Sciencemadness Discussion Board

Salvageable? Usable?

electrokinetic - 20-5-2020 at 12:04

I just saw the crack at the neck of this distillation column. It seems hairline only, in the sense that all both the inside and outside of the neck are smooth and there are no chips missing.

Can it be salvaged or repaired? Is it still safe to use?

thanks

IMG_1339.JPG - 2MB IMG_1340.JPG - 1.9MB

DraconicAcid - 20-5-2020 at 12:06

I personally wouldn't use it for a distillation, but it should be fine for refluxing.

j_sum1 - 20-5-2020 at 15:01

I had a Liebig with the exact same injury recently. I used it for non-critical distillations for several weeks until it finally succumbed.
So, not high temp, nothing volatile and toxic like bromine, and no vacuum distillations.
It seemed to be fine for that.

Texium - 20-5-2020 at 16:32

I second what DA says. It should still be perfectly fine as a reflux condenser (and still would be even if that top joint was more badly broken than it is). Just don’t use it for distillations.

SWIM - 20-5-2020 at 18:21

Don't know how much effort you'd want to put into this, but if you cut the end off just past the crack and sand it a bit you won't have to worry about that crack running eventually.

Straight cracks like that can slowly grow longer with repeated heating and cooling even if it never gets all that hot.

Of course then you'll only be able to use stoppers in the end, but it should last that way.

Is that a 19/22?

Hey! That's not a distillation column, its a coil and tube condenser!

Those things are pretty efficient and not cheap.

It is 19/22 isn't it?

A common size for that uncommon kind of condenser.





[Edited on 21-5-2020 by SWIM]

electrokinetic - 21-5-2020 at 13:05

Quote: Originally posted by DraconicAcid  
I personally wouldn't use it for a distillation, but it should be fine for refluxing.


Thank you.

electrokinetic - 21-5-2020 at 13:07

Quote: Originally posted by j_sum1  
I had a Liebig with the exact same injury recently. I used it for non-critical distillations for several weeks until it finally succumbed.
So, not high temp, nothing volatile and toxic like bromine, and no vacuum distillations.
It seemed to be fine for that.


Thanks.

electrokinetic - 25-5-2020 at 18:35

Quote: Originally posted by Texium (zts16)  
I second what DA says. It should still be perfectly fine as a reflux condenser (and still would be even if that top joint was more badly broken than it is). Just don’t use it for distillations.


Thanks!

draculic acid69 - 25-5-2020 at 19:41

U can use something called a triangle file to score the glass below the crack I've done it using a smaller file on thinner tube

draculic acid69 - 25-5-2020 at 19:44

Or u could use a blowtorch to seal the crack.it might warp the GG joint but it won't crack further.

Ubya - 25-5-2020 at 22:46

Quote: Originally posted by draculic acid69  
Or u could use a blowtorch to seal the crack.it might warp the GG joint but it won't crack further.

i tried fixing a flask like this, i sealed the crack but now there wre bubbles inside the glass, he is better of cutting away the cracked part

Belowzero - 25-5-2020 at 23:00

Quote: Originally posted by draculic acid69  
Or u could use a blowtorch to seal the crack.it might warp the GG joint but it won't crack further.



I once contacted a technical glass workshop if they could repair one of my coils that has a similar problem, they told me it needs to be reheated/baked to remove the stress from the glass, apparantly this creates internal stress which can result in further cracking upon heating.

[Edited on 26-5-2020 by Belowzero]

draculic acid69 - 25-5-2020 at 23:42

Quote: Originally posted by Belowzero  
Quote: Originally posted by draculic acid69  
Or u could use a blowtorch to seal the crack.it might warp the GG joint but it won't crack further.


I once contacted a technical glass workshop if they could repair one of my coils that has a similar problem, they told me it needs to be reheated/baked to remove the stress from the glass, apparantly this creates internal stress which can result in further cracking upon heating.


[Edited on 26-5-2020 by Belowzero]


I've melted cracks shut that didn't crack after not annealing

Belowzero - 25-5-2020 at 23:44

Good to know, might give it a shot, I have a few parts that have cracks in it.

XeonTheMGPony - 26-5-2020 at 03:33

Borosilicate is much friendlier for that kind of repair, but if you can happen to anneal it, it is all ways a good idea.

for a complicated glass wear like that I'd certainly preheat the whole thing then use a good propane torch that has a wide heat pattern.

Start from the base of the crack and heat the whole area up then slowly focus the heat on the spot til it starts to seal then work your way up keeping things as uniformly heated around the rest of it