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Pressure decay leak test standard

Discussion in 'Sampling, Standards and Inspection' started by bkirch, Aug 8, 2023.

  1. bkirch

    bkirch Active Member

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    For a pressure decay leak standard, could someone explain, in laymen terms, what this standard is saying?

    "There shall be no single leak path larger than the equivalent hydraulic diameter of an 115 micron sharp edge orifice conforming to ASME MFC-3M-2004 certified to 100 cubic centimerers per minute (CCM) plus or minus 20 degrees C air at 103 kPa gauge pressure(200 standard cubic centimeters per minute - SCCM) in area where casting is exposed to non-pressurized"
     
    bkirch, Aug 8, 2023
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  2. Andy Nichols

    Andy Nichols Moderator Staff Member

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    It looks like the verbiage is truncated about the UUT casting...

    If I understand leak down testing, this spec calls for a standard - the 115 micron etc - under those air temp & pressure conditions which will provide a specific leak down (pressure drop) over time. So, if you take a test casting (as described) the pressure drop/time at the porosity site (single leak path) will be less than the standard 115 micron orifice - by comparison.
     
    Andy Nichols, Aug 8, 2023
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  3. Andy Nichols

    Andy Nichols Moderator Staff Member

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    Andy Nichols, Aug 8, 2023
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