Jun. 24, 2024
Disai are exported all over the world and different industries with quality first. Our belief is to provide our customers with more and better high value-added products. Let's create a better future together.
A check valve is common in control applications to ensure that the flow of liquid or gas is in only one direction. To achieve this function, check valves usually have two ports; one for fluid to enter, while the other is for the exit of fluid. In this article, we review the key functions of a check valve in industry, its application in various types of systems, and functionality vs a non-return valve.
The major functions of a check valve in flow systems include prevention of backflow, avoiding water hammer, fugitive emissions control, and pressure balance and relief.
The primary function of a check valve performs in a system is to prevent backflow. The onset of backflow could be detrimental to industrial systems in several ways. For example, backflow causes the impellers of pumps and compressors to reverse, which may cause burnout.
In an industrial setting, this equipment is quite expensive, so a check valve serves as a protective device. Also, backflow could result in the undesirable mixing of media or the contamination of upstream media. For instance, in a water treatment plant, check valves ensure that treated water does not return to the untreated water reservoir.
Another important use of a check valve is to avoid the occurrence of a water hammer. Water hammer happens when there is a rapid change in the velocity of a fluid. Generally, this occurs if moving fluid suddenly meets an obstacle, such as a valve closing rapidly. As a result, the fluid pulsates throughout the system with a significant pressure increase that may lead to pipe or equipment damage.
The damage may occur instantaneously or over time due to fatigue if the occurrence of water hammer is frequent. The design of non-slam check valves alongside an end damper is effective in preventing this phenomenon, especially in vertical tubing.
As environmental laws become more restrictive, it is important to have valves qualified according to industry standards against leakage of gasses. A dual-plate check valve functions to prevent fugitive emissions, especially when the pressure boundary is without threaded plugs. Also, this dual plate design is effective against water hammer, easier to maintain, and has a longer life span.
In certain compressor systems, there could be a need to keep some parts pressurized while others are depressurized. Achieving this is possible by strategically locating check valves to ensure air that enters pressurized sections cannot leave.
A check valve also functions effectively as a pressure relief valve to prevent excessive pressure levels in a pipe section or vessel. The check valve in such an application would vent the gas in the section into the environment or another vessel when the pressure reaches a threshold. Then, when the pressure falls below the threshold, the valve shuts the exit.
Because of the unique non-return feature of a check valve, it is common in several industrial applications as the following sections highlight.
In hydraulic systems, a check valve performs critical functions, including:
A check valve performs several functions in water pumps and water distribution systems in general. To ensure that there is always water in the pump for safe starting, check valves are always located at the pump entrance and exit lines. The presence of check valves at a pump isolates it from backflow and the harmful effects of water hammer. In water treatment facilities, it is common to find check valves in a series, so that wastewater cannot reenter the system. Also, check valves prevent elements from the environment from contaminating clean water.
pump valve on oil (petroleum) fieldBall check valves are one of the most important components when controlling water flow from the feed pump to the boiler. As boiler pressure increases beyond the pump pressure, these valves prevent backflow from the boiler to the pump. Also, they prevent backflow when the feed pump is not in operation.
In practice, the names check valve and non-return valve are used interchangeably because of the similarities they share. Both valves allow flow in only one direction; however, there is a fundamental difference between them. A non-return valve takes up either a fully open or fully closed position depending on the inlet pressure of the fluid. Whereas the check valve offers a range of flow rates depending on the inlet pressure of the fluid. Thus, it is safe to say that a check valve is a subset of non-return valves that offers flow regulation.
When dealing with different fluid control systems, backflow is a serious issue that can lead to significant problems. When fluids or other media flow in the wrong direction, it can damage equipment, contaminate clean fluids, reduce work efficiency, and create serious safety hazards. For example, in water treatment facilities, backflow can cause serious health risks by contaminating drinking water. In HVAC systems, backflow can cause corrosion by mixing air and water. In your own home, backflow can be the reason your pipes are banging when you turn on the water.
Luckily, there is a simple, and inexpensive, solution to preventing problems caused by backflow&#;
Check valves are crucial components in fluid systems to prevent backflow. They act as a one-way gate that only allows media to flow in the desired direction, while blocking any reverse flow.
