Gasket Discussion, Comparison PTFE vs Viton vs Polysteel vs Solid PTFE or Envelope ?

[Old Gold]

Tuf-Steel is probably the best bet, no? I don't know how legitimately difficult it is to create a seal with, but it should be great for the application.
I think that being able to leave a gasket on, sanitize the interior of a system with solvents (say, nonpolar flush, then isopropyl or ethanol or acetone flush), and set up for another run with minimal gasket and clamp removal is ideal. Create your seal, and don't keep removing it.

We need to upgrade our material loading mechanisms. If we could avoid removing clamps in that process, we could eliminate the need to EVER remove a clamp once it is sealed on gasket. For this, I say something like Tuf-Steel.

 

[Symbiotic AD]

Tuf-Steel is probably the best bet, no? I don't know how legitimately difficult it is to create a seal with, but it should be great for the application.
I think that being able to leave a gasket on, sanitize the interior of a system with solvents (say, nonpolar flush, then isopropyl or ethanol or acetone flush), and set up for another run with minimal gasket and clamp removal is ideal. Create your seal, and don't keep removing it.

We need to upgrade our material loading mechanisms. If we could avoid removing clamps in that process, we could eliminate the need to EVER remove a clamp once it is sealed on gasket. For this, I say something like Tuf-Steel.

Interesting. I like this idea, but I don't know how we could load a column without breaking the seal.

 

[Old Gold]

Interesting. I like this idea, but I don't know how we could load a column without breaking the seal.

I dunno. Could ground material absolutely not possibly be fedd and dispersed through, say 1 inch lines?
It's either that, or a sliding mechanism that creates a column opening, and when slid back into place, fits within a gasket of sorts. I haven't even tried to legitimize it.

 

[HashoftheTitans]

I think this is more trouble than it's worth. You might as well get a second column. It takes me less than five minutes to switch columns and pull a vac. I doubt feeding material or flushing it with a second solvent would be anywhere in the same ballpark in terms of efficiency.

 

[Old Gold]

I'm not worried about time. I'm talking about practicality of creating a seal over and over with something like Tuf-Steel.

What kind of gaskets are you using, sir?

As for flushing solvents, how do you think commercial scale productions clean things? They go into the manhole with acetone and paper towels?? Lol nooo. And where do you think all these "showerhead" pieces came from. They're used for sanitary application cleaning.

 

[Symbiotic AD]

I'm not worried about time. I'm talking about practicality of creating a seal over and over with something like Tuf-Steel.

What kind of gaskets are you using, sir?

As for flushing solvents, how do you think commercial scale productions clean things? They go into the manhoke with acetone and paper towels?? Lol nooo. And where do you think all these "showerhead" pieces came from. They're used for sanitary application cleaning.

The other upside to a feed tube would be saving $ on replacement seals, but a downside that I see would be introducing atmosphere into the vessels. You'd have to use nitrogen or another inert gas, I almost don't think its possible without causing another issue.

I use EDPM triclamp sanitary gaskets right now, but I want to go colder than -40c.

Also.. I wish I could just run acetone through my system to clean it... that would be amazing. It's too bad I'm overly concerned about contamination and I let my parts air dry after cleaning for way longer than necessary.

 

[ple1ades]

We use Gylon in our lab AZ state lisenced facility.
http://www.garlock.com/en/products/gylon

 

[HashoftheTitans]

I'm not worried about time. I'm talking about practicality of creating a seal over and over with something like Tuf-Steel.

What kind of gaskets are you using, sir?

As for flushing solvents, how do you think commercial scale productions clean things? They go into the manhole with acetone and paper towels?? Lol nooo. And where do you think all these "showerhead" pieces came from. They're used for sanitary application cleaning.

I use PTFE

I understand that industrial applications may do secondary solvent flushing, but they also do large enough runs to have downtime for cleaning. Using a 4" column, and flushing after every run would nearly slow production to a halt.

In my opinion, if you are running enough of the same material, you can run 3-6 columns in a day and only clean the entire system at the end of the day. I agree that semi-permanent seals would be ideal, and I think they could be used everywhere in the system except the ends of the column. That way if you want to flush the system, you could just throw on an empty column and flush it.

 

[Old Gold]

I like PTFE too. Maybe I also like it in the butt ([I'm anal] but I clean my system entirely between every run. My acetone wipe downs attest to the need for that on the inside of my column, as well as my collection pot. Residual amounts add up. And given the "spout" technology possible, some people don't ever have to take a clamp off of the collection pot.


Don't get me wrong, I aint trying to be lazier than shit on bricks, but it'd be cool to avoid the torquing of nuts/bolts on triclamps hourly.

 

[HashoftheTitans]

I totally agree, but I just don't see that being an option given the current design of CLSs. Personally, before I would be concerned with cleaning my system between column switches, I would be more concerned about contaminants in the solvent and source material than in the process of switching columns if done properly.

 

[BigJohnny]

Tried to attach the pic of the gasket

Holy shit man, that gasket has been horribly misaligned..... multiple times. I hope you're not still using that, because it was garbage the first time that inner ring got crushed.

I'm currently using PTFE, Torque to 20 Ft Lbs, and always seem to get a good seal, even with the 10" gaskets.

 

[Symbiotic AD]

I like PTFE too. Maybe I also like it in the butt ([I'm anal] but I clean my system entirely between every run. My acetone wipe downs attest to the need for that on the inside of my column, as well as my collection pot. Residual amounts add up. And given the "spout" technology possible, some people don't ever have to take a clamp off of the collection pot.


Don't get me wrong, I aint trying to be lazier than shit on bricks, but it'd be cool to avoid the torquing of nuts/bolts on triclamps hourly.

Always clean your system before runs! Cross contamination is very a real thing, and residual contamination is also very real.

 

[Old Gold]

The other upside to a feed tube would be saving $ on replacement seals, but a downside that I see would be introducing atmosphere into the vessels. You'd have to use nitrogen or another inert gas, I almost don't think its possible without causing another issue.

I use EDPM triclamp sanitary gaskets right now, but I want to go colder than -40c.

Also.. I wish I could just run acetone through my system to clean it... that would be amazing. It's too bad I'm overly concerned about contamination and I let my parts air dry after cleaning for way longer than necessary.

Dunno why this just hit me, but EDPM is not well-suited for saturated hydrocarbons like butane....
It is supposed to take acetone well though? Wtf? It's a rubber elastomer, no?

 

[SSpartsgeek]

Tuf-Steel Gaskets

Tuf-Steel Gaskets

Just to let you guys know, Glacier Tanks is carrying Tuff Steel gaskets , PTFE impregnated with SS316 , designed for cryogenics and temp rated down to -315. They guarantee 500 cleaning cycles but not sure exactly how that translates to this application. They are not on the website yet but the rep emailed me and said you can place an order by sending an inquiry through info@glaciertanks.com . They are available in sizes from 1"-12"

http://www.rubberfab.com/sites/default/files/products/pdfs/TufSteel_5.pdf