Questions regarding helium mass spectrometer leak detectors
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Our company manufactures high-pressure U-tube heat exchangers with a design pressure of 32 Mpa. We plan to conduct helium leak testing on the welds at the tube ends on the tube sheet. Currently, we are in contact with products from Hefei Wanyi Technology. We would appreciate everyone’s insights on whether this is an appropriate approach. It would be great if anyone who has used a helium mass spectrometer for leak detection on similar products could share their experience. This post was last edited by Da Hu on 2007-11-27 at 10:25
We use German ones; I forgot the model number. They are used in urea equipment.
For the leak testing of the tube ends in the heat exchangers we manufacture, helium leak detection is primarily used; however, the helium leak detectors employed are of Japanese origin and have high precision. I’m not sure what the leakage threshold you require is?
Which area is the unit on the third floor in? I’m in Taizhou, Jiangsu. If it’s not too far, shall I go and take a look?
It’s impossible to do that; there are rules. :Lol, but if there are any issues, we can communicate.
Is a suction gun used? Is the shell filled with helium?
Generally, helium is introduced into the shell side for leak detection. If the suction gun method is used, the precision cannot be required to be very high, and the error is relatively large. If high precision is required, it is best to use the negative pressure method.
But with such a large housing, what size vacuum pump will be needed? I remember there are relevant requirements specified in ASME – could you let me know your standards?
The negative pressure method refers to evacuating the tube side, rather than the shell side.
It’s unimaginable; could you explain the process in more detail?
Push the tube bundle into the shell, and assemble the tube box with the tube bundle. Vacuum the pipe section again.
Where is helium present during leak detection?
When the vacuum in the tube side reaches a certain level, turn on the helium leak detector. The helium in the shell side will rise to the tube side, at which point the helium leak detector can detect the concentration of helium in the tube side. Helium leak detectors using this method are equipped with a vacuum pump and an ion separator as well, which results in high detection accuracy; such devices cost hundreds of thousands.