If you want to learn more, please visit our website Ductile Iron Ball Check Valve.
The basic operating principle of a check valve is simple, yet effective. As fluid flows in the intended direction, the valve opens and allows it to pass through. When the direction of the media reverses, the pressure causes the valve to automatically close, creating a seal to prevent backflow.
There are different types of check valves. The two most common types are vertical/spring check valves and swing check valves. Both types are highly effective in preventing backflow and keeping media flowing in the proper direction.
A swing check valve contains a hinged disc (or flapper) in the valve body. With little pressure from the media flowing against it, the disc swings open to allow it to pass through in the intended direction. Once the media flows in the opposite direction, the pressure presses the disc back to create a seal.
Spring (in-line) check valves use a spring mechanism to close the valve when flow stops. Spring-loaded check valves are powered by flow and differential pressure, like the swing check valves, but with added assistance from spring pressure. The spring holds the valve disc closed until forward (cracking) pressure overcomes the spring force, which then allows flow. When the pressure drops, the spring reseals the valve. The operating function of this type of valves allows them to be installed in any orientation.
Both types of check valves are incredibly reliable and require minimal maintenance, making them a cost-effective solution for backflow prevention. Their automatic operation does not require oversight, and can save companies and homes a fortune on the damage they prevent.
The primary purpose of a check valve is to prevent backflow. Doing so protects equipment, prevents contamination, helps maintain system pressure, and prevents water hammer.
Backflow can be devastating to equipment within the system such as pumps, compressors, and other mechanical components. When fluids flow in the wrong direction, they can cause excessive wear, damage seals, or even lead to failures within the system. Check valves are a safeguard that protects this equipment from the harmful effects of backflow.
In systems where different fluids are involved, backflow can inadvertently lead to the mixing of these fluids. This kind of contamination can be a nightmare for industries like food processing or pharmaceuticals where fluid purity is required. Check valves are used to prevent treated water, chemicals, or other substances from flowing backwards and mixing with untreated or incompatible fluids.
Check valves also help maintain system pressure by preventing the loss of fluid due to backflow. This is an important feature for applications where consistent pressure is essential, such as HVAC and irrigation systems
Check valves are also an important tool used to help mitigate water hammer. Water hammer results from a water pressure surge in your pipes, often occurring after an abrupt direction change, burst from a previously clogged pipe, or a sudden valve shutdown from within the plumbing system. Installed check valves allow a more controlled deceleration of the fluid flow when a valve closes, dissipating the kinetic energy of the moving liquid. This energy dissipation helps to mitigate the effects of water hammer.
Check valves are widely used in industrial settings as well as residential. Here are some common applications where check valves play a critical role:
In residential plumbing, check valves prevent contaminated water from flowing back into the clean water supply, which could otherwise introduce harmful bacteria, chemicals, or contaminants into drinking water. They're also used in irrigation systems to keep water flowing to crops and lawns without backflow into the main supply. In wastewater treatment plants, check valves prevent sewage from backing up into homes and businesses, which is a big deal for obvious reasons.
Manufacturing, chemical processing, and power generation industries rely heavily on check valves. They protect pumps, compressors, and other equipment from backflow, saving companies from expensive repairs and downtime. Check valves also play a vital role in maintaining pressure and preventing contamination in these complex systems.
In heating, ventilation, and air conditioning (HVAC) systems, check valves prevent the reverse flow of air or water. Heated and cooled air can then be delivered to the intended spaces as the water circulates properly through boilers and chillers. This prevents damage to components and helps optimize the system to maintain the desired temperature and pressure levels without disruptions.
Check valves find use in countless other applications, including:
Need a check valve fast? We have thousands of check valves in stock, ready to ship, and can get your order out the door by the next business day, with fast shipping options available. Have questions or need help selecting the right check valve? Our valve experts at ElectricSolenoidValves.com are here to help via , , or chat during business hours. Leave us a message after hours, and we'll get back to you promptly the next business day.
For more Types Of Air Valvesinformation, please contact us. We will provide professional answers.
If you are interested in sending in a Guest Blogger Submission,welcome to write for us!
All Comments ( 0 )