Manometer, U-Tube Pressure Calculator

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Hydraulic and Pneumatic Knowledge

Manometer Application Equation for Determining Pressure

Manometer calculators on this webpage:

  • U-Tube Manometer Measuring Pressure Calculator
  • U-Tube Manometer Differential Pressure Calculator
  • Single-Leg Manometer - Gauge Pressure Calculator
  • Inclined Single-Leg Manometer Measured Pressure Calculator
  • Inverted U-Tube Manometer Equation Calculator

Liquid-column manometers measure pressure by determining the vertical displacement of a liquid of known density in a known gravitational field. Typically they are constructed as a U-tube of transparent material (glass or plastic). The pressure to be measured is applied to one side of the U-tube. If the other (reference) side is evacuated (zero pressure), the manometer measures absolute pressure; if the reference side is open to the atmosphere, it measures gage pressure; if the reference side is connected to some other pressure, the manometer measures the differential between the two pressures. Manometers filled with water and different oils are often usedto measure low-range differential pressures. In some low-rangeinstruments, one tube of the manometer is inclined in order toenhance the readability. Mercury-filled manometers are used forhigher range differential and absolute pressure measurements. In the latter case, the reference side is evacuated, generally with a mechanical vacuum pump. Typical full-scale ranges for manometers vary from 10 in. of water to 3 atm..

To see the equation utilized in these calculators see:
Manometer Application Equation for Determining Pressure