Obround sight glass is designed for visual inspection of levels inside a tank or a pipeline. The sight glass base is a weld pad designed to be welded directly to the pressure vessel. The glass is sandwiched between a sealing gasket and a cushion gasket held in place with a clamping flange. The cushion gasket is made from a material harder than the sealing gasket to ensure proper compression. Glass is clear, and made from tempered borosilicate. This window is suitable for the ASME pressure code requirements. The kit comes with all the hardware included. The Weld pad is flat. Per the customer’s request, the weld pad can be specified as curved to fit circular vessels of a particular diameter.

A liquid level gauge is an instrument that is used to monitor the fluid level in a tank or vessel. In old boiler-related jargon, this unit had traditionally been referred to as sight glass. Currently, it is typically referred to as a liquid level gauge, a much more descriptive label.

This type of glass features slots that effectively enhance the differences in refractive indices between liquid and gas above it, making the identification of the gas/liquid boundary much easier in the absence of other lighting arrangements.