A modern industrial sight glass is a window that looks into a specific location of an industrial process. Often, the process operates at high pressure, temperature or contains fluids that cannot be released into the environment. A properly specified sight glass permits visual inspection into such processes while maintaining a significant margin of safety with respect to whatever risk the processes carries. At the beginning of the industrial age, they became wide spread due to lack of other viable technologies for measuring fluid conditions in various processes. They still remain popular in countless manufacturing, chemical, food processing and energy facilities, in spite of availability of a great variety of measuring technologies. The reliability and the information content of visual inspection cannot be rivaled by any other measurement method in many applications. Therefore, modern designs serve alongside automated instrumentation, and continued to be developed for ever expanding roles.
This web site's goal is to educate the engineer, management and process worker on the safe installation and maintenance of a sight glass window, and how to make correct design decisions for specific applications. This site will help you select and configure the proper sight glass, learn how to perform routine maintenance and inspect for leaks and other problems before they develop.