Busch or liquid ring?

[CMM]

Right now I have one of those blue 3hp tuthill vacuum pumps but I want something that pulls more CFM. It pulls 25-26"Hg but drops a lot with a few small leaks. I can maintain 24-25" now, but want more. I have around 2000 taps, about 2000ft of 1.5" over 1.5" wet and dry and about 15- 1" mains that average 800-1000ft. If they both can get the same CFM and in.Hg, which is better, or is it just personal preference and price. I don't have the ability to run a water cooled pump at this time. Thanks.

[eagle lake sugar]

I found myself in the same situation this year. After adding 850 taps and tubing, my 35cfm liquid ring just won't handle it. I'm ordering a 73cfm Atlas Copco sealed vane pump this morning from M.E.S. $6264 including a vfd and moisture trap.

[DrTimPerkins]

If they both can get the same CFM and in.Hg, which is better, or is it just personal preference and price. I don't have the ability to run a water cooled pump at this time. Thanks.

We've used just about every type of pump there is in several different applications, from sap pullers to rotary claw pumps. We tend to change things a lot as different research needs dictate. We are now using almost exclusively Busch pumps. Before that we used oil-cooled liquid ring pumps (we may have a couple of these available for sale at the end of this season). At this point I don't think I'd ever get anything but another Busch pump. They are quiet, use very little oil, can achieve high vacuum and move a lot of CFM. Maintenance is fairly modest (but don't ignore it). About the only thing you want to be sure of is that you have a completely fool-proof moisture trap installation. If you pull sap through one of these there is a good chance you'll have to send it back for refurbishment. With a liquid-ring that isn't a problem.....you just change the oil and you're back in business. CDL carries a comparable type of rotary claw pump along with the Busch pump....we've not tried it yet though, so can't really comment on it.

[brookledge]

I have a Nash liquid ring with a vsd. I used to run 2 rotarty vain at about 18" at 220volts they drewover 15 amps each. With my new pump I have the transducer programed into the drive to maintain 27" and as long as I don't have leaks it runs at 1100 to 1200 rpm and only using around 15 amps. Full rpm it jumps up to 26 amps on 220.
Another benifit is knowing when you have a leak. All it takes is a tap to back out a little and you know it.
With the liquid ring if any sap gets into it you don't do any damage to the pump. If there is adraw back you need to have cool water to keep it running more efficiently. While it still operates ok the hotter it is the faster the motor runs . Mine is set up with a 5/16 line bringing in cool water
Keith