You are correct on maximum temperature without reprogramming, but that is more than adequate, with adequate vacuum, as evidenced by the undeniable fact that it works. I know of one lab supplying Clear, simply using a row of them.
You are sorely mistaken regarding maximum vacuum. With no rotary seals, vacuum levels are dictated by the pumps capabilities.
The Kugelrohr works for the C-10 thru C-21 fractions, leaving behind the higher boiling point ones.
If you will send me contact information at
[email protected], I will be glad to put you in direct contact with Pharmer Joe.
The Welch 1405 was available for free and did a good job for what we used it for. As it isn't in contact with the product, pollution isn't an issue.
Joe used the Welch Chem Dry on the equipment he built. Any issues with that?
We use Welch 2052 diaphragm pumps on our ovens. I also did early development work using GAST diaphragm pumps for solvent recovery, but they are limited on maximum vacuum and diaphragms fail, so moved on.
I gave up on water aspirator pumps after noting that they are both limited to about -28.5" Hg vacuum levels and they pollute the water stream. We have several plastic and metal ones lying around unused already.
They can be hooked up to a sump pump in a closed tank, to keep the pollution contained, but that adds equipment.
We use an air aspirator venturi pump on the Mk IVC/VC Terpenators, which will pull to -29.5" Hg vacuum, but is extremely noisy without mufflers and uses 22cfm of air to operate.