. . . more ABOUT FERRULES 2014+ FlipPAGE5 . Price List 2016; (PDF)
Ferrules as used in the Chromtechs’ context . . .
Are leak-tight Pipe-fitting seals connecting Tube Fittings and various type of Tubing; SS, polymeric, glass ceramic , fused silica . . . in capillary and larger sizes; the latter being “fragile” and will just not sustain compression by metal ferrules
Metal ferrules normally used by Fittings OEMs such as Swagelok traditionally use metal with their obvious limitations
It’s not even in their pecuniary interest to even make OR re-sell Graphite Ferrules
Metal Once-off use - then you’re /they’re “buggared” !
Graphite Ferrules “slide-off” can be re-used many times but do tend to be “captured’ in the Nut if over-tightened
Applications include chromatography connections where gas-tight seals are essential both in positive pressure but also under high Vacuum such as GC/MS where the material used must be high purity and sustainable at up to 450degC nowadays
Common sizes range from (1/32, 1/16, 1/8, 1/4”OD with IDs tube size as small as 0.3mm up to 2.0”ID and larger for more exotic applications ? ASK!
AS far as we know we are the ONLY OEM of GFS with IDs larger than 1/2” . . . ANYWHERE !
In fact there are few OEMs who make GFS at all . Most Suppliers are in fact Distributors ONLY ( such as Agilent, Thermo, Shimadzu etc and AT MANY TIMES THE PRICE
Graphite Ferrules by FAR are the most Universally applicable
& where the Metal Ferrules are just NOT Good Enough !
FITTINGS OEMs DON’T necessarily like us > as GFs are reusable (with care) and easily slide off the tubing;
They are soft and malleable and deform to fit the shape of the fittings “internals” . . . and help to reduce dead-volume
They also have similar co-effs of thermal expansion as metal and will not leak under temperature cycling
There are virtually NO practical temperaure limits (but >450C as constraints impose by current Gas Chromatography practices and up to 1800C in an inert atmosphere)
Pressure Limits are at customers discretion ( Straight>> Reducing Type ) >100s psig size gas dependant
DONT USE with Hydrogen/Oxygen Air/ at High Temp >300c ?