Carolyn and others, Having used lines built by others, but never having built one myself, I need to take advantage of your experience... For the Kel-F vessels, are you using stainless steel or teflon ferulles [sp?] with the swagelok fittings? Thanks to all for the information on wall thickness/internal diameter. Obviously a sturdy wall is needed. In general, what type of ferulle is recommended with metal-to-metal swagelok connections--teflon or steel? ****************************************************************** >Steve, >Our Kel-F tubes have been drilled to 5/8 internal >diameter, i.e. 3/16 wall thickness. We are using >Swage-lok fittings, and it is important to have a good >wall thickness. >Good luck with your line >Regards, >Carolyn Chenery > >NERC Isotope Geosciences Laboratory >Kingsley Dunham Centre >Keyworth, Nottingham UK NG12 5GG >Tel : +44 (0)115 9363100 (Switchboard) >Tel : +44 (0)115 9363406 (Direct Line) >FAX: +44 (0)115 9363302 >e-mail [log in to unmask] ******************************** Steve Nelson Dept. of Geology 673 WIDB Brigham Young University Provo. Utah 84602 voice: 1-801-378-8688 FAX: 1-801-378-8143 "INTEL INSIDE" is a warning label *********************************