All You Need to know about Valves

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All You Need to know about Valves
What are Water Valves and how are they made?

Water valves are designed to handle and control the flow rate of hot water, cold water, ground water, potable water, salt water and/or wastewater.

Valve Classification

There are several methods that can be used to classify valves, these including both the control mechanism and valve function.

Valve Function

Valves are a part of many daily- used machines and can perform a variety of functions. The three common valve functions include stopping and starting flow, throttling (control) flow, and acting as a non-return check for flow (check).
Stop/Start valves are used for systems that do not need the flow throttled. The valve simply opens to allow the flow and closes to stop flow.
Throttle or control valves allow the speed and capacity of flow through the system.
Control Valves.
Non-return, or check valves control the direction of flow. Flow in the desired direction opens the valve, while flow in the opposite direction forces the valve closed. These valves are important for preventing backflow to systems in applications such as wastewater management.

Check Valves

Methods of Controlling the Operation of Valves

The mechanism to control flow can vary based on the application of the valve. In general, there are two main ways of controlling flow through a valve.

Linear motion and Rotary motion, with some valves also being ‘Quarter turn valves’ where they are in their fully open or fully closed state after a 90° turn of the stem.

Different Types of Water Valves

There are many types of water valves.

Ball valves provide tight shut-offs, but are not suitable for sanitary applications.
Butterfly valves permit flow in only one direction.
Check valves are self-actuating and prevent the reversal of process flow.
Diaphragm valves separate the flow of water from the closure element.
Directional valves steer flow through selected passages.
Diverter valves redirect process flow.
Drain valves reduce surplus media.
Float valves open or close automatically as the level of a fluid changes.
Foot valves are check valves with a built-in strainer.
Globe and pinch valves are other types of linear motion devices.
Needle valves have a slender, tapered point at the end of the valve stem.
Poppet valves open and close with a sealing device and spring.
Plug or stop-cock valves are designed for both on/off and throttling functions.

Other types of water valves include sanitary, sampling, shut off, solenoid, and toggle valves.