What guarantees the sealing performance of check valves?

What are the unknown secrets to the sealing performance of check valves? In the "arterial network" of industrial fluid transportation, check valves are like stubborn "gatekeepers", firmly blocking the medium that wants to run back - but did you know? Its unwavering confidence has never come out of thin air.

First, let's talk about the core 'tacit partnership': valve disc and valve seat. If these two components don't match properly, even the most powerful check valve will be useless. I have seen many high-quality valves, and from the design stage, I have been competing with this "partner", polishing every step of the process. The final contact surface is so smooth that it can reflect the figure, and the flatness is precise to the micrometer level. As soon as the valve is closed, the valve disc seems to grow on the valve seat, tightly fitting and unable to even breathe. Last time I looked at the pipeline transporting hydrochloric acid in the chemical plant, I relied on this "partner" to withstand the corrosion. If it leaked, the consequences would be unimaginable.

Let's talk about the spring hidden inside again. Don't be fooled by its thinness, it's actually the 'hard bone' at critical moments. When the medium flows along, it relaxes and helps the valve disc open easily; As soon as the medium was about to turn back, it immediately straightened up and "snapped" the valve disc back onto the valve seat, and the sealing effect immediately improved. Let's talk about the water supply pump in the community. It's common for the water pressure to fluctuate. Thanks to the clever force of the spring, the check valve can stabilize the situation and prevent the water from flowing back and damaging the pump.

There is also the choice of sealing materials, which is a skill of "watching the medium before cooking". The temperament of the medium is different, and the material must also change accordingly. The valve that transports steam needs to use materials that can withstand several hundred degrees of high temperature, otherwise it will become soft when baked and the seal will become empty talk; If you come into contact with a strong acidic and alkaline "hot tempered" medium, you need to replace it with a corrosion-resistant material, otherwise it won't be long before it is bitten and riddled with holes. I went to a pharmaceutical factory a while ago, and they used a check valve for transporting alcohol, which was sealed with an organic solvent resistant gasket. After more than two years of use, it still looks like new.

Ultimately, the sealing performance of a check valve is never achieved by a single component working alone. It is the tight fit between the valve disc and the valve seat, the cleverness of the spring, and the appropriate sealing material that together make this "gatekeeper" stand steadily in every shift in the harsh environment of high temperature, high pressure, and strong corrosion.