This equipment is often encountered when working on valve testing and is also often found in mechanical installations. The equipment is also called a Pressure Gauge.
What is a PRESSURE GAUGE?
A pressure gauge is a device used to measure fluid pressure (gas or liquid) in a closed tube. The units of this pressure gauge are psi (pounds per square inch), psf (pounds per square foot), mmHg (millimeter of mercury), inHg (inch of mercury), bar, atm (atmosphere), N / m ^ 2 ( pascal).
Before stepping into the discussion about pressure gauge, it's good to discuss the pressure itself. Pressure is divided into several, including:
ABSOLUTE PRESSURE
that is the pressure calculated based on the reference pressure of 1 atm. Absolute pressure is better known as PSIA. (PSIA = PSIG + Patm).
GAUGE PRESSURE
that is a positive pressure against a reference pressure of 1 atm, which means that this pressure is greater than 1 atm. The gauge pressure is better known as PSIG. In this condition, PSIG> 1 atm.
VACUM PRESSURE
that is negative pressure to atmospheric pressure or it could be said that the vaccum pressure is under atmospheric pressure so it is negative. PSIA <1 atm.
HYDROSTATIC PRESSURE
namely the pressure that occurs under water. This pressure occurs because of the weight of water which makes the liquid pressure. The pressure of a liquid depends on the depth of the liquid in a space and gravity also determines the pressure of the water. This relationship is formulated as follows: "P = ρgh" where ρ is the period of type of liquid, g (10 m / s2) is gravity, and h is liquid depth.
DIFFERENTIAL PRESSURE
that is, pressure measured against other pressures. PSID amount. To measure pressure / pressure there are several measuring elements, namely:
