Helium leakage:
Helium is a very rare gas found on the earth and it is believed that it is going to be depleted in 2030. So, It is our duty as cryogenics engineering people to save as much helium as possible we can. We need to look for the leak from the cryogenics system which involves the use of helium as a working gas.
A leak from the system also causes poor vacuum conditions. So, we need to rectify that leakage and try to save helium. Normally any pressurized Helium gas system is not 100 % leak-proof and one’s aim is to detect this leak as early as possible and try to solve this.
How to Operate a Helium Leak Detection System?
Here is a standard procedure to use Helium Leak Detection System.
The helium leak detection system consists of a turbo molecular pump which helps us to detect the helium gas leaking from the system. The connector is the place where the sniffer probe is attached with the proper cable and is directed to the leaking point at the system and this probe detects the leaking helium at a millibar per second rate.
Normally away from the leak point, Helium Leak Detection System detects helium from normal air as it contains helium too and it is of the order of 10-6 millibar per second. When the sniffer probe detects helium at the leak point, its reading will increase from 1E-06 to 1E-04 or more depending on the leak rate. Here is the procedure to operate a Helium Leak Detection System
- First, make sure the sniffer probe is attached to the Helium Leak Detection System (System)
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Do the calibration for the system after about 3 months.
- Switch ON the system and it will show STAND BY mode
- Run the system for 20 minutes and then press the Calibration button (When you want to calibrate the system)
- Select the Internal calibration option.
- When the system returns in STAND BY mode, make sure that the sniffer probe is attached to the system.
- Start the leak detection and make sure sniffer probe is open to an atmosphere where the leak is to be determined
- Away from the leak point, reading will be in terms of 10e-6 due to helium presence in the air and when there will be any leak detected, it will be more than 10e-6, i.e. maybe 10e-4,10e-3 mbar/sec
- After completion of leak detection, press the STOP button, and the system will be returned to STAND BY mode
- Press Vent button
- Put blank in place of sniffer attachment.
- Start t Gas ballast after 10 min
- Switch off the system
Note: Do not move the system in while it is in hot condition.