Flat glass - cold end


Worldwide, 95% of the flat glass is produced in the so-called float process. The float glass production is an endless continuous process. The doughy-liquid molten glass is continuously fed onto a long bath of liquid tin on which the glass floats and spreads uniformly as a film. The solidified glass at the cooler end of the bath that still has a temperature of approximately 600° C is pulled out continually and passes through an annealing lehr in which it is cooled down stress-free.

The so-called "cold end" of the glass production begins with the camera-based investigation for defects and the subsequent optimized cutting (longitudinal and lateral cutting) that depends on the investigation result. The glass sheets are then distributed to various transport belts, from where they are stacked and passed to any further required processing steps (e.g. coating).

Example solution

The "cold end" of the flat glass production: cut, transport, distribute and stack

Siemens supplies optimized solutions for the complete electrotechnology for flat glass production. Whereas the process automation dominates in the raw material preparation and in the furnace process, the drive technology plays a particularly important role downstream of the forming process.

Transporting, distributing and stacking depends on the high accuracy of the conveyor tracking and the path interpolation. The Siemens solution provides high productivity thanks to SIMOTION axis synchronization. The Handling Toolbox ensures short engineering times without specific robotics know-how.

Technology overview

Siemens motion control solutions are deployed in all processing steps for glass sheets

Glass forming (the so-called "top rollers" are lowered into the glass, affect the flow speed and so the glass thickness)

Stress-free cooling in the annealing lehr

Cutting (lateral and longitudinal)

Transporting and distributing



  • Continuous flat glass production
    thanks to the consistent redundancy concept

  • Plant-wide transparency
    thanks to networking: Access from the higher-level controller of the glass line to all process steps of the glass line down to the drive level (plant-wide automation)

  • Precise and fast motion control of the complete "cold end"
    thanks to the SIMOTION motion control system: cutting (lateral and longitudinal), transporting, distributing and stacking

  • Safety for persons and machines
    thanks to the integrated safety technology