Mercury Manometer
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ScribdTranslationsMercury Manometer
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ScribdTranslationsUSE OF THE WATER MANOMETER ON MERCURY
1. OBJECTIVE:
2. THEORETICAL FOUNDATION
2.1 Manometers:
The manometer is an instrument used for measuring pressure in the
fluids, generally determining the difference in pressure between the fluid and the
local pressure.
When manometers must indicate rapid pressure fluctuations, they are usually
use piezoelectric or electrostatic sensors that provide a response
snapshot.
It should be noted that most pressure gauges measure the difference.
between the fluid pressure and the local atmospheric pressure, then it must be added
this last one to the value indicated by the manometer to find the absolute pressure.
When a negative reading is obtained on the manometer, it is due to a vacuum.
partial.
Bourdon pressure gauge: Mechanical instrument for measuring pressure
that uses a curved or twisted metal tube as a sensitive element,
flattened cross section. One end of the tube is closed, and the pressure
what is going to be measured is applied from the other end. As the pressure
As it increases, the tube tends to acquire a circular section and straighten out.
free end movement (closed) measures the internal pressure and causes the
needle movement.
Manometer of column of liquid
Double liquid column used to measure the difference between pressures
of two fluids. The liquid column manometer is the base standard for
the measurement of small differences from pressure.
The two main types are the glass tube manometer, for the
simple indication of the pressure differences, and the manometer of
mercury with a metal container, used to regulate or record a
difference of pressure o a current of a liquid.
The three basic types of glass tube manometers are the U-tube manometer,
the ones with an inkpot and the ones with an inclined tube, which can measure vacuum or pressure
manometric leaving a branch open to the atmosphere.
U-tube manometer: If each arm of the manometer is connected to different
pressure sources, the liquid level will rise in the branch with lower pressure
and will decrease in the other. The difference between the levels is a function of the
applied pressures and the specific weight of the liquid of the instrument. The area
The section of the pipes does not affect the difference in levels.
Usually a graduated scale is fixed between the two branches to facilitate
the measures.
The U-tubes of the micromanometers are made with glass U-tubes.
precision calibration, a metal float on one of the branches and a reel
of induction to indicate the position of the float. An electronic indicator
Potentiometer can indicate pressure changes of up to 0.01 mm of
water column. These devices are used only as laboratory standards.
2.2 Pressure
In mechanics, pressure is defined as the force per unit area that
exert a liquid a gas o perpendicularly said surface. a
Pressure is usually measured in atmospheres (atm); in the international system of
units (SI), pressure is expressed in newtons per square meter; one newton per
square meter is a pascal (Pa). The atmosphere is defined as 101.325 Pa, and
it is equivalent to 760 mm of mercury in a conventional barometer.
Pressure is defined as a force per unit area, where the area is
perpendicular to the force where the basic unit of pressure is the pascal that
corresponds to one Newton (unit of force) per square meter (Area).
=
Á
for the practice, the following manometer equation is used:
+ ( ) −
+ ∆ℎ ( ) ∆ ℎ −( ) = P(2)
With it, we can find the difference in pressures that exists at the ends of the tubes.
since they are of the same length.
We take manometric measurements and Pa is the pressure of the atmosphere and therefore
it would be equal to 0, the equation is as follows:
= ( − ) + ∆ℎ( − ( )) 3
= ∆ℎ( − ( )) 4
Due to gravity, we can say that density is equal to the specific weight of the
material, then:
=( − )∗ ( ∆ℎ
∗ ) 5
Using the following parameters:
∆ℎ = 2− 1
= 9.79 ⁄ (Gravity
2 in Bogotá)
⁄
= 1000 kHz 3
⁄ 3
13600 kWh
The Bourdon manometer tells us the pressure inside the piston so it can be
to know what the difference is between the pressures that were found and the established one.
3. MATERIALS
Dead Weight Pressure Gauge Calibrator brand EDIBON
Masses
Piston
Funnel
250 ml of water
2 long hoses for the hydrostatic bench
Mercury manometer from the EDIBON hydrostatics bench
4. PROCEDURE
Place the hose at the bottom of the cylinder.
Fill the cylinder with water until its level reaches the upper connection.
Fill the water hoses, ensuring that as much as possible remains empty.
bubbles inside them.
Close V7, V8, V9, V10, V13
Connect the longest hose from V8 to V14
Connect the shortest hose from the bottom of the piston,
up to V7
Fill the water cylinder until reaching the top outlet, now place the
piston inside the cylinder ensuring that the water level is correct
Open valves V7, V8, V9.
Locate the masses of 0.5Kg, 1Kg