Spontaneous breakage, splintering, pronounced over- and undercuts: The rising use of laminated glass in insulating glass production, coupled with inconsistent raw material quality, poses a significant challenge for maintaining continuous, high-quality production. Discover how LiSEC overcomes these obstacles with its selective infrared heating (SIR) technology — and how you can benefit from it.
Due to its composite nature, laminated glass is cut with one or multiple fixed cutting bridges. The lami cutting process consists of two steps: first, the glass panes are scored and split, then the gap is pulled apart and the PVB foil between the glass panes is cut with a blade. Due to the limited elasticity of PVB at room temperature, the industry practice of heating the foil before opening the gap has become established. This reduces the force required and ensures a perfect cut edge without delamination.
The patented SIR heating system from LiSEC is particularly reliable and fast thanks to the curved infrared radiant heaters. The 900 mm long, sequentially arranged infrared heating modules with heated radius ensure seamless, rapid heating of the PVB foil, without thermal stress zones at the transition points between two heating elements.
Another advantage of the SIR heating technology is its ability to adapt flexibly to the specific properties of the glass/PVB foil/glass laminate used in the production. Glass and PVB foil absorb infrared radiation in different wavelength ranges. This technique allows for precise heating of the PVB film, avoiding unnecessary heating of the glass and therefore preventing any thermal stress.
Each 900 mm heating module can be individually activated based on the length of the glass being processed. This selective operation significantly reduces energy consumption compared to traditional methods. Moreover, the compact and transportable nature of the 900 mm heating elements ensures they are not only easy to store but also contribute to high system reliability with minimal spare parts and operating expenses!
Thanks to SIR, heat stress in the glass is a thing of the past:
Since its initial introduction at the glasstec 2018 in Düsseldorf, all VSL-A laminated glass cutting machines from LiSEC have been using the patented SIR heating system as standard.
A retrofit kit for the SIR heating system is available from longlife@lisec.com for older LiSEC laminated glass cutting bridges (VB-33, VB-37, VB-45 and VB-60). With SIR retrofitting on existing VB systems, the heating time can be reduced to as little as 7 seconds for 44.2 laminated glass. This ensures higher output for existing systems, while also saving energy.