What are check valves?
Check valves can be found in practically every industrial application, acting as one-way flow or non-return valves. It’s a very popular part of industrial usage. Most of these kinds of products are made by China check valve manufacturers.
Check valves are primitive devices and can also perform an essential function by stopping reverse flows, thus preventing damage and making sure that operations are carried out efficiently. As an example, the reverse flow may result in pressure loss. This occurrence is due to extreme pressure in a pipeline system, valves and pumps might destroy or disturb the system and the whole system. Even if such a failure does not happen immediately the consistent and negative impact of the water hammer can permit fatigue that will ultimately result in a loss of pipework integrity.
Featuring a singular inlet and outlet, check valve are operated by pressure difference. Above a certain upstream pressure, the check valve will be compelled to open without the need for any other intervention. Better known as the cracking pressure, this small operational pressure is one of the primary characteristics found in all check valve. Chemicals, pulp, paper, food processing, water, wastewater treatment, industrial, marine, mining, pumps, pipelines, power generation, and HVAC (Heating, Ventilation, and Air Conditioning) are among the many liquid flows and pumping applications that also include check valves.
Usually, check valves are positioned in a series, for example, in water systems to stop the backflow of contaminated water into clean supply lines using a huge variety of potential applications. In these applications, there are also multiple different types of check valve, which utilize many different materials such as different metals, polymers, and rubber. Frequent designs include flap or swing check where a metal disc pivots on a hinge or a pivoted valve to prevent fluids from flowing backward. Where a metal disc pivots on a hinge or as the name hints, ball or spring check valves comprises a ball that is mounted on an appropriately profiled seat. Duckbill check valve always rely on a flexible rubber diaphragm which makes a valve that is usually closed unless positive pressure is applied.
However, dissimilar to their metal swing or flap check valve counterparts rubber duckbill check valves cannot bind, seize or rust, normally increasing longevity and durability. Likewise, rubber check valves do not suffer from this damage, a variable that can greatly impact check valves manufactured from other materials.
Choosing quality check valves
When specifying check valves, many variables must be considered to confirm the correct choice. To be specific, it is important to make sure that any check valve are manufactured from suitable materials that are compatible with the fluid that is used during the hypothetical operation, e.g using a rubber duckbill check valve where they are appropriate. Valve rating, line size, type of installation in either vertical or horizontal, connection type and dimensions, pressure drop, leakage rate, and any special needs should all for part of an in-depth investigation. It should also be noted that you will need to ensure that the correct type variant of the valve is used in each application. Good check valves have to reach the requirements of what you need, so always remember these two factors:
- Durability
- Effectivity
Read also the difference between Choose or Chose