The glass section is usually flat to provide strength and safety. The type of gauge glass utilized in this instance has a body made of metal with a heavy glass or quartz section for visual observation of the liquid level. If it is desired to measure the level of a vessel at higher temperatures and pressures, a different type of gauge glass is used. Gauge glasses made from tubular glass or plastic are used for service up to 450 psig and 400☏. Notice that the gauge glasses in Figure 1 effectively form a “U” tube manometer where the liquid seeks its own level due to the pressure of the liquid in the vessel. Figure 1 (b) shows a gauge glass which is used for vessels where the liquid is at an elevated pressure or a partial vacuum.
The height of the liquid in the tube will be equal to the height of water in the tank.įigure 1 (a) shows a gauge glass which is used for vessels where the liquid is at ambient temperature and pressure conditions.
In the gauge glass method, a transparent tube is attached to the bottom and top (top connection not needed in a tank open to atmosphere) of the tank that is monitored. Level GaugeĪ very simple means by which liquid level is measured in a vessel is by the gauge glass method (Figure 1). An example of the inferred method is a pressure gauge at the bottom of a tank which measures the hydrostatic head pressure from the height of the liquid. An example of the direct method is the dipstick in your car which measures the height of the oil in the oil pan.
Liquid level measuring devices are classified into two groups: (a) direct method, and (b) inferred method.
0 kommentar(er)
