German handling and processing technology specialist Grenzebach is claiming a world record and world first for the kilometre-long cutting of flat glass with laser. The results were displayed at the Glasstec Laser Innovation Forum. Glass customers downstream stand to benefit from this technology.

Grenzebach carried out extensive tests for online cutting with laser. A change of the colour of the glass melt at Pilkington’s Weiherhammer plant provided a good opportunity for an initial test run of 100,000 squares metres of glass ribbon. The expectations were ‘totally fulfilled’ during the test: The very precise continuous scoring of the glass ribbon stopped exactly to the millimetre at the defined cutting end.

In tests, various types and sizes of glass were cut longitudinally by laser in realtime float glass manufacturing. An outstanding result of laser cutting is the smooth and clean glass edge. Much reduced levels of glass dust minimise the likelihood of scratches created by glass chips Flaking and micro-cracks are virtually eliminated. Furthermore, the edge stability of laser cut glass is three times higher than with standard cutting technology and twice as high as conventionally cut and ground panes. As a result the breaking strength of the glass sheet is many times greater.

Cracking of glass on the line or in the glass store will be reduced. Laser cutting is not influenced by the glass stress so that only one edge cut is required. The initial rough cut can be eliminated allowing the width of the glass ribbon to be reduced by 10 cm. As a result considerable cost savings in both material and energy will be achieved.

Grenzebach engineers are now working on developments to apply laser cutting for glass 15mm thick and upwards. The laser cut will then snap the glass automatically on a standard edge trim conveyor.

The Grenzebach laser cutting device can be integrated into all existing float cutting bridges, says the company.

Previously, only thin glass could be cut by laser; alternatively the processing speed had to be extremely slow and the glass had to be cut on special stationary cutting tables.

Elsewhere at Glasstec, Grenzebach emphasised its technology for cutting and stacking of flat glass, including load sharing robots that can work in tandem taking large glass sheets weighing up to 600 kg out of the production line, and also work separately.

Source

Glass Age