What Are Valves? How Do They Work?

The most basic function of valves is to control, adjust or guide the flow in a system or process. Each of them has a series of characteristics to match the most suitable equipment.

Functions of valves

Valves have various functions, including:

• They can start or stop flow based on valves condition

• They can adjust flow and pressure in the piping system

• They can control the flow direction in the piping system

• They can throttle the flow rate in the piping system

• They can improve safety by releasing pressure or vacuum in the piping system

Explanation of valves opening method

Although many valves can achieve similar goals, their mechanical properties are different. The way valves open and close not only affect the overall performance, but also determine the degree of flow control and the speed at which valves are operated.

Classification of valves

In addition to the mechanical movement associated with valves, the driving method also needs to be considered. In most cases, valves are divided into three categories:

Manual valves: They are usually manually adjusted. These valves are driven by manual wheels, manual level gauges, gears or chains.

Actuator valves: They are usually connected with an electric motor, an air or pneumatic system, a hydraulic system or a solenoid. These valves can be used for remote control and automation of high-precision or large-scale applications.

Automatic valves: Some valves are activated when certain flow conditions are met, such as check valves that close during the backflow process or relief valves that activate when overpressure conditions are detected.