Sight flow indicators

They consist of a robust borosilicate glass viewing section housed in a metallic body with flanged or threaded ends, allowing easy installation in new or existing lines from small laboratory services to large process mains.

The glass tube or window offers full 360° visibility, so operators can instantly detect whether liquid is present, if it is clean or contaminated, and whether any gas bubbles or suspended solids are passing through.

Borosilicate glass 3.3 delivers excellent resistance to thermal shock and aggressive chemicals, making these indicators suitable for acids, solvents, and high purity media in demanding industrial environments.

Depending on the application, the indicator can be supplied as a plain view type or fitted with a PTFE flap, spinner, or rotor to enhance motion visibility at low or variable flow rates.

Typical operating conditions cover pressures up to several tens of bar and temperatures from cryogenic service to around 200 °C, limited mainly by gasket and metal body materials.

Sight flow indicators are widely used for pump start up checks, confirming dosing or CIP flow, monitoring condensate return, and verifying media changeovers in chemical, pharmaceutical, food, and water treatment plants.