The Butterfly Valve is a quarter rotation rotation valve, which is used to stop, regulate, and start flow. The butterfly valve has discs mounted on a rotating shaft. When the butterfly valve is fully closed, the disk completely blocks the line. When the butterfly valve is fully open, the disc is at the right angle with the flow of gas or liquid.
Butterfly Valve is one type of valve that is versatile, because it can be applied to piping systems anywhere, in industry, shipbuilding, platforms, housing and others. In addition, the Butterfly Valve can be installed on various media installations through it, for example by liquids, gases, mud with various levels of pressure and temperature.

Butterfly Valve Components:
Butterfly Valve only consists of four main components: body, disc, stem, and chair.
Butterfly Valve Body: Butterfly valves generally have a body that fits between two pipe flanges, the most common being the design of a lug and wafer body.

Disk Butterfly Valve: Disk is how the valve stops flowing - equivalent to the plug on the stopper, the gate on the gate valve or the ball in the ball valve. There are variations in disk design and orientation to improve the flow, sealing and / or operating torque.

Butterfly Valve Rod: The butterfly valve stem can be a one-piece shaft or two-piece (split-stem) design. Rods in most tough seating designs are protected from media, allowing efficient material selection with respect to cost and mechanical properties.

Valve seat
Butterfly: Butterfly Valve Chair resilient chair uses interference that fits between the edge of the disk and the seat to provide a cover. Chair material can be made from many different elastomers or polymers. Chairs can be fastened to the body or pressed or locked.

Butterfly valves are relatively inexpensive to build.

Butterfly valves require less material due to their design. The most economical is the wafer type that fits between two pipelines. Another type, the lug wafer design, is held in place between two pipes by bolts that join the two flanges and pass through holes in the valve's outer casing. Furthermore, the Common Butterfly Valves materials are often less expensive.

To open and close fully, this type of valve only requires a 90deg rotation or a quarter turn of the lever, so that this type of valve can be operated quickly. But this valve is not capable of setting for a certain flow size. This valve is commonly referred to as the Quarter Turn Valve.

With the channel cover material a precision disc valve is driven by an actuator shaft that is connected to the handle on the outside of the valve. From the actuator that moves or rotates the disc can be applied with a manual, hydraulic or electric motor lever. Of course with the addition of several auxiliary equipment such as valve controls for hydraulics and gearboxes that reduce motor rotation for the type of electric motor actuator. As shown in the picture below.

In the open or closed disk position at 0deg, an aerodynamic flow arises from the disk. Even though the loss of the head is slightly higher than the type of Ball Valve and Gate Valve, which in fact Ball Valve and Gate Valve actually works freely when the valve is fully open, but the loss is lower than the type of Globe Valve.  Various types of Butterfly valves can be used for various flow media, liquids and gases as well as rather dense materials such as mud, bulbs etc. The pressure and temperature of the material through this valve clearly affects the material of the manufacture, making it an important consideration in the design.

TYPE - TYPE AND TYPE OF BUTTERFLY VALVE

  • Lug Butterfly Valve
  • PVC or Plastic Butterfly Valve
  • Butterfly Valve Wafers
  • Butterfly Valve Flange
  • Butterfly Valve Butt-Welding End
      
 
   

 

Explanation:
Concentric Butterfly Valve, has a strong seat with metal disks. Doubly-eccentric Butterfly Valve, from a variety of materials used for seats and disks. Trply-eccentric Butterfly Valve, made of hard metal / steel. Eccentric types are often used in applications that require bi-directional for example oil and gas cover, LNG / NPG, in chemical factories and shipbuilding.

Wafer-style Butterfly Valve, Designed to maintain seals against bi-directional pressure differences to prevent backflow in any system that is intentionally designed for unidirectional flow.
Lug-style Butterfly Valve, with threads on both sides of the valve that allows it to be installed in a system with threaded joints or does not require a bolt nut on the flange.

Butt Welded Butterfly Valves are triple offset structures and suitable for high temperatures, high pressure, corrosion etc. Its are quarter-turn valves which are used for isolating or regulating flow. The conditions are preferred for water and gas, which makes them useful across industrial, mining and power applications.

Butterfly Valve Applications
Butterfly valves can be used across a wide range of applications. They perform well in large volumes of water applications and slurry applications. The following are some typical applications of Butterfly Valves:

  • Cooling water, water, gases, fire protection etc.
  • Slurry and similar services
  • Vacuum service
  • High-pressure and high-temperature water and steam services
  • Compressed Air or Gas Applications