Lecktest

Lecktest, literally meaning "leak test" in German, designates a non-destructive testing method used to determine whether a closed system, component, or container exhibits leaks or can withstand a specified leak rate. The test typically involves applying a reference pressure or vacuum, then monitoring for a pressure drop, a rise, or the appearance of escaping gas or liquid. Detection can be accomplished directly via sensors, acoustics, or visual observation, and may also use tracer gases or liquids to locate leaks.

Common methods include pressure decay, where a known pressure is applied and the time-dependent pressure change is measured; pressure rise, where the system is pressurized and the rate of pressure increase is monitored after sealing; vacuum decay, where a vacuum is applied and its maintenance is observed; bubble tests, where the device is immersed or wetted with liquid to reveal escaping bubbles; and tracer-gas leak detection, which uses a tracer gas (often helium) and specialized detectors to identify leaks. The choice of method depends on the size, geometry, operating conditions, required sensitivity, and the consequences of a leak for the application.

Applications of Lecktest span many industries, including automotive and aerospace for fuel, cooling, and hydraulic systems; refrigeration and air conditioning; pipelines and pressure vessels; medical devices and pharmaceutical packaging; electronics enclosures; and consumer products. It is used as part of quality assurance, safety compliance, and regulatory testing to ensure integrity and prevent product loss, contamination, or failure.

Practical considerations include selecting an appropriate method for the expected leak rate, ensuring proper calibration and sealing during testing, and accounting for environmental factors such as temperature and humidity. Limitations can include insufficient sensitivity for micro-leaks, permeation effects, and potential false readings if seals or fixtures are not prepared correctly.