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Check Valve Vs. Ball Valve – Understanding the Key Differences

March 18, 2024 by Brina

Check valves are essential components of any fluid system that transfers liquids, gases, vapors, and more. These valves enable one-direction flow while preventing backflow.

Ball valves employ a spherical ball inside the flow path to prevent reverse flow. As they rotate during operation, self-cleaning occurs as the ball rotates.

Table of Contents

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• What is a check valve?
• What is a ball valve?
• What is the difference between a Check Valve and Ball Valve?

What is a check valve?

A check valve allows liquids, gases, or steam to flow only in one direction – not backward. They’re commonly found in industrial and utility applications like wastewater lines, water treatment plants, and gas export facilities.

The valve can be designed as a ball, disc, piston, or poppet. It comes in single-door or double-door models with an inlet and outlet port for convenience.

Check valves differ from other kinds of valves in that they operate based on differential pressure rather than just a trickle of flow. This means a specific minimum inlet pressure is necessary to open the valve (known as the cracking pressure). When this pressure drops below this minimum or backflow attempts to take place (backflow), then the valve will close automatically.

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What is a ball valve?

A ball valve is an electrical device that controls the flow of liquids and gases through pipes by turning a ball with a hole through it. When turned 90 degrees, this hole lines up with the flow direction, allowing media to pass through it freely; if turned in the opposite direction, however, media cannot pass through the valve.

Ball valves come in three basic designs: one-piece, two-piece, and three-piece. Each design has been optimized for specific purposes.

Ball valves can be controlled manually or automatically by using either electrical or pneumatic actuators. They also have the capacity to turn off automatically in case of a power outage or for failsafe purposes.

What is the difference between a Check Valve and Ball Valve?

Both check valves and ball valves are on-off flow control valves that allow gas, liquid, and solids to pass through their system. Both types of valves are airtight and capable of withstanding a variety of temperatures and pressures.

Check valves are usually specified for cracking pressure or the minimum upstream pressure at which they will operate. This is an essential concept in check valve design as it guarantees that the valve will perform at its optimum capabilities.

The obturator of a check valve is either a ball that lifts under cracking pressure or an aluminum flapper which opens and closes by gravity. These can be made from various materials, such as steel, copper, aluminum, or polymer, depending on the application.

Ball valves are commonly used in a variety of applications, such as firefighting equipment and sewage systems, due to their cost-effective design and large flow capacity.

However, this design is more vulnerable to water hammer and requires more room for the flapper to swing open and close. They’re less versatile than ball check valves as they cannot support downward vertical flow, and customization can be tricky, which is why they are often combined with other valves, such as plug valves or butterfly valves, to meet specific application needs.

Xintai Valve is one of the world’s leading manufacturers of industrial valve products. Their product portfolio comprises six categories and thousands of varieties, such as control valves, cryogenic valves, globe valves, ball valves, check valves, butterfly valve power station valves, oxygen valves, hydraulic control valves, and thread valve antibiotic valves.