E olha só o que o cara fez ele colocou um aspirador de6.5 hp em cada furo, e abaixo um comentário que ele fez:
página horiginal
http://www.talkshopbot.com/forum/messages/27/5738.htmlDan, if you simply put 2 of these vacuum motors in series, then the second motor has to handle more compressed air (more dense) than the first, so they become mismatched and very inefficient. Two identical motors in series may only give you 10-20% more holding power.
In fact, the motor illustrated above already contains 2 turbines in series (that is why the can is so long). Some also have a 3-stage turbine. If you break open these motors, you should see that each stage has a different turbine, according to how the air is being progressively compressed.
Here is one of the index pages where you can see 1-stage, 2-stage and 3-stage examples.
BTW a perfect vacuum is about 1000 mbar, so 300 mbar is about 100" water.
Most shop vacs contain these very same Slovenian/Italian motors, and it is interesting to see the OEM specs at a site like
www.domel.si