What is a butterfly valve & working scenario?
A butterfly valve is a kind of disc valve which regulates the flow. It is a valve in which the obturator rotates about an axis at right angles to the flowing direction, flow surpasses around the obturator in the open position. This butterfly valve contains a round disc or plate built with a stem through the middle or enclosed offset. While opening, the disc starts to pivot 90 degree in the valve bore, by an aligned flow, creates a free flow path. It is identical to ball valves in its 90 degree rotation and allows a quick close. Butterfly valves thin profile in between flanges makes them lighter in weight and creates a small install foot print. That’s why it has been popular for so many years in the Engineering field. This elegant design reduces the cost of butterfly valves when compare to other valves. There are many numbers of butterfly valve manufacturers available across India. They produce various types of butterfly valves, each has been designed with unique features, applications. Every type is decided only by the stem orientation to the disc and the seating angle of the valve where the disc closes.
The different kinds of butterfly valve are:
Concentric -Wafer Type
Concentric - Lugged Type
Concentric-Double Flanged Type
2x Series
3x Series
Concentric -Wafer Type
Concentric wafer type is prevalently used in water treatment and other industries. The main traits behind its usage is its small size, easy installation, light weight with budget cost along with a compatible design. Its disc is very simple, the centre line sealing is also quite elegant and the disc able to touch the rubber seat exactly.
The concentric wafer type sizes are available from 1” to 100”. Concentric type in nature with moulded or renewable seated along with Lug, wafer and double flanged ends.
Concentric - Lugged Type
This is a lug type valve containing threaded holes and useful in many applications. As a stopper, the valve is being used and as a tap to discharge at the pipeline end open/close and flow control. Installation and uninstallation from the pipeline is made easy by the threaded holes. Hydraulic / Electrical/ Manual and Pnematic are the kinds of operation.
Concentric-Double Flanged Type
This type has a Concentric design, contains one-piece body type with flanges at the ends which yield additional resistance. The vulcanized elastomer allows to use it at the pipe end without using counter flange. The interchangeability is allowed by the face to face distance with other kinds of valve. It is built with bi-directional sealing, 0% leakage. This Concentric-Double Flanged Type is used in power generation, air conditioning, food, paper mills, Mining and heating.
2x Series
In the Butterfly valves 2X series the disc movement is designed as a double offset. Such movement reduces the concentrated wear points on the sealing ring and expands its life time. The body pattern is flanged.
The valve has extended for preventing heat conduction in the sealing area during the welding installation. Inspection, maintenance and replacement are easily done with the help of an inspection door on the top of the body. So, there is no need to cut the pipe or remove the valve.
3x Series
Triple offset is the disc movement in Butterly 3X series. During the cooling period, the internal stress in the bonnet is prevented by bolting all bonnet joints. The extended bonnet ensures that the gland area remains free from freezing even at the down temperature.
