Using Butterfly Valves for Control Applications

Did you know? Butterfly valves are the best control valves. Many people wonder when is it the right time to use a butterfly valves for a control application. The answer to this question is that a butterfly valve can always be used for control. All butterfly valve manufacturers will tell you that it is important to carefully size and select any valve that you wish to use for control applications.

This is to ensure that the process can be controlled accurately, minimising variability and all the inherent instability problems that this can bring. It can also minimise the impact on raw material and utility costs. However, valve selection is often based on reasons other than controllability.

When you select a valve for a given control application, there are two major considerations. One is the total range of conditions that the valve will be expected to control against, the second is the installed gain of the control valve across its operating range.

The gain is the ratio of rate of change of input to rate of change of output, so if the input signal is increased by 10 percent, causing the flow rate to change by 10 percent, then the gain is deemed to be one.

Butterfly valves for control applications are often regarded as a great and economical choice. It is a great alternative to globe and other control valves in applications where 1 to 2% accuracy is acceptable. The process conditions will determine whether a resilient seated or high performance butterfly valve should be selected.

OEM metal seated valves are the most economical choice. If pressures and temperatures are not extreme, this type of valve should work just fine. If temperature and pressure exceed the limits of a resilient seat, a high performance butterfly valve purchased from wafer butterfly valve suppliers is necessary.

Valves for various applications are usually selected based on their costs. Butterfly valves are selected due to their low installation costs. When choosing valves for control, the linear flowing characteristics should also been looked at. Since a butterfly valve does not have linear flowing characteristics, it becomes difficult to control. To gain control, it is a good idea to add a positioner to the valve. Also, make sure that the operating process conditions are ideal for proper control. Excessive temperatures and high velocities always need to be considered.

Few reasons people use butterfly valves are because they offer superior chemical resistance, they use less metal in their manufacturing process, they weigh less and they are compact which reduces the need for bracing or supports.

If you are looking to get effective control, choose butterfly valves.

Mr. MohanRaj, Managing Director of Sakthi Auto Anciliary Pvt Ltd, Coimbatore. An ISO 9001:2008 Certified Company. Manufacturer, Supplier & Exporter of Industrial Valves such as Butterfly Wafer Valves, Butterfly Lug Valves & Swing Check Valves.