I went to music school with the son of the man who invented teflon coating for cookware.
he owns swanhill chemicals (well he did)
there is a polymer to get that to bond it is not pure ptfe and if they had any morals
they would tell you the polymer they bond it with.
ptfe can only be sintered and not melted.
otherwise its glued on.
what is the glue if it is not milled.
I could have misquoted but could be a lie as well.
Ill rephrase as new models reportedly have done away with thin coating that has flake off tendencies.
This market is so full.of scammers. If only i could bring myself to lie i would be retired by now.
But there you go. You’ve heard…
The reality is they told everyone they were chem duty and lied about quality, sources, supply chains changing and tollerances going down for cheaper production.
A company that does that is just a share holders company with commission based salesmen that will just sell pumps. They don’t really care about the customer. Don’t get me wrong Welch makes some good stuff. But myself I refrain from pushing anything but vacuubrand becusee thier diaphragm pumps are light years ahead of Welch.
When did the Welch pumps start to suck? (Pun intended) I’ve got a line on a couple old used 1402 that look pretty damn old
Sometime after they sold out. I think it was around the time I got in business.
When was that 2009?
Anyone ever used a Chemstar Dry? https://www.welchvacuum.com/en-us/rotary-vane-pumps/rotary-vane-pump-chemstar-dry-2070
Its like a dual rotary vane diaphragm, pulls up to 300 L/min!!
did you get a price out of them?
Mucho $
Cascade is advertising it for slightly under $14,000 so you can probably find a used one (if you can find a used one) for about half that.
Having worked on cars its better to drain it quickly and flush a little clean fluid through. The speed of the oil coming out will bring more heavy contaminants out
Check out the alcatel 602Ps. Not technically for chemical service but they’re for sputtering applications that deal with much more aggressive process gas than organic solvents. They run a bearing purge with N2 constantly. Since Alcatel went under they can be found for around $4k used and run like 300+ scfm with an ultimate vacuum of ~50 mtorr. We run an LM without the purge and it has no issues and we run some real nasty shit
Hello again this pump stared sonud difrent need a little help on how to change oil on this one the manual is just advertising not much help
I don’t think those pumps have oil. I think you need a diaphragm rebuild kit if anything.
it helps to post a picture of the sticker to indicate the make and model.
Looks like a Welch 205x…
Heres a link to the quick start manual found from a google
Quick-Start-and-Maintenance-CB2052.pdf (276.3 KB)
You can buy a rebuild kit here. There is no oil.
https://cascadesciences.com/shop/ovens/vacuum-oven/vacuum/vacuum-pumps/welch-cs2052-diaphragm-pump/
These are cheaper. Idk if they are the same?
Yup, just verify you get the rebuild kit for the right pump model.
This is just straight up bullshit.
I have a Welch 2052 open at home right now I’ll send pics. All the solid parts are blocks of PTFE. It’s very obviously NOT just a coating.
These pumps are the shit, they sell themselves and can be rebuilt a million times and work just like new. Fantastic engineering from a fantastic company.
Just for reference, Welch is manufactured by GardnerDenver (a publicly traded huge ass company). They’re great.
