Sight glasses or water gauge is a type of level sensor, a transparent tube through which the operator of a tank or boiler can observe the level of liquid contained within.
Common Sight Glass Applications
There are a number of uses for sight glasses and the varying forms they can take. A sight glass is especially useful for monitoring fluids in pipe systems, keeping an eye on the pressure in boilers, and ensuring that the pilot lights and heating elements are functioning properly in heating systems.
Sight glasses are used across a huge range of industries, including:
- Utilities and power
- Food and beverage
- Wastewater treatment and management
- And chemical/petrochemical
The most well-known application for sight glasses is monitoring fluids, since companies of all kinds must monitor fluids to ensure optimal quality and safety; after all, everything from petrochemical industries to craft breweries work with liquids.
This makes sight glasses critical components for ensuring operations run smoothly and safely. Liquid level gauges, another form of sight glass, is often used in industries with storage tanks or containment systems designed to mix or ferment.
Sight glasses and sight glass windows, as mentioned earlier, are commonly used in industries that use pressurized systems; steam boilers and steam generators are found in a wide variety of industries, such as utilities and power generation, cement production, food and beverage, and dry cleaning.
All processes that require pressurized systems or vaporization use sight glass windows in some manner. They are used for monitoring liquids and ensuring optimal safety. Boiler systems also use a more specialized type of sight glass, called boiler sight glass. It is used to monitor the pressure within.
Industries that utilize heat or heat transfer make use of sight glasses as well. Many of the heating systems in these applications contain a viewport or sight port to ensure the system is functioning properly.
In these scenarios, the operators certainly can’t look directly inside the heating system. This is to make sure the pilot lights or heating elements are still working. It is why the viewport is such a critical component in the overall system.