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Ajcoholic
07-01-2014, 06:17 PM
So, my Elmo Rietschle (approx 10 HP) regen blower is in transit.

I plan to get it plumbed up asap after it arrives. The electrician is coming to hook it up (as well as some other work) but I will be hooking the vacuum to the Buddy of course.

I am thinking the inlet will be about 2 1/2" based on other similar sized pumps. My plan is to break my 48" by 48" table into two 24" by 48" zones - using a 1.5" x 3" aluminum tube attached under the table and having a hole that will be centered in the middle of each zone (left and right of the powerstick).

If I have a 2 1/2" pipe coming off the pump, split into a Y with a valve on each branch going to the aluminum tube... would a 2" line be big enough to go to each zone of the table? The reason I ask is that 2" and under piping and valves are easy to get here, larger I will have to order in. Not an issue, but if 2" will do then I will try that first.

I can get spiral reinforces vacuum hose locally so that's no issue - since the Buddy obviously needs a flexible hook up.

If I have to go to a 2 1/2" valve - does it make any difference if you use the white PVC piping or the black ABS stuff? Both I'd have to order.

Thanks,
Andrew

Brady Watson
07-01-2014, 06:43 PM
2" stuff should be fine since your bottleneck will be at the 1x3" tubing anyway. I like the PVC schedule 40 stuff in this neck of the woods. I don't recall if ABS is pressure rated (It should say it - otherwise assume it is for drain & waste). There is a minor implosion hazard on high Hg" pumps, but I have never witnessed this personally.

Be sure to add an extra valve to the mix that can be opened to atmosphere. Most of the better pump manufacturers recommend that you don't turn the pump off & on more than 3x in a 1 hr period because it is hard on the motor windings. Instead, open the valve to atmosphere (make sure this gets filtered before the pump & watch small animals & kids!) and turn off your working zones. Swap material with pump running & then open working zones & close purge valve to seal it off - then run your parts & repeat.

FYI - the starter that comes with your pump should have an adjustment for amperage. Do not be surprised if the pump turns off during the first hour or so...just increase amperage a little (so you still have protection) and run it again, until you get the right setting.

-B

Burkhardt
07-01-2014, 08:55 PM
.......I don't recall if ABS is pressure rated (It should say it - otherwise assume it is for drain & waste). There is a minor implosion hazard on high Hg" pumps, but I have never witnessed this personally.......

No problem with ABS at all. I am using 4" foam core drainage ABS pipe for high vacuum up to 27" as reservoir and according to spec, this should be good up to temperatures of 140 degrees F.

A 2" pipe would even be much less a problem.

Ajcoholic
07-01-2014, 10:40 PM
No problem with ABS at all. I am using 4" foam core drainage ABS pipe for high vacuum up to 27" as reservoir and according to spec, this should be good up to temperatures of 140 degrees F.

A 2" pipe would even be much less a problem.

Well the Regen blower is only up to about 5 PSI vacuum (120 " water I think or about 8 to 9" Hg) so ABS would be OK.

The aluminum channel I ordered is 1.5" by 3" - 4.5 square inches cross section - VS the 4.9" area of the 2.5" diam pipe.

I figured Y ing off from the 2.5 to 2" (which is approx 3.15 sq in area) would still give me more combined area from the 2.5" --> two 2" --> two aluminum tube. Only when just one side was selected would I have a little reduction in cross sectional area.

If I can order 2.5" valves I probably will. Ill talk to my plumbing guy this week and see. If this takes another week or two I guess its no biggie.