Search results
Results From The WOW.Com Content Network
Tilting-disc inconel check valve Check valve symbol on piping and instrumentation diagrams. The arrow shows the flow direction. Vertical lift check valve. A check valve, non-return valve, reflux valve, retention valve, foot valve, or one-way valve is a valve that normally allows fluid (liquid or gas) to flow through it in only one direction. [1]
A safety valve is a valve that acts as a fail-safe. An example of safety valve is a pressure relief valve (PRV), which automatically releases a substance from a boiler, pressure vessel, or other system, when the pressure or temperature exceeds preset limits. Pilot-operated relief valves are a specialized type of pressure safety valve.
A double check valve or double check assembly (DCA) is a backflow prevention device designed to protect water supplies from contamination. [ 1] It is different from the two-way check valves (sometimes erroneously referred to as double check valves) used in air brake systems on heavy trucks which select from the highest pressure source.
A relief valve DN25 on cooling water pipe from heat exchanger Schematic diagram of a conventional spring-loaded pressure relief valve. A relief valve or pressure relief valve (PRV) is a type of safety valve used to control or limit the pressure in a system; excessive pressure might otherwise build up and create a process upset, instrument or equipment failure, explosion, or fire.
The most common final control element in the process control industries is the control valve. The control valve manipulates a flowing fluid, such as gas, steam, water, or chemical compounds, to compensate for the load disturbance and keep the regulated process variable as close as possible to the desired set point. [ 1]
Pinch valve, for slurry flow regulation and control. Piston valve, for regulating fluids that carry solids in suspension. Piston valve (steam engine) Plug valve, slim valve for on–off control but with some pressure drop. Solenoid valve, an electrically actuated valve for hydraulic or pneumatic fluid control.
Valve actuator. Electric actuator (blue cylinder) on a valve in a power plant. A black handwheel is visible on the actuator, which allows manual positioning of the valve. The blue valve body is visible in-line with the pipe. The valve actuator opens or closes the butterfly disc of the valve based on electrical signals sent to the actuator.
Isolation valve. An isolation valve is a valve in a fluid handling system that stops the flow of process media to a given location, usually for maintenance or safety purposes. [ 1] They can also be used to provide flow logic (selecting one flow path versus another), and to connect external equipment to a system. [ 2]