Pumps and Air Requirements | Equipment Q&A | Spray Foam Technical Questions and Answers | SprayFoam Magazine Q&A Forums

Q&A Forums

Author	Comments
Arthur Gillis Posted: Mar 15, 2007 10:09 AM	Pumps and Air Requirements From what I understand one of two types of pumps are typically used to feed proportioners, either a diaphragm (husky 1040) or piston 2:1. Do both pumps perform equally with ½ lb and 2 lb foam?? What are the benefits of each type? Also, what are the air requirements of each? I know it depends on how much material your trying to move, assuming I am running a H20/35 full tilt how much air would I need for each and material at around 65degrees. Also, how much air does an air purge fusion gun need when running a H20/35 full tilt? Does it matter if you are running ½ lb or 2 lb foam?
Posted: Mar 15, 2007 08:26 PM	Sounds like you are asking indirectly how big (or small) of an air compressor you can get away with. The gun air depends on the mix chamber you use and the pressure. Look in the gun manual for the chart. Each stick pump uses very little, I'd estimate 2 cfm each or so. All said with just the pumps and gun approx 3hp is smallest but usually 5hp is the smallest standard size you will find. Anyone else?
Gerry Wagoner Posted: Mar 15, 2007 08:59 PM	7.5 hp.
Gerry Wagoner Posted: Mar 15, 2007 08:59 PM
Posted: Mar 15, 2007 09:36 PM	This is a compressor that is going to run all day for years. You have to get a high quality machine. If you skimp and buy something cheap it is going to cost you big in terms of downtime in the middle of a job. If nothing else, check out www.eatoncompressor.com for a little lesson on compressor basics. In short the "budget" compressors just won't cut it. Bigger is better it will run less, stay cooler, and last longer. I had a not so cheap 80 gallon/7hp compressor from Home Depot while I waited for my compressor from Eaton to come and I broke 2 of them in less than 3 months. It cost me big time the first time it broke in the middle of a job. Tim Granite State Spray Foam Co.
Arthur Gillis Posted: Mar 15, 2007 10:03 PM	How about the pumps. Do either work for 1/2 lb oc and 2 lb cc.
Posted: Mar 23, 2007 06:54 PM	I had problems as a result of the diaphram pumps. I'm pretty sure the diaphram pump froths the B-side with the new roof foam. I switched to the 2:1 sticks on both and have not had any problems since. Erik
Michael Flander Posted: Apr 02, 2007 02:36 PM	Most pumps require right around 3 cfm under normal running condition. The gun itself will use 3-5 cfm, and should be ran at 80 psi, no more, no less. Diaphragm pumps will work for the iso side on almost all foam materials out their. The difference is in the resin side. Because of the blowing agent used in the resin of 2lb foams, diaphragm pumps may cause frothing due to the length and strength of suction. This can cause cavitation in the pumps. You are much safer using a stick pump on the resin side of closed cell foam because of this. Stick pumps are available anywhere from 1:1 to 5:1 air to fluid ratio. This means if you have a 2:1 stick pump with 100 psi of air going to it, the fluid pressure will be around 200 psi minus whatever pressure loss occurs between the pump and the proportioner. Generally I find you will have around 10 psi pressure loss. All diaphragm pumps that you would use are 1:1. Check with your proportioner to find what the inlet fluid pressure should be and size the stick pump to match. The 20/35 needs a minimum of 60 psi, and max's at 25% of the outlet fluid pressure. If you run outside these specs, the check balls in the pumps may not work properly. Lastly, I agree with the others, you should buy a high quality air compressor that will last. We recommend running a piston compressor between 70-80% of its capacity, this helps to ensure longevity. Piston compressors are NOT designed to run at full capacity for great lengths of time, and will shorten their running life tremendously. Screw compressors on the other hand, run very well at full bore. Thanks, Mike Flander - Endisys mikeflander@endisys.com
Bubba Pallo Posted: Jun 06, 2007 11:57 PM	The H-20/35 is actually the model# for three different units. You actually have an H-20, H-25 OR an H-35. I'll use the H-20 here, because it has the highest flow rate, and your question was full tilt. With an 04 mix chamber and 1500 psi this machine will produce about 38 lbs/min of foam. That's right about 3.9 gpm using 9.75 #'s/gallon. The 1:1 transfer pump and the diaphragm pump will both consume about 1.5 cfm/gallon X 2 transfer pumps = 11.7 cfm. divide this by .85 to account for inefficiencies and your filthy air filters and you have roughly 13.75 cfm required for your H-20/35 (H-20) full tilt boogie. Double this figure if you're running 2:1 pumps as they require twice the air volume to deliver the same fluid volume as the 1:1/diaphragm pump. No need to worry about purge air on this one, you'd be right about 7 cfm at 100 psi. You may want to consider breaking out your equipment manuals and reading them. Try to understand how to interpret the performance charts and flow/pressure graphs etc. All you need to know is in those books and in your noodle. You can find them all on line too at the manufacturers' websites. The more you know about your equipment, how to size it and how to properly maintain it the more money you will make in the long run. Sorry to preach, I'm a schmuck! Hope this helps.
Michael Flander Posted: Jun 07, 2007 04:42 PM	Purge air CFM only comes into account in a trigger off situation, so when purge air comes into play, the transfer pumps do not require any more air, thus lowering the actual needed CFM. It depends on the stick pump, but most 2:1 stick pump air motors do not have any more surface area then a diagphram pump, so for the most part, CFM needed is close, not double. For example, a 2:1 ipm requires a little less then 2 cfm per gallon pumped, vs. the 1.5 called for on a 1:1. Mike
Bubba Pallo Posted: Jun 15, 2007 12:11 AM	Mike, Correct, purge air only in trigger off position. Purge air was negligible in my example as stated. Correct again, 2:1 stick pumps air motors have roughly the same area as a diaphragm pump and a 1:1 stick pump for that matter, however, the pump lower is roughly 1/2 the size requiring 2 X's as many strokes to displace the same volume of fluid, thus twice the required cfm to the air motor. Saavy? Graco 1:1 = 1.5 cfm/gal, Graco 2:1 = 3.0 cfm/gal exactly twice the required cfm/gal due to the fact that they use the same size air motor, yet the 2:1's lower is 1/2 the size. Bubba
Michael Flander Posted: Jun 15, 2007 10:36 AM	Graco Fast Flo 1:1 = Roughly 1.5 cfm per gallon - Graco manual 307427 p. 38. IPM OP232C 2:1 or Graco T2 2:1 = roughly 2 CFM per gallon. IPM manual OP232-INST p. 4, and the graco t2 is pretty much the same pump. The Graco Standard 2:1's are now discontinued, and the IPM's were much more widely used because of the lack of a usable bung adapter on the Graco Standards. I have a lot of customers out there running off of this information, so I just wanted to clarify. The 20/35 three machine issue... I ran into the fourth the other day :). Apparently for awhile they made the 35PRO with 104 pumps and a max pressure of 2800. Mike Flander

