An ammonia valve is a valve available for use in applications where ammonia will be present. A special valve is necessary because ammonia is corrosive and could damage an ordinary valve, causing a leak and potentially creating a hazardous situation. Manufacturers of chemical equipment and supplies typically carry devices rated for use with ammonia, and people can order them through catalogs or stores. It is important to make sure a valve's size and pressure rating are appropriate for the application.
Numerous systems carry ammonia, ranging from the anhydrous form used by some farmers to purified ammonia extracted during chemical processes. Valves are necessary to control leaks, release pressure, and allow people to move the contents of the system from one place to another. The ammonia valve uses materials known to resist corrosion, including appropriate gasket material to seal the valve tightly when the operator closes it. The top may be color-coded or otherwise tagged so people know what's behind the valve.
A relief valve can detect dangerous rises in pressure within a system and open to allow the contents to bleed off in a controlled way, preventing an explosion. The ammonia relief valve may route to a backup storage tank to avoid spills. This allows people to maintain safe operating conditions with the use of automated equipment that will kick in when a problem with the system arises. The ammonia valve may also have a fail-safe to force people to check the system before closing it again so the unsafe conditions do not recur.
Companies can use a variety of materials to make an ammonia valve. The size varies, allowing for installation on different kinds of systems, and the factory will test the valve to make sure it is sound and to determine how much pressure it can bear. The packaging will indicate the recommended uses according to the manufacturer. Manufacturers do not accept liability for situations where people use their products incorrectly.
As with all fittings, it is important to maintain an ammonia valve properly. People should take note of the installation date and any service recommendations such as replacing the liner on the valve on a set date to reduce the risks of leaks. It is important to confirm that the valve opens and shuts smoothly and is easy for any operator to access and use. People working with any kind of system where dangerous chemicals are present also need training in how the safety systems function and what to do in the event of an accidental release of material.