Learn more about butterfly valves and how to maintain them

 

What is a butterfly Valve?

D Chel Valves is the leading butterfly valve manufacturers in India. The butterfly valve manufacturers were initially utilised in situations when a tight closing was not strictly required. But over time, these valves have been produced with somewhat tight seals made of rubber or elastomeric materials that offer good shut off similar to other types of valves. When there is not much room, butterfly valves are used. In contrast to gate valves, butterfly valves can be utilised in both the completely open and fully closed positions as well as for throttling or regulating flow.

Compared to a gate valve, a butterfly valve manufacturers has a lower pressure loss. This type of valve has an L/D ratio that is around one-third that of a gate valve. Both large and small sizes of butterfly valves are utilised. They can be controlled by a hand wheel, a wrench, or a gearing system. 

Because they require less material and less construction effort, butterfly valves are typically less expensive than gate valves. As the disc pivots about an axis on or near the pipe axis, they are also simpler to operate against imbalanced water pressures. Consequently, water distribution systems today frequently include butterfly valves. Butterfly valves can have a resilient seat or a seat that is composed of metal. In the latter case, the seat is typically fastened to the body of smaller valves or to the disc and is typically made of natural or synthetic rubber. Dchel valves also manufacturers different types of Butterfly Valve which we’ll study in this blog.

Classification

 

Industrial Valves can be categorised in a variety of ways, including by control method and function. Quarter-turn valves are butterfly valves. They control flow as well as opening and closing systems.

Types of Butterfly Valves: 

1.Flexible Butterfly Valve: Where there is a lack of space, butterfly valves are used. butterfly valves manufacturers, in contrast to gate valves can be utilised in both the completely open and fully closed positions as well as for throttling or regulating flow. Compared to a gate valve, a butterfly valve has a lower pressure loss.

2. Hydraulic Counterweight Butterfly Valves: The hydraulic Counterweight Butterfly Valves is intended for installation at the pump's output in water-filled pipes and functions as both a globe valve and a check valve. Water hammer can be reduced or eliminated, and working medium flow can be stopped from reversing, by controlling the closing time and speed. And Can replace the functions of Gate Valve or Check Valve.

3. Double Eccentric Butterfly Valves: Double eccentric butterfly valves manufacturer are frequently utilised as an alternative to gate valves in below-ground water delivery systems. In general, butterfly valves are less expensive than gate valves to install underground and require a less bury depth, especially when they are substantial in size.

4. Flanged Butterfly Valve:  Metal is the most typical material used to make flanged butterfly valves, however other materials such as cast iron, plastic, and stainless steel may also be used. Because they are used for a variety of purposes, flanged valves come in a variety of diameters, from a few inches to a few feet.

5.Wafer (Lug) Butterfly Valve: This makes it possible to install them into a system with just two sets of bolts and no nuts. A different set of bolts is used for each flange to install the valve between them. It is a type of butterfly valve manufacturers in India whose configuration enables either side of the piping system to be detached without affecting the other side. 

Function 

Butterfly valves manufacturers can be used for throttling or on/off service. A valve controls the pace and capacity of media through the valve when it throttles or adjusts the flow.

• A butterfly valve for on/off services is typically line size and requires the lowest pressure drop possible in the open state.

• An essential component of a fluid handling system is a control valve. For this purpose, choosing a butterfly valve necessitates additional calculations that take system needs into account. The user must be able to determine both the maximum flow needed, which is equal to the design flow, and the maximum pressure drop permitted, which is typically no more than three to five pounds and is given by the consulting engineer. Never let the pressure decrease go below half of the inlet pressure.

Butterfly Valve Maintenance

• Cycle the valve once a month or more if it is not used regularly.

• Relieve the system pressure before maintaining the valve.

• To remove from pipework reverse the installation sequence.

• Replace valve seat (liner) by removing the stem and disc. Press out the liner and replace it with a new part. Reinstall the disc and stem along with seals and clips. Refit into line as in installation sequence.

• If the valve is operating in a dry application (eg compressed air) ensure to lubricate the disc and seat regularly to prolong life span

• For operational instructions please see each video link under products.

Field Testing

• Rubber seated butterfly valves are designed to hold rated pressures only. Test pressures above rated working pressure in the closed position can cause damage to the valve.

• With the disc in the open position the pipeline can be tested up to the valve hydrostatic test pressure.

• Seat leakage can occur with foreign material between the seat and disc. If this occurs, open the valve 10 to 15 degrees to obtain high velocity flushing action. Close and repeat if necessary.

• Seat leakage can result from a rotational shift in position of the disc in relation to the body. Readjust the closing stop on the actuator/gearbox as necessary.

• For dry applications actuator stops can be adjusted to stop the disc burying all the way into the seat. This will still allow a bubble tight seal but prolong the lifespan of the seat.

Operation

• Do not use the valve at pressures above its working pressure.

• If the valve is jammed in a position between open and closed check the actuator operation. If necessary remove the actuator and manually operate the valve to find fault. Remove and check valves for foreign objects if required (see maintenance).

• Excessive torque from the actuator can damage the internal valve parts.

Conclusion

Butterfly valve is the most common type of pressure control device in use today. It is used in a wide variety of applications, such as boiler systems, air conditioning and refrigeration, chemical plants and many others.

D Chel Valve is India’s leading butterfly valve manufacturers and ball valve manufacturers. To know more about valves visit our website dchel valve for more details and specifications.