Re: Need Help: Formula Needed
 

Wilson,
If I read your line of thinking right you are asking to move 2560 cu ft of air in one minute. I gather you are trying to exchange the air in the enclosed volume with some other gas. You are up against a wall here in that you will never move that volume through a 3/4" hose. You may be able to find blower assemblies that move that volume of air but not a single motor with a CFM rating. You are looking for a motor/blower assembly. The ratings of the assembly will include CFM at a specific static pressure (measured in inches of water). The static pressure relates to the air resistance of the ductwork. You will need to research that for a better understanding. In a catalog that we use frequently (Grainger), a radial blower rated for 3000 CFM at 0.0 in static pressure includes an integral 3 phase, 2 HP motor, weighs 132 lbs. and costs $660.
If you could be more specific we might be able to help a little more with your request.

Re: Need Help: Formula Needed
 

Thanks for your reply in helping in this matter; we have been busy to meet dead lines. Again I can't stress the amount of useful responses and help from the people from this site.

Al,
No, we are not trying to move volume of a container with other gases.
Yes, we are looking for a motor/blower assembly.
We have actually contacted Grainger and looked threw their catalogs and was unable to find the part needed. Being in the X-mas holiday it’s been even more difficult with companies closed till Jan 2nd. We have also contact several manufactures that would note they would help with the calculations, however it first starts with a laugh in all honest due to the ID dimensions we have been using and testing. Then it’s the serious and note they will get back with us with options. Being on this dead line the decision needs to be made promptly and can no longer wait on these manufactures.

Here is a list of companies we have contacted:
AWT, Electric Motors and Controls, Air Power Products Limited, AMATEC, CJ Machines Products, Danaher Motion, Pacific Scientific, Electric Trading Company, Graphic Parts International, Imperial Electric, Connect Company, Q Air California, Schmaltz Inc., Allied Electronics,

The names may be off just going by the list in my head and typing as I go, please forgive any mistakes.

-Wilson & Brandon

Re: Need Help: Formula Needed
 

The link below might be the type of pump your looking for.

http://www.pfeiffer-vacuum.de/shop/f...nav_status= j


If my calculations are correct, it will draw a vacuum to 1.450377e-010PSI or 14.50377 femto PSI. its lowest psi.
in ~35 seconds. I think this is almost a perfect vacuum (outer space vacuum)

hope this helps. :D

Re: Need Help: Formula Needed
 

Thanks for the help Scott, however that link dose not work. I went to their site and looked around a lot of them have the same figures (-10psi). If you could please provide a working link, as the link you sent didn't have an id number to do a search on the site. Thanks for the info and very intrigued on this product and if it is able to help us in this project.

Thanks again
-Wilson

Re: Need Help: Formula Needed
 

Wilson,
Can you restate your requirements now that you have done more research? How much air are you moving in what length of time? What are the dimensions of the inlet/exhaust? Sorry I didn't llok back at this earlier, I am on vacation.

Re: Need Help: Formula Needed
 

http://www.pfeiffer-vacuum.de/

go here,
1. click english flag, then click products, Turbopumps, online catalog
2. click generation of a vacuum, turbopumps
3. under "HiMag™ 2400, select the 3rd item down (PMP03492)
4. click tech specs on bottom of page.

all pressures are rated in millibars.
1e-9mBar = 1.45 x 10^-11 PSI (my last post was incorrect on the magnitude)

Hope this works better.

Re: Need Help: Formula Needed
 

If you check out the specification areas at the bottom of the screen, you will note that cooling water (100L/hr) is required as well as high voltage power supply 208/230 volt and it takes 6 minutes to run up. Also specs require the use of an ontool dry pump to achieve vacuum.
I bet this is in the thousands of dollars range.