Pressure Measurements (Lab Report)

1. OBJECTIVE
To measure gauge pressure through two different types of U-manometer orientation for Vertical and
Inclined.
To measure Vacuum pressure through two different types of U-manometer orientation for Vertical and
Inclined.
2. THEORY

The manometer readings must be adjusted by simple math and trigonometry to give actual readings.
They record a pressure difference and so the level of one tube must be subtracted from the other to give
actual pressure. One limb of the inclined manometer is set at an angle of 54° so this needs additional
calculation to give actual readings.
3. PROCEDURE
 For pressure test, extend syringe fully before you connect it to the pressure sockets.
 For vacuum tests, press the syringe piston in fully before you connect it to apparatus pressure sockets.
 For accurate comparison and to save time, you may use the Tee pieces and spare pipes to connect a
pressure or vacuum gauge and manometer at the same time.
 Make sure that the nozzle of the syringe is firmly connected.
 Slowly move the syringe in steps to create pressure gauge changes of 50 mm H2O.At each step, record
the change in both the gauge reading and the two manometer levels at the same time. Monitor the
manometer levels so that water is not split. Note: the pressure in the left hand tube of each manometer
is termed P1; the right hand tube is termed P2.
 From your results, calculate the adjusted readings for each manometer.