Too much CFM during short path

Hash and Stuff Distillation
1

Hello Everyone,

I recently got a Lab Society 5L full bore set up. I have a Welch 8CFM, and a BVV 21.5 CFM. Is it anyone’s opinion that using the BVV 21.5 CFM pump would be too much for a 5 L shortpath? Just curious if anyone has had any bad experiences using a pump with too much CFM on a smaller shortpath? I was planning on using the welch as a roughing pump and the BVV for my main body. Let me know your opinions please and thanks!

Best regards,

2

No you should have at least 4cfm per liter of your flask. Ive ran dual e30s on a 5 and dual alcatels on a 2l. Yojll be fine, get a roughing pump and use the biggest cfm pump you can

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3

Perfect. That’s what I figured, but I thought I would ask anyway.
Thanks again!

4

That duo seal will get soaked quick, id get a different roughing pump or use the other 8cfm one. I use a sogevac and its the best roughing pump ive ever used, and have really good and cold cold traps.

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Sorry for the confusion. They are rotary vane pumps. I have the Welch CRVpro 8 and the BVV 21.5 CFM. I was thinking I may run with the Welch 8 CFM as the roughing and the BVV as the main.

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Ya that would be my suggestion if you dont want to get another roughing pump. The crv will work just fine, and be easy to flush every few runs

7

A single e30 on my 5L rips through vac. Can pull sub 100 on first pass and sub 50 on 2nd

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8

I’m also using a e30 on my 5l and it’s ripping down sub 100 micron 1st pass as well

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I was using a AI 21 cfm vac pump on a Lab Society Full bore and pulling down really deep. My buddy who’s a consultant was there and he was shocked how low we were pulling main fractions. Definitely use the 21 cfm

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