Leak Testing (LT)

Helium leak mass spectrometer test is a way to detect very small leaks across a pressure boundary. 

Bubble leak testing is used to find leaks in many different components. The two most common forms of bubble leak testing are the direct-pressure technique and the vacuum-box technique. The direct-pressure technique is conducted by pressurising a component with a gas and then either submerging it in a solution or applying a solution to the outside of the component. If a leak is present, bubbles will form on the surface because of the leaking gas passing through the solution. The vacuum-box technique is conducted on parts that cannot be directly pressurised or where access is not available to both sides of a component. The test is conducted by applying a solution to an area of a pressure-boundary surface and creating a differential pressure across the area, causing the formation of bubbles as leakage gas, such as atmospheric air, passes through the solution.

The Halogen diode detector probe test is a method to conduct a leak inspection by using a tracer gas and a detector probe to detect the presence of halogen. The detection of halogen across a pressure boundary would indicate the presence of a leak.

Pressure change testing is conducted to determine the allowable leakage rate across the boundaries of a closed component or system at a specific pressure or vacuum. By monitoring the change in pressure over a period of time, the leakage rate can be determined, either by the loss of pressure in a pressurised system or through the increase in pressure in a system under vacuum. The change in pressure can then be compared to a maximum allowable change in either pressure per unit of time, percentage volume, or mass change per unit of time.