Glass tempering is one of the most widely used thermal processes in the glass industry, transforming standard float glass into a stronger, safer, and more reliable product for architecture, façade systems, interiors, furniture, and automotive glazing. In a recent technical overview, Keraglass highlights how modern tempering technology, particularly through Keraglass Vision furnaces, can deliver higher production stability through advanced temperature control, intelligent software, and optimized cooling performance.

Controlled Heating: The Critical First Stage

The tempering cycle begins inside the heating chamber, where glass is gradually brought to approximately 640°C, close to the point where it becomes malleable. Heating is achieved through a combination of radiation from electric heating elements and convection, allowing temperature to be distributed across the entire surface.

Keraglass underlines that uniform heating is essential, because even small temperature deviations can lead to optical distortion, inconsistent stress distribution, or breakage during quenching. This becomes even more sensitive when processing next-generation Low-Emissivity (Low-E) glass, where coatings and thermal behaviour require stable conditions and precise control. Physically, this phase occurs within the glass transition temperature range, where glass shifts from rigid to plastic without losing cohesion.

Keraglass Vision: Heating Precision Through Intelligent Regulation

To reduce variability and improve repeatability, Keraglass Vision furnaces use a heating approach designed for high consistency and efficiency. Key elements include independent heating zones with dedicated controls, automatic regulation of heating kinematics and temperature via advanced software, and minimal thermal deviations across different glass sizes and thicknesses. This level of stability is intended to support higher yield and reliable output, especially during complex or mixed production runs.

Tempering and Cooling: Where Strength Is Formed

Once the glass reaches the correct temperature, it enters the tempering and cooling section. Here, calibrated high-pressure air jets rapidly cool the outer surfaces, while the core remains hot briefly. This controlled thermal shock creates permanent internal stresses, compression at the surface and tension in the core, raising mechanical strength by four to five times compared to annealed glass.

Optical Quality and Safety Performance

Keraglass also points to the importance of optical quality, emphasizing uniform cooling to improve stability and reduce iridescence. When controlled correctly, tempered glass delivers high impact resistance, strong dimensional stability, and enhanced safety: in case of breakage, it fractures into small, non-cutting fragments.

By combining precise thermal management, advanced controls, and an optimized air-blowing system, Keraglass positions its Vision technology as a solution built for long-term performance and consistent high-quality tempering results.