LEAKLAB · TESTING AND ENGINEERING
Tracer gas is introduced inside the object and a sampling probe surveys external joints and surfaces.
How the inspection works
The product contains helium or the agreed tracer mixture under an allowable pressure. A probe samples the surrounding atmosphere along a defined route. Helium leaving a through-defect is transported through the sampling line to the detector.
Probe distance, movement speed, local dilution, gas concentration and sampling-line response must be controlled. Sufficient dwell time is established by a response check, rather than chosen only for operator convenience.
Interpreting the instrument specification
A detector’s vacuum-mode sensitivity is different from its sniffer performance. The usable sensitivity is verified in the actual sampling configuration. Pressure and gas compatibility are agreed from the object documentation; an excessive test pressure is not justified by the desire to produce a larger signal.
Preparing and verifying the test
- Review the drawing, materials, internal volumes, test boundary and required result.
- Agree the document edition, allowable pressure difference, vacuum and temperature, acceptance criterion and required system sensitivity.
- Clean and dry the object, prepare fixtures and exclude leakage from the test connections.
- Check instrument metrological status and the working characteristics of the complete arrangement; use an appropriate reference response for the selected method.
- Perform the agreed scan or measurement cycle and record the actual conditions. Confirm suspected leaks by repeat tracer-gas exposure where applicable.
- Check system stability after the test and report the result against the agreed criterion.
What the customer receives
The agreed scope can include a test programme, operating or inspection instructions, measured results, a map of located leaks and a technical conclusion. The report identifies the object and tested regions, applicable programme, instruments and metrological status, pressure and temperature, response checks, observations and limitations.
Define your task
Send a drawing or sketch, material, dimensions and volume, working pressure, allowable vacuum and temperature, leak-tightness requirement, number of items, site and schedule. These inputs determine the method, fixture, equipment and reporting scope.
Discuss a test programme