PD Blowers in Series?

[KernOily]

Hi guys. Not sure this is the right forum, so please recommend an alternate if I need to move this post. I have two PD lobe blowers (Gardner-Denver GGB type, 15 hp each) that my client is proposing to put in series to meet a ~30 psig discharge pressure requirement. These are surplus equipment items they want to re-use, so purchasing new equipment is a non-starter.

The proposal is to use these blowers to replace an existing air compressor that cycles on and off to meet the load, which is 170 scfm.

I am certain I will need an intercooler and intercooler separator vessel. Also, I believe force feed lubrication is needed for pressures over 20 psig so I would have to figure that part out.

Beyond that, will this work, or should I run the other way?

Thanks in advance!

 

[georgeverghese]

The GD website doesnt take me straight to this GGB model, can you post a link to the specific page, and post us the mech / process datasheets also ?

 

[KernOily]

The GD website doesnt take me straight to this GGB model, can you post a link to the specific page, and post us the mech / process datasheets also ?

Thanks for your reply. Link: https://cemerynelson.com/product/duroflow-3004-positive-displacement-blower-vacuum-pump/

The exact model is GGBADBA.

Unfortunately, I do not have a datasheet. Wouldn't that be nice? The originals are long gone, so I would have to create new from scratch. I'll do that if I find some time.
Thanks!

 

[georgeverghese]

The corresponding model 3004 HR doesnt go beyond 105scfm at between 3500-4000rpm at 12.3hp or 85scfm at approx 3500rpm (see page 11 of Duroflow-17 brochure), so you're still short on throughput to get to 170scfm. And the other pamphlet says the horizontal version HR cannot be operated anymore than 1272rpm, so max possible flow will be even less.

 

[carlosbenjamin]

Hi guys. Not sure this is the right forum, so please recommend an alternate if I need to move this post. I have two PD lobe blowers (Gardner-Denver GGB type, 15 hp each) that my client is proposing to put in series to meet a ~30 psig discharge pressure requirement. These are surplus equipment items they want to re-use, so purchasing new equipment is a non-starter.

The proposal is to use these blowers to replace an existing air compressor that cycles on and off to meet the load, which is 170 scfm.

I am certain I will need an intercooler and intercooler separator vessel. Also, I believe force feed lubrication is needed for pressures over 20 psig so I would have to figure that part out.

Beyond that, will this work, or should I run the other way?

Thanks in advance!

Stacking PD blowers in series for 30 psig is tricky but doable with the right setup. You’re right about needing an intercooler and separator, otherwise, heat buildup will kill efficiency and the blowers. Force-feed lube is a must past 20 psig. Also, check the blower specs—some aren’t rated for that pressure. If the client insists on reusing these, make sure the first stage can handle the compression ratio without overheating. Might be worth running the numbers on a used compressor instead. Good luck!

 

[LittleInch]

Putting two PD machines in series is never going to work without constant VFD fiddling based on interstage pressure and sooner or later one will move a little bit more or less than the other and either get more pressure in between or less and rapidly lead to shut down.

You can feed a PD blower with a centrifugal compressor, but not two in series.

Also two identical machines won't move the same mass of gas when one is being fed with atmospheric pressure and the second at 15psi. Just wont work.