Author

Comments

Arthur Gillis

Posted: Mar 15, 2007 10:09 AM

Pumps and Air Requirements

From what I understand one of two types of pumps are typically used to feed proportioners, either a diaphragm (husky 1040) or piston 2:1. Do both pumps perform equally with ½ lb and 2 lb foam?? What are the benefits of each type? Also, what are the air requirements of each? I know it depends on how much material your trying to move, assuming I am running a H20/35 full tilt how much air would I need for each and material at around 65degrees.

Also, how much air does an air purge fusion gun need when running a H20/35 full tilt? Does it matter if you are running ½ lb or 2 lb foam?

Posted: Mar 15, 2007 08:26 PM

Sounds like you are asking indirectly how big (or small) of an air compressor you can get away with.

The gun air depends on the mix chamber you use and the pressure. Look in the gun manual for the chart. Each stick pump uses very little, I'd estimate 2 cfm each or so.

All said with just the pumps and gun approx 3hp is smallest but usually 5hp is the smallest standard size you will find.

Anyone else?

Gerry Wagoner

Posted: Mar 15, 2007 08:59 PM

7.5 hp.

Gerry Wagoner

Posted: Mar 15, 2007 08:59 PM

Posted: Mar 15, 2007 09:36 PM

This is a compressor that is going to run all day for years. You have to get a high quality machine. If you skimp and buy something cheap it is going to cost you big in terms of downtime in the middle of a job. If nothing else, check out www.eatoncompressor.com for a little lesson on compressor basics. In short the "budget" compressors just won't cut it. Bigger is better it will run less, stay cooler, and last longer.

I had a not so cheap 80 gallon/7hp compressor from Home Depot while I waited for my compressor from Eaton to come and I broke 2 of them in less than 3 months. It cost me big time the first time it broke in the middle of a job.

Tim
Granite State Spray Foam Co.

Arthur Gillis

Posted: Mar 15, 2007 10:03 PM

How about the pumps. Do either work for 1/2 lb oc and 2 lb cc.

Posted: Mar 23, 2007 06:54 PM

I had problems as a result of the diaphram pumps. I'm pretty sure the diaphram pump froths the B-side with the new roof foam. I switched to the 2:1 sticks on both and have not had any problems since.
Erik

Michael Flander

Posted: Apr 02, 2007 02:36 PM

Most pumps require right around 3 cfm under normal running condition. The gun itself will use 3-5 cfm, and should be ran at 80 psi, no more, no less.

