HI, I had just tossed out all the mail associated with this topic and found something in a magazine. I am looking at the current issue of "Cleanrooms" (Feb. 2001) and ther is an article on Leak Testing of cleanroom equipment and clothing. It suggests a fixture and compressed air. Hope this helps. Chuck Brummer Acuson Brian Ellis wrote: > Don, > > I don't know whether it is applicable to your application, but a > traditional method is to immerse the part to be tested in a hot fluid > (say 70°C) and observe for bubble streams. The choice of fluid is > difficult. It must have a low surface tension and low viscosity; it must > be stable with time at the chosen temperature; it must not evaporate; it > must not be reactive with anything on the assembly; it must not affect > the electrical properties; it must be easy to clean off; it must be > cheap; it must not pollute; it must be non-toxic and non-flammable; etc. > Unfortunately, this miracle liquid does not exist but there are some > which come quite close. These are perfluorocarbons. They fill these > functions bar two: they are polluting and they are damned expensive. In > this application, the expense part can be minimised by good housekeeping > and recovery of drag-out losses. Notwithstanding, there will be losses > due to evaporation and these products are amongst the most > global-warming substances known to man, about 10,000 times worse than > CO2. This means that 1 kg lost is equivalent to 10 tonnes of CO2 and 10 > tonnes of CO2 may be produced by burning 16 tonnes of motor fuel, which > is equivalent to about 20,000 litres, sufficient to run a modern car > 200,000 km, or more than the average lifetime of a car. See what I'm > getting at? Recover every milligram you can. That having been said, I > guess you may be in Deutschland and there may be regulations regarding > the use of PFCs in your country, either in force or proposed. Check > carefully. > > Hope this helps. > > Brian > > "Steffen, Don E" wrote: > > > > Technetters > > > > I am a Quality Engineer on a Safety Product that has a Leak Test > > requirement. We are using a die cast aluminum housing that has a > > porosity issue. I want to find out if there are any one in the TECH > > NET world that might have some experience in leak detection methods. > > Water is out of the picture. Because of the vertura effect, water can > > be sucked into a housing. I am presently using water for > > troubleshooting purposes, but everything that is applied to water is > > scrap. I have tried Helium gas but this is not always reliable and > > repeatable. Is there anyone out there that can help me out in this > > dilemma? > > > > ----------------------------------------------------------- > > This Mail has been checked for Viruses > > Attention: Encrypted Mails can NOT be checked ! > > > > *** > > > > Diese Mail wurde auf Viren ueberprueft > > Hinweis: Verschluesselte Mails koennen NICHT geprueft werden! > > ------------------------------------------------------------ > > --------------------------------------------------------------------------------- > Technet Mail List provided as a free service by IPC using LISTSERV 1.8d > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet > To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL > Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional > information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 > --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------