking, there are the following differences for butterfly valves of two different seats.
<1> Different Structure
Central line design for resilient seated butterfly valve while double or triple eccentric design for metal seated butterfly valve.
<2> Different suitable temperature
we use resilient seated butterfly valve in normal temperature,while Metal seated butterfly valve is used in low,normal and high temperature.
<3> Different pressure
Resilient seated butterfly valve are suitable for low and normal pressure and Metal seated butterfly valve can also suit the medium of middle-high pressure.
<4> Different sealing performance
Resilient seated butterfly valve and Metal seated butterfly valve have comparative good sealing performance. The later can seal well in high pressure and temperature.