Vacuum Pipe Sizing

Doesn't the vacuum pump sales rep have a chart? I bought 3-25 hp rotary screw vacuum pumps and the installation book we got had a chart based on CFM and vacuum loss per distance.

Any book on vacuum technology has the data.

To know the HP is not sufficient, you need the pressure too.

Tube sizing is very different according to physics of flow: viscous, Knudsen, molecular?

RHABE

As others have said, you have to know the flow rate, fluid, and pressure. Vac pump HP is not the right starting point. ONce you know the above, compressible pressure drop calculations from 10 Torr and higher conform to classical calculations. You probably can use traditional calculations down to 3 Torr without significant error. Given such a high HP pump, I doubt you're working below those pressures. Best wishes.

Thanks to the feedback. Further to that , I have the data corresponding to the flow and vacuum pressure. Each 50HP pump is around 730 cfm with operating vacuum pressure of 28" Hg. However, I know what vacuum pipe size is proportional to the flow and vacuum pressure. What i mean is the chart that shows equivalent pipe size corresponding to the flow and pressure loss.

Google "vacuum pipe sizing", you should get 235,000 threads to check out.

Dear Friend,

Your message is not containing the data like, quantity to be handled, vaccuum, density of the medium to be handled etc.

It is very simple. first decide the quantity and vaccuum, to be obtained. There are standards for the velocity for different materials, an it may vary from 3.0 Metres/Sec. to 30 Metres/sec.

Then you can size the piping and calculate power required.

Thanks,

DHAYANANDHAN.S