Production Leak Detection Systems
This method involves measuring the pressure increase in a low-pressure area surrounding the part caused by escaping test media.
Since the pressure used outside the part is usually lower than atmospheric pressure, the temperature dependence is lower, therefore parts with temperatures other than ambient can be tested this way.
This method is especially suitable for testing particular areas of interest of parts (e.g. valve seats of assembled valves, covers, etc.) for leaks. The rise in pressure is only measured in the vacuum (or low pressure) area.
The test typically consists of the following steps:
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Establishing the desired pressure around the part |
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Charging the part to test pressure |
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Allowing the system to stabilize |
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Measuring the change in pressure outside the part |
The following illustration shows a typical pressure increase test:
The following table summarizes the main features of Pressure Increase testing:
| Sensitivity range |  |
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| Temperature dependence |
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| Operator dependence |  |
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| Main factors affecting accuracy |
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| Test pressure range |
high pressure applications |
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| Cost |  |
