Many isolation valves are available for a municipal water system. Selecting the right one impacts the efficiency, reliability, and maintenance of the water supply network. An isolation valve is typically either in the fully open or fully closed position. Gate valves are most commonly used, while check valves are also a good consideration.
Occasionally, an eccentric plug valve is selected, but they are primarily used for raw or wastewater applications, as the shape allows them to always close or open even if there is small matter passing through the pipeline. Ball valves are an inexpensive consideration for small pipes, but they typically do not last as long. A water system manager or operator has many things to consider when selecting an isolation valve for their system. Here are some questions that can help determine the right isolation valve for the right situation.
The fluid passing through the valve is one of the most important considerations. One must ask: is it raw water that may have debris or treated water that may have chemicals? Does the water system treat with free chlorine, ozone, or chloramines for disinfection? Buna-N and EPDM elastomers are the most widely used in the industry, and some believe that EPDM holds up better with chloramine use. Temperature and pressure are also important to consider, as the valve must be able to withstand the system’s operating conditions.