This document discusses different types of manometers used to measure pressure. It describes U-tube manometers, which use mercury in two legs of equal area to measure liquid or gas pressure. Well-type manometers have one narrow tube leg and one wide reservoir leg, allowing small pressure changes to produce large changes in the tube height. Inclined tube manometers are slanted to improve sensitivity for small pressure differences. Micromanometers combine an inclined magnifying tube with a reservoir leg to precisely measure minute pressure changes.

2. Introduction
• Pressure measurement is one of the most
important measurement in continuous process
industries.
• Manometers measure the unknown pressure by
balancing against the gravitational force of
liquid heads.

3. Manometer
• Manometry refers to the measurement of
pressure by comparison to the hydraulic
pressure produced by a column of liquid.
• With the help of manometer, we can measure
comparatively high pressure and negative
pressure also.

4. Topic covered
• U tube manometer.
• Well type manometer.
• Barometer.
• Inclined tube manometer.
• Micromanometer.

5. U tube manometer
• Simplest manometer.
• Used in the measurement of
liquid or gas pressure.
• Both legs have same area.
• Manometric fluid of known
specific gravity is used.
• Mercury is generally used as
fluid.

6. Well type manometer
• One leg is a simple tube,
other leg is a large well.
• For small displacement of
liquid level in the well there
will be a large change in the
height of simple tube.

7. Barometer
• Principle of working: If one
end is at zero absolute
pressure then “h” indicates
the absolute pressure.
• Well type absolute pressure
gauge.
• Its range is from zero
absolute to atmospheric
pressure.
• High vacuum are not
measured.

8. Inclined tube manometer
• It is slant manometer.
• The angle of measuring
leg is about 10⁰.
• Inclination is done to
improve the sensitivity.
• This manometer is used
to measure very small
pressure difference.

9. Micromanometer
• One leg is well type and other
leg is inclined tube.
• Inclined leg consist magnifier.
• Initially both well and inclined
legs are at same pressure.
• Application of unknown
pressure causes meniscus to
move towards the reference
point.
• The difference between initial
& final reading gives change
in height.

10. Advantages and Disadvantages
of Manometer
Advantages Disadvantages
• Simple. • Not portable.
• Accurate. • Need of accurate levelling.
• Good repeatability. • Small range about
• Wide range of fluid can be 1000kN/m².
used.