Regarding the issue with the valve cores in the ammonia station
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This post was last edited by 1025199692 on 2016-4-17 at 13:56. The valves that are frequently in use in ammonia systems (gas phase/liquid phase) occasionally experience ammonia leakage from their valve cores. Usually, a repair technician comes to replace the packing and tighten it, but the same problem arises again after a few days. Has any friend encountered this? How did you all solve it?
Is it internal leakage or external leakage? The packing causes external leakage, while the valve core causes internal leakage.
Frequent opening and closing of the valve can cause wear on the packing; too high a roughness of the valve stem can also lead to wear of the packing. Additionally, improper use of the packing, which lacks wear resistance, or bending of the valve stem can result in leaks. Take appropriate measures based on the above situation.
What filler is better to use?
Corrosion of the valve stem and rough surface texture cause packing wear and ammonia leakage
Thank you! It seems the only option is to replace the valve.
There are too many types of packing materials; the best ones include aramid fibers (used in body armor and likely very expensive). Commonly used materials include carbon fiber packing, PTFE packing, graphite packing, and graphite ring packing.
Our company uses PTFE packing, and there have been no instances of ammonia leakage due to the packing. Are your valves opened and closed frequently?
Well, the valves are used very frequently and move often.
For valves that are adjusted frequently, why not replace them with a better pneumatic diaphragm control valve? This would reduce the workload and enhance intrinsic safety