We Supply both tubular and flat sight glasses of borosilicate glass (pyrex) and quartz. This includes heavy wall glass tubing for pressure / vacuum and lubrication applications, like oil sight glass or a boiler sight glass. Many sizes and diameters of sight glasses are available with redline and heavy wall variations. Both ends of the sight glass are ground square. Pipe sight glass with pipe flanges is also available.

1. Rotameters.
The float is inside a tapered tube. The fluid flows through the annular gap around the edge of the float. The restriction causes a pressure drop over the .float and the pressure forces the float upwards because the tube is tapered, the restriction is decreased as the float moves up. Eventually a level is reached where the restriction is just right to produce a pressure force that counteracts the weight of the float. The level of the float indicates the flow rate.

2. Sight Glass Level Gauges.
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. The height of the liquid in the tube will be equal to the height of water in the tank.