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Shut-off valves: Gate, globe & ball valves – which should you use?

Shut-off valves are incredibly handy little components because they enable you to complete work in one area – for example, a kitchen – or even on a particular appliance, like a dishwasher, without cutting off the water supply to the rest of the house or building.

These days, the mostly commonly used variety are ball valves, but some houses and buildings also use gate and globe shut-off valves. Which should you use for your next application? Learn more about each type to help make a decision.

Difference between gate, globe and ball shut-off valves

Gate valves

Gate valves have sliding parts that control the flow of water. They’re operated by a wheel that moves up and down, and when the gate is at the lowest possible position, the flow of liquid is blocked. At the highest position, liquid can flow freely. These types of valves either have rising stems so you can easily see if they’re open or closed (ideal for pump operators for example), or non-rising stems which make it more difficult to tell.

Gate valves often corrode, which causes difficulty in their opening and closing mechanism, and can lead to breakages that require repairing (which is difficult) and/or replacement.

Gate valves are preferable for applications where they will be fully open or closed, as partially open gate valves will vibrate and this can cause damage. They’re ideal for slurries and viscous liquids, but shouldn’t be used in sanitary applications.

Globe valves

These kinds of valves are designed to limit the flow of water and are operated, like gate valves, with a wheel and stem. The difference however is that the stem is attached to a stopper that seals a baffle shut. This forces the water into a Z-shaped flow.

Globe valves reduce water pressure by using the stem to close against the flow. This makes them ideal for regulating the flow of liquid.

It’s often prohibited to use globe valves for the main shutoff and for water heaters: for these applications, full open valves, like gate or ball valves, must be used.

Ball valves

Ball valves are one of the most popular kinds of valves because they’re highly durable and able to work perfectly even after years of inactivity. The inside of a ball valve contains a brass or steel sphere with a lever attached. When the lever is moved parallel to the pipe, the opening of the sphere becomes aligned with the flow of water. When the lever is moved perpendicular to the pipe, the flow of water is blocked.

The range of movement of this lever is only a quarter-turn, the advantage of which is quick shut-off. Having a lever instead of a wheel also offers a number of benefits, including the fact that it’s easier to manoeuvre than a wheel, and operators can instantly tell if the valve is open.

Ball valves are not recommended in tight locations. They’re ideal for slurries and handling large flows of gases and/or liquids, but not recommended for throttling applications.

Durable, high-quality ball valves from the best in the business

Plastinternational specialises in ball valves – more specifically, our own SABS-approved EzeeFlow plastic ball valves. Lightweight, affordable and incredibly resilient, they’re ideal for a range of indoor and outdoor applications.

Learn more about our EzeeFlow plastic ball valves now or get in touch with us for advice on choosing the right

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