What are valves?
At their basics, valves are the devices that work to regulate, control and direct the flow within a process or system. They usually feature the characteristics range and it helps in defining applications. If you are looking for controlling the flow providing safety in systems that are solid, liquid, gas or anything in between. There are many stainless steel valves available to help the flow control.
Following types of valves are used while depending on the requirements. The valve cost can be up to 20 to 30% of the overall piping cost. The cost of a given size and type of valve can vary up to 100%. For example if anyone chooses a ball valve over butterfly valve for similar functions. It will cost users more. The selection valve is very important to the economy and operations of the process plants.
Following are the types of valve that can be used according to the requirements:
· Gate valve
· Globe valve
· Check valve
· Plug valve
· Ball valve
· Butterfly valve
· Needle valve
· Pinch valve
· Pressure relief valve
· Pressure regulating valve
· Diaphragm valve
· Angle valve
· Pinch valve
· Flush button valve
· Solenoid valve
· Piston valve
· Y-type valve
· Control valve
Common valve types
There are 3 types of valves that are common:
1. Manual valves
These manual valves are adjusted by hands. These use hand levels, hand wheels, gear wheels and chains to actuate.
2. Actuated valves
These actuated valves are usually connected to electric motors, pneumatic or air systems, hydraulic systems or solenoids. These valves allow the remote controls and automation for high precision and large scale applications.
3. Automatic valves
Some of the valves are activated when the flow is specific and the conditions are met. Check valves closes during the pressure of backflow release. Valves are activated when an open pressure condition is detected.
Valves providing many functions
Valve provide many functions and that includes:
1. Stopping and starting flow that is based on the valve state
2. Regulating pressure and flow with in the piping system
3. Controlling and looking after the flow direction with in the piping system
4. Throttling the rates of flow with in the piping system
5. Helps in improving the safety through relieving vacuum and pressure in the piping system.
Selection criteria of type of valves
In selection criteria the most important thing to consider is that the valve is used for throttling. Water hammer is the surge pressure that takes place when a moving fluid changes direction or stops. Another thing to keep in mind while selecting a valve is the nature of the fluid through the valve. Valve actually depends on the valve type. One of the important things to keep in mind when replacing a valve is to do face to face distance between flanges. Generally a valve needs to fit themselves in spaces fixed between pipes.
Choosing the right valve is the most important act and it is complex. Start it with the general characteristics such as valve size, valve design and actuation method. You can then quickly know and can limit your options to choose the best valve type for your needs.