Monday, August 2, 2010

Types of Valves

lvelvvBasically there are 4 types of mechanical valves:

1. Flow Regulating Valve - The purpose is to control the amount of flow in the pipe. Eg Butterfly or Globe Valve

Butterfly Valve
 
Globe Valve
 


2. Stop Valve - To completely stop or start the flow of fluid. These valves are good for "On" and "Off" application but poor in controlling the amount of flow. Eg Ball Valve or Gate Valve

3. Check Valve - Allows the fluid to flow in only one direction and prevents backflow of fluid

4. Pressure Regulating Valve - If the pressure in the piping system exceeds a certain amount, then the valve opens to relieve the pressure in the sytem. Eg Steam bypass valve

Generally the valves are color coded as per the fluid they are carrying
White Color - Steam
Blue Color - Water
Yellow - Fuel/oil
Dark brown- Sewage