Want to Know About Valves

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Want to Know About Valves
What are Water Valves and how are they made?

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

Valve Classification

There are many ways that are used in the classification of valves, these including both the control mechanism and what the valve is for.

Valve Function

Valves are an integral part of many of the machines we use in daily life 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 in machines that do not need the flow controlled in a variable way. The valve simply opens to allow the flow and closes to stop flow.
Throttle or control valves allow the speed and throughput of flow through the system.
Control Valves.
Non-return, also known as check valves control the direction of flow. Flow in the desired direction opens the valve, while flow the opposite way forces the valve shut. These valves are vital 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 varies according to 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 cannot be used for sanitary applications.
Butterfly valves allow flow in only one direction.
Check valves are self-actuating and stop the reversal of process flow.
Diaphragm valves separate the flow of water from the closure element.
Directional valves direct flow through selected passages.
Diverter valves cause the flow to take a different path.
Drain valves minimise surplus media.
Float valves open or close automatically as the level of the fluid alters.
Foot valves are check valves with an incorporated strainer.
Globe and pinch valves are different 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 flow control functions.

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