What Are The Types Of Valves In Water Distribution Systems?

A valve can be defined as a style of fitting that regulates, controls, and directs the flow of fluids via a pipe. Valves are often employed in water distribution systems to guide the flow, shut off water access, prevent backflow, and alter water pressure.

What Is A Water Supply Valve?

Water supply valves control the flow and temperature of water through pipelines and plumbing fittings. These valves also maintain a steady flow and volume when correctly placed and operated properly. They are frequently employed in a wide variety of economic and industrial applications.

Wastewater treatment plants, pharmaceutical factories, chemical plants, and car production all depend upon water supply valves for fluid control and direction. Though valves are a kind of fitting, they’re often addressed as a separate, distinct category as each valve acts independently.

Plastic, lead-free brass, cast iron, stainless steel, and galvanized tubing are among the materials used to make valves. There are different kinds of valves used in the water distribution systems and each serves its own function.

Why Valve Plays An Important Role In The Water Supply And Distribution System?

Valves are essential components of the water distribution system. The distribution system includes a lot of components including storage tanks, pipes, valves, and hydrants.

1. Ball valves

Ball valves are the vastly used shut-off valves. They control water flow in pipelines through a rotational ball placed in the middle of the valve. This ball contains a hole through its centre that regulates the flow of water. When the ball’s hole is parallel to the water inlet, water can surge through the valve and escape into the pipes. When the hole is rotated 90° to the pipe through a handle, the passage is blocked, and water cannot flow through the valve. Rotating the handle by 1/4 turn is sufficient to seal off the flow of water.

Ball valves are common due to their reliability, speed, and durability. These valves are greatly used in residential and industrial applications to start and stop the water flow without a pressure drop. The ball produces a strong, watertight seal within the valve that prohibits leaking. Ball valves are also excellent for emergency applications where water flow needs to be blocked rapidly. However, these valves can only open and close water passages; they can not throttle the flow, as it risks destroying the seats or the ball.

The various designs of ball valves enable them to alter or deflect the water flow through multiple ports. The multi-port ball valves can divert water through as many as four different tracks. While most shut-off valves are only organized to control valves in a single direction.

2. Gate Valves

Gate Valves are widely employed in water distribution systems. A wedge-shaped metal gate is placed, which might be lowered to prevent water flow and lifted to revive flow. When the gate is fully lifted, it entirely retracts, enabling water to flow through with no pressure decrease. On top of the valve, a wheel-shaped lever operates the gate valves.

One can regulate the movement of the gate within the valve by turning the lever. These valves provide progressive flow limitation, preventing blast. Sometimes a loud noise is caused by an abrupt change in direction or halts, leading to a hammering sound within the pipe.

Gate valves, like ball valves, simply start or stop the flow of water because utilizing them for throttling will reduce their efficiency. Gate valves are ideal for straight-line flow with little constraints and diversions, like in large facility lines.

In general, gate valves are seen in older plumbing systems since ball valves are more reliable nowadays. Furthermore, they will last longer if used just occasionally. A valve is good for water systems where the flow of water must be switched on and off more often.

3. Globe valve

Globe valve are typically used to regulate water flow in pipelines. Unlike ball valves and gate valves, globe valves are suitably designed to start, stop, and throttle the flow of water. The spherical body of the globe valve homes a stationary ring seat. When the knob outside the valve is twisted, a disc-shaped device opens up a Z-shaped path and allows water to flow from one section into another. The knob can be opened and closed either completely to open and close the flow or partially to throttle the flow.

Globe valves provide a larger pressure drop than other shut-off valves. The curved Z-shaped passage inside the valve is more flow restrictive than ball valves and gate valves. So, they are ideal when managing water flow at lower pressures. But, since globe valves open and close gradually, they avoid water hammer.

4. Butterfly Valves

This valve is another form of shut-off valve that helps to control water flow. A valve contains a revolving disc within the center. Like ball valves, this moving disc is controlled by a quarter-turn of a handle. This disc bursts open because the handle is twisted, enabling water to enter through the valve. When the disc is closed, it prevents water from moving.

Butterfly valves are a part of the rotary motion valve family. This is often because of the fact that they manage water discharge by running a mechanism that causes the flow to shut. Although less functional than globe valves, a butterfly valve is also progressively opened to throttle water.

Some valve designs lock the disc half receptive and keep the throttled position. However, it’s not recommended to utilize a valve to throttle flow for extended periods of your time. Continuous exposure to flowing water will corrode the disc and compromise the watertight seal.