Butterfly valve types

The butterfly valves has the characteristics of simple structure, small volume, light weight, material consumption, small installation size, rapid switch, 90° reciprocating rotation, small driving torque, etc. It is used to cut off, connect and adjust the medium in the pipeline. Fluid control characteristics and shut-off sealing performance.

Main classification

Divided by drive

(1) Electric butterfly valve

(2) Pneumatic butterfly valve

(3) Hydraulic butterfly valve

(4) Manual butterfly valve

According to the structure form:

(1) Center sealing butterfly valve

(2) Single offset butterfly valve

(3) Double offset butterfly valve

(4) Triple offset butterfly valve

Sealing surface material points:

(1) Soft sealing butterfly valve.

1) The sealing pair is made of a non-metallic soft material to a non-metallic soft material.

2) The sealing pair is made of a metal hard material to a non-metallic soft material.

(2) Metal hard seal butterfly valve. The sealing pair is composed of a metal hard material and a metal hard material.

According to the seal form:

(1) Forced sealing of the butterfly valve.

1) Elastomeric sealing butterfly valve: The sealing specific pressure is generated by the valve plate pressing the valve seat, the valve seat or the valve plate when the valve is closed.

2) External torque sealing butterfly valve: The sealing specific pressure is generated by the torque applied to the valve shaft.

(2) Pressure-filled sealing butterfly valve: The sealing specific pressure is generated by the pressure of the elastic sealing element on the valve seat or the valve plate.

(3) Automatic sealing butterfly valve: The sealing specific pressure is automatically generated by the medium pressure.

According to the working pressure:

(1) Vacuum butterfly valve. A butterfly valve with a working pressure lower than the standard atmospheric pressure.

(2) Low pressure butterfly valve. Butterfly valve with nominal pressure PN<1.6MPa.

(3) Medium pressure butterfly valve. The nominal pressure PN is a butterfly valve of 2.5--6.4 MPa.

(4) High pressure butterfly valve. The nominal pressure PN is a butterfly valve of 10. 0--80.0 MPa.

(5) Ultra high pressure butterfly valve. Butterfly valve with nominal pressure PN>100MPa.

According to working temperature:

(1) High temperature. t>450 °C butterfly valve.

(2) Medium temperature butterfly valve. Butterfly valve with 120 C < t < 450 °C.

(3) Normal temperature butterfly valve. A 40C < t < 120 ° C butterfly valve.

(4) Low temperature butterfly valve. A butterfly valve of 100 < t < 40 ° C.

(5) Ultra-low temperature butterfly valve. A butterfly valve with t < 100 °C.

According to the connection method:

1, the wafer type butterfly valve

The disc of the wafer type butterfly valve is installed in the diameter direction of the pipe. The valve is fully open.

The clip-on butterfly valve is simple in structure, small in size and light in weight. The butterfly valve has two types of sealing: elastic sealing and metal sealing. Elastomeric sealing valve, the sealing ring can be mounted on the valve body or attached to the periphery of the disc.

2, flange type butterfly valve

The flanged butterfly valve is a vertical plate structure, and the valve stem is a sealing ring of the integral metal hard sealing valve.

It is a composite structure of flexible graphite plate and stainless steel plate, which is mounted on the valve body, and the sealing surface of the butterfly plate is welded with stainless steel. The seal of the soft seal valve is made of nitrile rubber and is mounted on the disc.

3, lug butterfly valve

4, welded butterfly valve