Chromatography Forum

AT work I have been tasked with getting a HP 5890 series II GC up and running. I have some experience in analytical chem (more than the other chemists in my lab), but I haven't done GC before. Mostly I have been muddling my way through, with help from the internet and the manuals.

The problem I face at the moment is finding a column nut for the detector end. Inlet side, I put a column nut into the reducing nut and it fits ok. I have not played with the actual column yet. On the detector end, I have a thread that will fit a reducing nut but then there is 12mm of the FID jet poking out - this then prevents insertion of the column nut. I guess this is the correct config for the FID? That is how I received it.

I have a broken 5890 to harvest for spares, but that doesn't have any detector and the adaptors on it do not fit a reducing or column nut.

What I need help with is, does anyone know a adaptor or column nut for the detector end of this GC? Or am I missing something .. ? When I watched a how-to video, the fittings did not match what I see on the detector end of my GC, gut feeling is I will need to order more parts but I don't know what!

Many thanks!

If it's stock Agilent parts you need #5181-8830 (column nuts for both inlet and detector) and short ferrules like #5062-3514 ( these are for 0.32 columns).

Thanks, that looks like the column nuts I already have that don't fit... I haven't tried with the ferrule in (one step at a time) but I can't think how that would make a difference.

Sounds to me like you have a hardware mis-match.

Can you take some good clear photos and upload to something like photobucket.com, then paste the link here so we can see what you have, that would make things easier.

An FID jet for a packed column is longer than an FID jet for a capillary column, and the capillary jet hole will be wider so a capillary column can actually feed up into it. Also, the FID stainless steel liner for packed column use will be longer, and will have an external male thread that a 1/8 inch SwageLok nut will thread onto. A capillary FID stainless steel liner will have internal female threads of 6.0mm x 1.0mm.

There are different sort of column nuts that go with different ferrules. The typical column nut needs a short ferrule as stated in an earlier response. I also have a nut with a scratch line through the wrench flats that accepts typical graphite vespel ferrules that you would use on a MSD only the pointed end of the ferrule goes towards the detector.

Finally 5890 FID has an adapter that allows you to use a capillary column rather than a packed column. The adapter screws into the detector with a 1/4" graphite vespel ferrule and a steel nut and at the bottom it has the threads and mating surface for a capillary column nut and ferrule.

Thanks all, I appreciate you taking the time to respond to me. I have got some pictures but all hosting sites are blocked from work. I will post from home over the w/end.

I took out the FID jet and measured it - 63.5mm which I believe is for packed columns. So I have ordered the correct jet to use with capillary.

Finally 5890 FID has an adapter that allows you to use a capillary column rather than a packed column. The adapter screws into the detector with a 1/4" graphite vespel ferrule and a steel nut and at the bottom it has the threads and mating surface for a capillary column nut and ferrule.

I would appreciate more info on this, please. Having another look today I am reasonably confident I can bodge a solution with the bits I have, but I am wary to do that with kit that could fill my lab with hydrogen...

Is there meant to be some sort of liner on the FID? There does not appear to be one on mine.

http://www.restek.com/catalog/view/651
This one has everything you need and works better
http://www.restek.com/catalog/view/650

here you go. The tube part slips into the FID and you put a 1/4 graphite vespel ferrule and steel nut on it. The column goes through the middle of the adapter and into the jet and a column nut and g/v ferrule seals it.