All About Valves
Valves are devices that control the flow of fluids and gases. Some are used to regulate the rate of flow, and others are used to stop it completely to prevent flooding or allow repairs to be made. There are dozens of different types of valves, and each performs a specific task. Faucets are familiar types of valves. But there are many other valves used in the typical residence.
A number of terms are used synonymously for valves. They may be called faucets, stops, bibbs, cocks, taps or even drains. Tradition dictates their use. Their functions are often hard to distinguish.
Ordinarily, a faucet is considered to be any valve that has an integral discharge spout. A boiler drain, a hose bibb, and a sillcock are all faucets, while a gate valve, a ball valve, or a stop are not.
For the purposes of this article, we’re including any faucet not attached to a fixture. On the other hand, we’re not considering shower valves because they’re usually selected with other bath faucets, and are discussed elsewhere on this site.
Valves must seal properly when closed. Leakage between the valve element and the valve seat is controlled by precision-machined surfaces, resulting in carefully controlled clearances. This helps to minimize contamination in water systems, which causes valves to stick, and causes abrasions of the valve seats, resulting in leakage between the valve element and valve seat.
More information can be found for specific types of valves by clicking on the links below:
