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  1. ajdowdell

    Valve flow testing suggestions?

    How long duration are you wanting to hit those flows? Air or water? I'm thinking you're going to want large storage tanks and compressed air storage. 200 psi should be no big deal you can buy tanks for that all day long. you could get away with a smaller pump let it run over night then...
  2. ajdowdell

    cm^3/s to ppmV

    "In the case of Helium in air, for example: 1 ppmV = 1 ml/m3 = 0.176 mg/m3 = 0.136 mg/kg = 0.136 ppmM 1 ppmM = 1 mg/kg = 1.29 mg/m3 = 7.32 ml/m3 = 7.32 ppmV(please double-check against other sources, if you like...)" I haven't found any sources yet, but does this assume atmospheric...
  3. ajdowdell

    cm^3/s to ppmV

    GOOD, GOOD, GOOD! I like it when a plan comes together, and everyone is on the same page! Its good to see these as well, I will double check just to make sure... 1 ppmV = 1 ml/m3 = 0.176 mg/m3 = 0.136 mg/kg = 0.136 ppmM 1 ppmM = 1 mg/kg = 1.29 mg/m3 = 7.32 ml/m3 = 7.32 ppmV...
  4. ajdowdell

    cm^3/s to ppmV

    "In his second post he mentions that calculating ppm is simply computing a ratio of flow rates." He must have left off the "V" then because--> "If you perform a deeper search, you'll find leak detectors that also give readings in ppm (especially portable instruments); besides, it's only...
  5. ajdowdell

    cm^3/s to ppmV

    The Varian 959 does not have a built in Helium leak, but we have it calibrated very frequently, and it's expensive! Since this is true: -->So why doesn't taking measured helium volumetric flow rate divided by the total volumetric flow rate, not give ppmv? Am I confused about anegri's first...
  6. ajdowdell

    cm^3/s to ppmV

    I would prefer to use our current varian 959 if at all possible... yes it is concentration but by volume. Not a mass or molar concentration which is the normal ppm designation and why they are so specific as to require units in ppmv not ppm. most testers read in cc/s, and that is a volume per...
  7. ajdowdell

    cm^3/s to ppmV

    The problem with all of that though is that ISO call for ppmV (volume) NOT concentration. They are VERY specific that it is volume, not actual ppm. I am primarily interested in doing ISO 15848-2 and the SHell spec, the -1 ISO is beyond the scope of prodution testing. the -2 ISO only...
  8. ajdowdell

    cm^3/s to ppmV

    I think classify basically means pass/fail. I wonder if ours has a calibrated oriface, I think that would require a pretty constanct vaccuum to be applied, so the operator would have to be careful to maintain the required distance. Last time I checked our probe had a short section of polypro...
  9. ajdowdell

    cm^3/s to ppmV

    I'm thinking you would have to quantify the flow rate that is being pulled through the sniffer. Once I knew that rate, I could use the cc/min rate given and basically divide the two and get a percentage (probably in the ppm range) and the per seconds would cancel out leaving volume/volume...
  10. ajdowdell

    cm^3/s to ppmV

    So it says that it is to "classify" leaks only not quantify... But how do I use a device that measures in atm*cc/s to classify?
  11. ajdowdell

    cm^3/s to ppmV

    Here's their wording in the description of the sniffing method: A portable instrument is used to detect leaks from valves. The instrument detector type is not specified. But the selected detector and its sensitivity shall be able to meet the tightness class limits. This procedure is intended to...
  12. ajdowdell

    cm^3/s to ppmV

    I would prefer to do the sniffer method for everything as it's difficult to encase the valves we build because they cover just about every size/pressure class/actuator known to man.
  13. ajdowdell

    cm^3/s to ppmV

    ISO 15848-2 the production test does not specify a casing at all. The -1 ISO spec has several different methods. 1. Vacuum method-- sealed chamber is evacuated, then the valve is allowed to leak, the device pulls the helium through it. atm*cc/s or Pa*m^3/s 2. flushing method-- the sealed...
  14. ajdowdell

    cm^3/s to ppmV

    OK, now I have a varian 959 manual mass-Spectrometer. it measures in atm*cc/s. I know the discussion that cam about before you could not convert between atm*cc/sec and ppm, but where doesn ppmV fall into this? It means part per million of volume. Basically the end goal is this: I want to...
  15. ajdowdell

    cm^3/s to ppmV

    Ok, so I work at a facility building valves. I'm being asked to meet differing fugitie emission standards. there are 3 that I know of, and I'm trying to get a handle units of measurement. I think this has been sorta hashed out before on here, but the thread was closed. The 3 standards I'm...

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