replacement for flame tip ferrule varian 3800

[mr3573]

i am looking for a replacement for ferrule of flame tip (FID detector) for our CP-3800.originaly we could found two type of ferrule: Vespel or graphite (part numbers base on which ones we had are 89-999570-00 and 28-694570-00 respectively)so i searched in google to found that parts or their replacment but can not find anythings. the complete pack of flame tip is so expensive and we needs to ferrule only.any body know how can found that ferrules ?

[Peter Apps]

I think that you will find that an ordinary 1/8 inch ferrule in the material of your choice will do the job.

Peter

[WillyOne]

I agree Peter BUT take into account that there is a small metallic washer to be placed over the graphite ferrule. Do not loose it or you will be in troubles when using graphite ferrules.

Regards

[Peter Apps]

I agree Peter BUT take into account that there is a small metallic washer to be placed over the graphite ferrule. Do not loose it or you will be in troubles when using graphite ferrules.

Regards

Good point.


Peter

[mr3573]

thank your for replies. but in case of ordinary 1/8 ferrules, the flame tip will be positioned a little upper than usual.i tried to cut some of that in order to adjust place of flame tip. i want to try some standards ferrule and hope it available in market.

[Peter Apps]

thank your for replies. but in case of ordinary 1/8 ferrules, the flame tip will be positioned a little upper than usual.i tried to cut some of that in order to adjust place of flame tip. i want to try some standards ferrule and hope it available in market.

Changing the ferrule should not affect the position of the flame tip - before installation the ferrule can move freely on the tube below the tip, the bottom of the tube seats on the bottom of the port in the detector heater block, and then you tighten the nut. If it not working like this there may be something else wrong. Are you sure that there are no bits of the old ferrule stuck in the port ?

Peter

[mr3573]

I checked the difference of high between usual 1/8 Vespel ferrule and special ferrule of flame tip. High of usual ferrule is 7 mm while special ferrule is 5 mm. special ferrule I mean ferrule include in complete package of flame tip. So I should cut 2 mm of new one ferrules.

[Peter Apps]

No, do not cut the ferrule. The only effect of its extra length will be to make the compression nut sit a little higher. This will not affect detector performance.

[anamariboyes]

I have noticed that when using a regular 1/8" graphite ferrule, it doesn't fit snug on the flame tip and when trying to screw the nut back it, the flame tip does not catch or hold down.
I am having a similar issue and and trying to re-use the original ferrule since new 1/8' ferrules are not working out. Do I just need to force the nut with more strength for the ferrule to catch?
Thanks

[Peter Apps]

I have noticed that when using a regular 1/8" graphite ferrule, it doesn't fit snug on the flame tip and when trying to screw the nut back it, the flame tip does not catch or hold down.
I am having a similar issue and and trying to re-use the original ferrule since new 1/8' ferrules are not working out. Do I just need to force the nut with more strength for the ferrule to catch?
Thanks

That is the kind of question that cannot be answered over the internet !

How tight (turns past fingertight) are you making it now ?

Graphite is very soft and if you "force the nut with more strength" there is a chance that it will squeeze into the narrow channels that take air to the flame.

Peter

[anamariboyes]

I have noticed that when using a regular 1/8" graphite ferrule, it doesn't fit snug on the flame tip and when trying to screw the nut back it, the flame tip does not catch or hold down.
I am having a similar issue and and trying to re-use the original ferrule since new 1/8' ferrules are not working out. Do I just need to force the nut with more strength for the ferrule to catch?
Thanks

That is the kind of question that cannot be answered over the internet !

How tight (turns past fingertight) are you making it now ?

Graphite is very soft and if you "force the nut with more strength" there is a chance that it will squeeze into the narrow channels that take air to the flame.

Peter

Well, I have not tightened it at all seeing that it didn't fit as well as the original ferrule. SO, I have not tried tightening it really. I am currently using the one that was in the system.