Gauge Pressure
The most well-known pressure reference is Gauge Pressure which is connoted by a ‘g’ after the pressure unit, for example, 33 psi g. It is the pressure relative to barometric or atmospheric pressure; it is positive for pressures above atmospheric pressure and negative for pressures that are below atmospheric pressure.
This shows that the pressure estimated is the ‘Total pressure (minus) Atmospheric pressure. Atmospheric pressure is not taken into account in this pressure reference. As such, gauge pressure utilizes atmospheric pressure (14.7 PSI), as its zero point. At times, it is alluded to as ‘Overpressure’.
Machines that use gauge pressure are Well pumps, Air compressors, and Tire gauges. There are two kinds of Gauge reference pressure:
- Vented Gauge (vg)
- Sealed Gauge (sg)
Converting 33psi g to an absolute pressure
Example: If the gauge pressure is 33psi what would be the corresponding absolute pressure?
Answer:
A gauge pressure can be changed over into an absolute pressure by including it in the ongoing perusing of atmospheric pressure. For instance on the off chance that the atmospheric pressure is 14.7psi absolute, then the 33 psi gauge would be converted to 47.7 psi absolute.
Difference Between Gauge Pressure and Absolute Pressure
Pressure is the force per unit area applied toward a course perpendicular to the outer layer of an item. Numerically, it is represented with a ‘P’. To keep it precise, it is an amount of force following up on a unit area. The simple equation for pressure is P = F/A where P is Pressure, F is Force, and A is Area.
The SI unit for pressure is measured in Pascals (Pa). Other non-SI units are bar and PSI. There are two types of references to quantify pressure,
- Gauge Pressure
- Absolute Pressure
Table of Content
- Gauge Pressure
- Absolute Pressure
- Difference between Gauge Pressure and Absolute Pressure
- Sample Questions