How Helium Leak Detection Works
Helium is used as the tracer gas in many leak detection operations because it is inert and non-flammable. The gas is also non-toxic and cannot be condensed. Because of its exceptionally small molecule size, it can pass through tiny holes.
A mass spectrometer leak detector (MSLD) is the equipment used to find and measure leak sizes. The helium is applied to the part to be tested. Thedetectoris connected to this section. Where thechemical element seeps through a hole, it enters the system where the pressure is assessed. The results of the measurement are displayed on the detector metre.
The system consists of a spectrometer that detects the helium mass, a vacuum section that keeps the pressure in the spectrometer and a mechanical pump that evacuates the test part. It also includes valves that help to control the detection phases, such as the test part evacuation, test, and vent operations. Furthermore, it has controls and power supply parts.
Method for Detection
A pressure test from the inside-out or a vacuum test from the outside-in is performed to test the parts. The method applied depends on the operation condition of the test part. The pressure condition during the test must be kept the same as when the test part is in operation.
When a vacuum system is tested, it is imperative to have a vacuum in the test part while high pressure must be maintained inside the compressed air cylinder while it is tested. With the inside-out method, a mixture of air and helium, or only helium, is used to pressurise the test part. A sniffer probe is connected to the detector equipment and is then used to scan the test section for possible leaks. A pump system is used for evacuating the test part with the outside-in method. The helium is applied to the section where a leak is suspected. This is done through the use of a probe that sprays the helium.The flow can be adjusted according to the requirements for the particular application.
Where and When to Use Helium Leak Detection
It is used for quality control purposes to test the integrity of the various processes such as vacuum systems, fuel lines, condensers, and heat-exchange systems. It is also used as part of system maintenance where periodical leak checks must be performed or instances where the cause of system failure must be determined. It is used in pressurised systems such as power plants, underground pipes, and liquid gas systems. It is also used for the detection of holes in vacuum furnaces and coaters, to name only a few of the application areas.
What We Offer
We offer high integrity nitrogen and helium leak detection of tanks, heat-exchangers, and process systems where there is a risk of small leaks at the starting up of these systems. Any such issues can lead to system failure or can cause a hazardous situation. Such systems include LNG and ethylene to cryogenic systems.