Sight glasses are highly engineered products. This white paper provides expert advice on how to select a sight glass able to meet the needs of your particular critical application. Six conditions, and how to design for them, are addressed.
Sight glass applications require varying levels of consideration during the design phase. In all applications, sight glasses will be subjected to forces involving pressure, temperature, thermal shock, caustics, abrasion, or impact. It is critical to ensure that the design approach to each application takes these conditions into account.
Sight glass failures can create costly downtime, lost production, and even safety concerns. In a system made primarily of metal, the weak spots are generally sealing joints and glass. Typically, the failure of a sight glass on a piece of equipment or within a piping system will halt the whole process until the equipment can be repaired or replaced. Moreover, this failure may lead to scrapping the process media.
Extreme forces, whether internal or external, can have a detrimental impact on the visibility and strength of the glass components. Even minor cracks, scratches or abrasions of the glass can be a source of weakness within the glass, which will most likely lead to failure.
