Manufacturer of infrared measurement devices Optris GmbH has developed a system for temperature monitoring during thermal tempering that is compatible with glass that has a very low emissivity coating.

Used to produce products such as single-pane safety glass (SPSG), thermal tempering is the process of influencing the physical properties of flat glass with targeted heat treatment.

Precise maintenance of oven temperature, depending on the type and thickness of the glass, is crucial for the desired quality of the end product. This involves both the exact temperature and the most homogeneous temperature distribution possible within the glass panes.

Optris’ measuring system based on the PI 640 IR camera can be used on any glass tempering system thanks to selectable optics with different aperture angles.

To meet the challenge of using infrared measurement technology on insulating glass that has a coated side with a very low emissivity (such as energy efficient Low-E glass, commonly used for windows and facade components), Optris offers its Top Down GIS 640 R system:

Above the glass, at the exit of the oven, a PI 640 infrared camera is installed, which quickly determines with high resolution the temperature distribution of the individual panes over the entire system. Below the glass – i.e. on the side without the Low-E coating – a CT G5L pyrometer reproducibly measures the exact glass temperature. The individual pixels of the IR camera image are referenced to this measured value. This enables automated emissivity correction for standard and Low-E glass. In addition to determining the temperature distribution, the system also calculates the glass surface area. Both the infrared camera and the pyrometer are equipped with a digitally controlled optics protection system.

Optris supplies the Top Down GIS 640 R as a pre-assembled system for installation on glass tempering equipment. Delivery also includes a compact control cabinet with all electronic and control components as well as all necessary cables.

Unlike traditional line scanner systems, the exact alignment of the scan line can be performed by the software with the camera-based GIS 640 R system – exact mechanical positioning of the system above the oven is not necessary.

www.optris.global

View Optris’ presentation in the Virtual Marketplace: www.glassworldwide.co.uk/virtual-marketplace. The full version of the above news has been published in the May/June issue that has been posted globally and is available to read free of charge in the Digital Archive (sponsored by FIC) at https://www.glassworldwide.co.uk/Digital-Issues