Replacing the packing on a low-temperature stop valve
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How to replace the packing on a DN100 low-temperature stop valve (medium pressure: 0.2 MPA)? After closing the valve, loosen the gland – can it be replaced online?
Hello, based on our experience, it is possible to replace the component online, whether the valve is closed or fully open. Since most low-temperature globe valves have a dual-sealing mechanism, the replacement is done ring by ring; for those without any access points, it is necessary to shut down the system in order to carry out the replacement by removing the actuator
In the case of a low-temperature gas valve, at a pressure of 0.2 MPa, it is recommended not to replace the packing; instead, simply loosen the packing gland and add an appropriate amount of Teflon tape as a substitute for the packing. Be sure to avoid the use of oil. If it is a cryogenic liquid, it is best to continue using it ； To proceed with the treatment, the valve must be closed and the liquid drained from the drain valve before packing can be added. Additionally, if the packing used in low-temperature valves is a PTFE \"O\"-ring, it is best not to replace it by cutting it, to avoid leaks. Remember, never work with liquids under pressure – safety first. (For reference)