Chromatography Forum

I need to hook up a headspace sampler to an Agilent 6850. I decided that the best bet is to cut the carrier line downstream of the EPC and use this to loop to the HS. Had a heck of a time figuring out which EPC line is the carrier vs. septum purge. Cut the one I was told to (the rear one looking at the inlet). Now I figure out this line is bigger OD and a 1/16" fitting won't go on it. It's approx 0.075" od, while the other line is approx 0.058". Now I'm not sure that I haven't cut the spetum purge.

Two questions:
1. Which line is the carrier?
2. Where can I get a fitting (union) to go onto the larger line?

Thanks

I see this link in another post http://www.chem.agilent.com/Library/use ... -90009.pdf. I guess I have cut the septum purge. Now I need to figure out how to get a union on this line. I guess if I get desperate, a file and a ton of patience might work. Hopefully, there's a better option.

You did cut the septum purge line, it is made of metric tubing, and if my memory is correct this is 2 mm tubing. You can get 2 mm unions and ferrules, not easy to come by but they are out there. Check with Valco and Swagelok, they do a lot of international business and may have the unions we need.

You found out the hard way what a lot of other people have also discovered the hard way, the best way to identify the carrier in line is that it is the smaller diameter line at the weldment.

Another option is to buy a new weldment from Restek, they are much less expensive than the equivalent Agilent part.

Here's the response from Agilent. I'm on the hunt for the 2mm fittings, although I managed to squeeze a LC union on it and it's working.


Cut the small line because the thicker one is the septum purge line.

SERVICE NOTE G1530A-103

Supersedes
None

Split Insert Assembly Carrier and Septum purges Lines have Changed

Service Serial Numbers:
US00000000-US99999999
CN00000000-CN99999999

The carrier and septum purge tubes are now reversed at the insert assemblies. No change in performance will be observed. When cutting the carrier line to add an external sampler you should always select the smaller i.d./o.d. tubing. The attachment indicates which is the carrier tube on original and newer insert assemblies. The change took place during early June, 2006.

Parts Required:

None

Situation:
During manufacturing insert assembly improvements, the reversal of the
carrier and septum purge lines at the insert assembly were made. Although no difference in performance should be observed with the tube reversals it is important for those users who are cutting the carrier line to add external samplers like the headspace. The smaller i.d./o.d. tube will always be the carrier in line no matter which vintage of insert assemblies. The part numbers of all assemblies affected are:

19251-60575 Split/splitless insert weldment w/tubing
G1544-60575 Split/Splitless Insert 6890 EPC
G1544-60585 S/SL Insert Weldment, w/Charcoal Filter
G1544-60595 BASF CAPILLARY INSERT ASSY.
G1544-60600 CAP INSERT ASSEMBLY
G1544-80580 S/SL Insert Weldment, for use with ECD
G1580-60575 6890 Insert Weldment, for valved systems
G1580-60585 Insert Weldment, valved system w/filter
G2630-61080 Vlv Inl insert assy


Solution/Action:
When adding an external sampler like the headspace only select the smaller i.d./o.d. tube which will be the carrier in line to the insert assembly.

Additional Information:


Date:
6/16/2006
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You can get 2 mm unions and nuts and ferrules from Swagelok, they are on the web site. Contact your local Swagelok dealer and see if they stock the parts or if this is something they will have to order. There may be a minumum quantity purchase required, but it will still be cheaper that replacing the weldment.

Been there done that, but ni t-shirt. The easy way to identify the carrier line is it's the one that attaches to the weldment via a flat spot just below the septa nut. I got burned when they reversed the tubes on me and I just cut the line at the front! I couldn't find a union so I just got another weldment via service contract.