Diaphragm pumps will work for the iso side on almost all foam materials out their. The difference is in the resin side. Because of the blowing agent used in the resin of 2lb foams, diaphragm pumps may cause frothing due to the length and strength of suction. This can cause cavitation in the pumps. You are much safer using a stick pump on the resin side of closed cell foam because of this.

Stick pumps are available anywhere from 1:1 to 5:1 air to fluid ratio. This means if you have a 2:1 stick pump with 100 psi of air going to it, the fluid pressure will be around 200 psi minus whatever pressure loss occurs between the pump and the proportioner. Generally I find you will have around 10 psi pressure loss. All diaphragm pumps that you would use are 1:1.

Check with your proportioner to find what the inlet fluid pressure should be and size the stick pump to match. The 20/35 needs a minimum of 60 psi, and max's at 25% of the outlet fluid pressure. If you run outside these specs, the check balls in the pumps may not work properly.

Lastly, I agree with the others, you should buy a high quality air compressor that will last. We recommend running a piston compressor between 70-80% of its capacity, this helps to ensure longevity. Piston compressors are NOT designed to run at full capacity for great lengths of time, and will shorten their running life tremendously. Screw compressors on the other hand, run very well at full bore.

Thanks,
Mike Flander - Endisys
mikeflander@endisys.com

Bubba Pallo

Posted: Jun 06, 2007 11:57 PM

The H-20/35 is actually the model# for three different units. You actually have an H-20, H-25 OR an H-35. I'll use the H-20 here, because it has the highest flow rate, and your question was full tilt. With an 04 mix chamber and 1500 psi this machine will produce about 38 lbs/min of foam. That's right about 3.9 gpm using 9.75 #'s/gallon. The 1:1 transfer pump and the diaphragm pump will both consume about 1.5 cfm/gallon X 2 transfer pumps = 11.7 cfm. divide this by .85 to account for inefficiencies and your filthy air filters and you have roughly 13.75 cfm required for your H-20/35 (H-20) full tilt boogie. Double this figure if you're running 2:1 pumps as they require twice the air volume to deliver the same fluid volume as the 1:1/diaphragm pump. No need to worry about purge air on this one, you'd be right about 7 cfm at 100 psi. You may want to consider breaking out your equipment manuals and reading them. Try to understand how to interpret the performance charts and flow/pressure graphs etc. All you need to know is in those books and in your noodle. You can find them all on line too at the manufacturers' websites. The more you know about your equipment, how to size it and how to properly maintain it the more money you will make in the long run. Sorry to preach, I'm a schmuck! Hope this helps.

Michael Flander

Posted: Jun 07, 2007 04:42 PM

Purge air CFM only comes into account in a trigger off situation, so when purge air comes into play, the transfer pumps do not require any more air, thus lowering the actual needed CFM.

It depends on the stick pump, but most 2:1 stick pump air motors do not have any more surface area then a diagphram pump, so for the most part, CFM needed is close, not double.

For example, a 2:1 ipm requires a little less then 2 cfm per gallon pumped, vs. the 1.5 called for on a 1:1.

Mike

Bubba Pallo

Posted: Jun 15, 2007 12:11 AM

Mike,
Correct, purge air only in trigger off position. Purge air was negligible in my example as stated.

Correct again, 2:1 stick pumps air motors have roughly the same area as a diaphragm pump and a 1:1 stick pump for that matter, however, the pump lower is roughly 1/2 the size requiring 2 X's as many strokes to displace the same volume of fluid, thus twice the required cfm to the air motor. Saavy?

Graco 1:1 = 1.5 cfm/gal, Graco 2:1 = 3.0 cfm/gal
exactly twice the required cfm/gal due to the fact that they use the same size air motor, yet the 2:1's lower is 1/2 the size.

Bubba

Michael Flander

Posted: Jun 15, 2007 10:36 AM

Graco Fast Flo 1:1 = Roughly 1.5 cfm per gallon - Graco manual 307427 p. 38.

IPM OP232C 2:1 or Graco T2 2:1 = roughly 2 CFM per gallon. IPM manual OP232-INST p. 4, and the graco t2 is pretty much the same pump.

The Graco Standard 2:1's are now discontinued, and the IPM's were much more widely used because of the lack of a usable bung adapter on the Graco Standards.

I have a lot of customers out there running off of this information, so I just wanted to clarify.

The 20/35 three machine issue... I ran into the fourth the other day :). Apparently for awhile they made the 35PRO with 104 pumps and a max pressure of 2800.

Mike Flander

You need to login to reply to this topic. Please click here to login.