Leak testing large volume automotive components –transfer cases, oil pan assemblies, reservoirs , intake manifolds, and transmissions, and the like– poses a different set of challenges than those of testing smaller parts.  Some automotive manufacturers have straddled their operations with antiquated pressure decay leak test methods for such large parts. Pressure decay, or differential pressure decay testing, is rarely a best match leak test method for large parts because the larger the part volume, the smaller the change in pressure for a given leak rate. With pressure testing, as you increase test volumes the result is inherently long test times AND increased measurement errors.
Using mass flow leak testing methods for large parts is always faster with acceptable gage R&R easier to achieve. However, a vigilant eye on how production rates are impacting the bottom line is compelling many manufacturers of larger automotive parts to ask – contact IDC for info……
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