I have connected a 200 bar helium tank and a manometer to a pressure regulator. The end of the manometer's tube connected to the regulator is leaking. It's attached with anaerobic thread sealant, so I can't remove it.

Here is the video of the connection

It leaks between rotating and non rotating parts

enter image description here

I tried using bath sealant, but it doesn't sustain 200 bar. I also attempted sealing it with melted soldering wire, but it doesn't stick, no matter how much flux I use. I need some kind of sealant, that is tough enough, but aerobic

The tube is guaranteed to sustain up to 300 bar, but apparently it doesn't.

How do I fix the leakage?

  • $\begingroup$ It will be very difficult to seal this from the outside. Are you able to remove the pipe and apply the sealant on the inside surface? $\endgroup$
    – jpa
    Dec 14 '16 at 7:10
  • $\begingroup$ I thought about it. What sealant do you suggest for sealing from inside? $\endgroup$ Dec 14 '16 at 7:51
  • $\begingroup$ I don't mind if the tube is completely sealed afterwards $\endgroup$ Dec 14 '16 at 7:52

For high pressure connections it is common to use self sealing connectors with either tapered thread or dome shaped seats, in the second case it is not the thread itself which provides the seal. So the first thing is to verify what sort of connector you have as applying sealant to a seated connector can actually stop if from sealing properly and the mating surfaces need to be scrupulously clean.

Here the role of the thread is to tighten the seats together and the fact that the whole thing can rotate implies that it isn't tight enough or that the fittings are incompatible.

Do you have a link to the original product ?

Either way the chances are that you are going to have to disassemble the connection as you are unlikely to get a good seal now without cleaning it just applying more layers from the outside never works. You can usually remove anaerobic sealant by applying gentle heat.

  • $\begingroup$ It's either this one or similar opensea.ru/manometr-a25648.htm?s=price It leaks not from the part connected with sealant, but the one above it (which is rotating) $\endgroup$ Dec 14 '16 at 10:54
  • $\begingroup$ It looks like there is an internal seal which is compressed by tightening the thread. In this case the thread itself doesn't contribute to the seal but just keeps the internal seats tight together. This example illustrates it more clearly hoses.co.uk/adaptors-and-fittings/brass-hose-tails/… $\endgroup$ Dec 14 '16 at 11:00
  • $\begingroup$ What do you mean by "seal which is compressed by tightening the thread" Can I tighten it in some way, to make it sealed? Or is it broken by tightening? I tried rotating, but it rotates absolutely freely. $\endgroup$ Dec 14 '16 at 11:12

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