What Is Concentric Butterfly Valve

The concentric?butterfly valve?is the stem centered in the middle of the disc and the disc centered in the bore. There is no offset angle between the valve disc and the valve stem, and the valve body. I will introduce the concentric butterfly valve from the following aspects.

1.?Complete design for butterfly valves, usually have below standard

A.?API 609-2016

B.?EN593

C.?GB/T-12238:2008

2.?The flange connection standard of the concentric butterfly valve

A.?ASME B16.34:2017

B.?ASME B16.42:2016

C.?ASME B16.1:2015

D.?EN1092-1:2018, EN1092-2:1997

3.?The top flange connection standard

?ISO 5211

4.?The face-to-face length standard of the concentric line butterfly valve

A.?EN5752

B.?EN558

C.?API609

5.?The pressure test of the concentric butterfly valve

A.?GB/T 13927

B.?EN12266-1:2017

C.?API598:2019

Generally speaking, we can clearly describe a whole butterfly valve from the above five standards.

Selection of valve body and valve body materials for the concentric butterfly valve

According to the flange connection, the valve body is divided into

1.?Wafer butterfly valve--Bare hole connection, without thread

2.?Lug butterfly valve--With thread, usually 24" or more, choose a stronger U-shaped butterfly valve and make a threaded connection, the end of the pipe is often used LT type, and add a two-way top wire.

3.?Single flange butterfly valve

4.?Double flange butterfly valve

5.?U-section butterfly valve

6.?Grooved butterfly valves

According to sealing the butterfly valve is divided into

1.?Vulcanised rubber seated butterfly valves

2.?Soft seat butterfly valve

3. Hardback soft seal butterfly valve