The LUMISTAR Threaded Process Sight Glass Assembly is designed to provide clear visual access to the inside of tanks, pipelines and closed process equipment. It is suitable for applications where operators need to monitor liquid levels, product movement or general process conditions without opening the equipment during operation.

The assembly typically consists of a weld-in nozzle, a threaded retaining nut, a sight glass disc and sealing components. The nozzle is welded into the equipment wall or pipeline connection, while the retaining nut secures the glass assembly in position. This construction provides a compact viewing point for compatible process systems and allows the glass and sealing arrangement to be specified according to the installation requirements.

Different glass materials can be considered to suit the operating environment. Thermally toughened soda-lime glass may be suitable for certain moderate-temperature applications, while borosilicate glass is commonly selected where better thermal-shock resistance and higher operating temperatures are required. The final glass specification should be determined by the process medium, pressure, temperature and equipment design.

The threaded connection is designed with reference to fittings similar to DIN 11851. Since similar-to-standard designs may differ in dimensions and sealing arrangements, the connection profile, nominal size, welding dimensions and mating components should be checked before installation. Compatibility with an existing DIN 11851 connection should not be assumed without dimensional verification.

The reference design uses a flat gasket and an O-ring sealing arrangement. Depending on the configuration, possible sealing materials may include EPDM, silicone, FKM, PTFE or other suitable options. Material selection should take into account the process fluid, cleaning chemicals, temperature, pressure and any required cleaning or sterilisation procedures.

For the referenced design, the maximum operating pressure is listed as approximately 6 bar, with higher pressure ratings requiring specific review. The maximum reference operating temperature for borosilicate glass is up to 280°C, while soda-lime glass is listed up to 150°C. These figures are material-related reference values rather than a guarantee for the complete assembly; the allowable operating limits must be confirmed for the supplied size, glass, seals and metal components.