Rotating Equipment Issue - Pump

hi pradeep, thanks for the opinion. yes, i should rectify the issue on the HEx first, but it was not the option at the moment. medium for the pump is demin water in specific. my biggest worry is, is the any chance fire incident could happen if there is any presence of oxygen. the source of heat might come from the pump (friction, etc). for info, this is closed loop system.

The system must be shutdown to repair the HEX, it is easy to proceed a test for shell side without using a test flange, just dismantling the channel cover and it shall be easily by naked eye to see the leaking tubes, which can be easily plugged if its number within 10%, otherwise the tubes (bundle) can be repaired.

dear all, i required ur opinion. the tube side is the gas line at about 250 barg and at the shell side is cooling water at about 14 barg. the problem is, on the tube side, it will a left over a hard polymer.. its quiet difficult to find the leak. what is the best possible method as we are pretty sure by hydro test, leak test, chemical cleaning cant help us on the identifying the leak

"as we are pretty sure by hydro test, leak test, chemical cleaning cant help us on the identifying the leak"

How can you say that? Read the caption below the bottom line, it applies in your case too. If there is any leak, it can be identified. How the leak was concluded? I'm not familiar with this fluid, can you explain how hard polymer is allowing leak while in operation and not allowing when stopped.

If you are able to clean tube side by chemical cleaning and then hydro test (at 1.5 times the MAWP), leaking tubes can not hold the pressure even for few minutes.

hi all.

tube side: ethylene gas at a temp 150DC, press 250 barg

shell side:water side at temp 40 - 50 DC, press 14 barg

how hard the polymer.. even you used 30000psi HPWJ.. you still not be able to remove it. it sticky. at the moment, we can detect the presence of the hydrocarbon at shell side at the venting line of the water and the pressure on the suction line of the pump to deliver water for the shell side is fluctuating from 8-11 barg where it supposed to be at 8 barg. with the figure above, you can imagine how small the leaking is. i'm thinking to use helium / nitrogen gas to detect the leak? are you guys have any better suggestion? appreciate it.

You have not addressed my doubt directly "whether hard polymer is allowing leak while in operation and not allowing when stopped." As per your description polymer itself will plug the leak.

"with the figure above, you can imagine how small the leaking is"

No, With this information I can not imagine or assume that the leak is small. It can be appriciable also. For checking the leak nitrogen is as good as air (a little thinner gas). Helium detection unit (if you have) is for identification of extremly small leaks. but you should check leaks with the normal methods first. Can you take out tube bundle from the shell?

For such cases it is advised to keep a spare HEX and replace it with spare and attend the leak off-line.