What is McLeod gauge?
The shape of the Mcleod Gauge is similar to the mercury manometer which is the most common instrument used for the measurement of pressure. This Mcleod Gauge also has mercury inside it and the pressure measurement is done by seeing the changes in the mercury level.
How do you use a McLeod gauge?
To read a McLeod gauge, First, remove the mercury in the bulb & reference the column below the cut-off point so that gas can enter into the bulb & capillary. Where McLeod gauge is used? Mcleod Gauge is device used to measure pressure at very lower range upto 10-6 torr.
For what purpose Pirani gauge is used?
Pirani gauges are a group of indirect measuring pressure gauges which measure the thermal conductivity of the gas sample. Pirani gauges are typically used in the fine vacuum range (1 torr – 10-3torr), as this is the range where they achieve the best accuracy.
Which law is used in McLeod gauge?
Boyle’s law
The McLeod gauge takes advantage of Boyle’s law (the product of pressure and volume for a given quantity of gas remains constant if a constant temperature is maintained) to determine gas pressure within a range of 10 to 10-6 torr.
How much mercury is in McLeod gauge?
10 – 0.01mm Hg
Mcleod Gauge with Mercury 10 – 0.01mm Hg.
How does McLeod gauge measure low pressure?
McLeod gauge is essentially a mercury manometer in which a volume of gas is compressed before measurement. It operates by compressing a low-pressure gas of known volume into a smaller volume so that its pressure is sufficiently higher enough to be read.
What is the principle of Pirani gauge?
The Pirani gauge measures the vacuum pressure dependent thermal conductivity from the heated wire to the surrounding gas. The heated Pirani sensor filament is typically made of a thin (<25 µm) Tungsten, Nickel or Platium wire. As gas molecules collide with the filament wire, heat is transported from the hot wire.
What is Bourdon tube pressure gauge?
A bourdon tube pressure gauge is a mechanical pressure measuring instrument that reads the pressure without requiring any electrical power. It is generally used for the measurement of pressure from 0.6 to 7000 bar (8 to 10000 psi).
Which liquid is used in McLeod gauge?
mercury
The design of a McLeod gauge is somewhat similar to that of a mercury-column manometer. Typically it is filled with mercury. If used incorrectly, this mercury can escape and contaminate the vacuum system attached to the gauge.
What is thermocouple gauge?
The thermocouple gauge is one of a group of gauges working on the thermal conductivity principle. At low pressure, the kinematic theory of gases predicts a linear relationship between pressure and thermal conductivity. Thus measurement of thermal conductivity gives an indication of pressure.