How much  vacume pressure required for lifting water up to 50 ft height ?

If a 3*3*3 ft volume of closed vessel kept at 50 ft height connect to 75mm dia pipe for lifting water up to 50 ft height how much vacume pressure required ?

3 Answers

  • Anonymous
    1 month ago

    Rest are correct. But, Vacuum is Not "pressure" . It is rated in inches, microns, Torr, or Millibars. Not PSI or NSM. No more than 30" of Mercury is ever possible. This is equivalent to about 33 feet of water, as Hg is 10x the density of water.

    It would have to be forced from bottom. It can then be be forced, theoretically, to any height.

  • 1 month ago

    Water cannot be lifted by a vacuum higher than 34 Feet. It can be pressure pumped several thousand feet at .433 Psi per foot.

    pumping water up 50 feet requires pressure of 21.65 or more psi.

  • 1 month ago

    It is a trick question kid. Vacuum does not PULL water. It is air pressure on the other side that PUSHES the water up the column. Air pressure is equal to around 34 feet of water height. So even if you generated a pure vacuum, the water column would only go 34 feet up the pipe. From a historical standpoint, that is one reason the Virginia City Comstock load mines shut down. They could not get the water out. A gentleman named Sutro (look up Sutro Tunnel) dug a tunnel out the side trying to fix the problem but it came too late. This is why when you put in a deep well the pump goes at the BOTTOM of the well. With positive pressure at the bottom of the water column you can pump water up a very long pipe to the top because you can generate as much pressure as you need to do it. But if you try to put a vacuum pump at the top, the water will only come up 34 feet.

    • Cap'n. America
      Lv 4
      1 month agoReport

      Excellent, But, don't call posters: "kids". May be an ignorant farmer's housewife that is recently widowed and needs to save engineering fees to solve an irrigation problem.

Still have questions? Get your answers by asking now.