Illus. 4
Big is trendy. Spring 2014 saw German glass finisher sedak GmbH & Co. KG commission the world’s largest digital flatbed printer for ceramic inks. It can print complex, multi-coloured pixel designs in high-resolution, photo quality onto glass sheets as big as 3.21 x 15.00 metres. The photo impressively shows the dimensions now possible.
Photo: sedak GmbH & Co. KG/Fotograf Hubertus Hamm

FOCUS ON EFFICIENCY AND QUALITY

Specialists article Nr. 6 GlassTec

The innovative power of glass machinery and equipment builders is a crucial factor for the performance of glass manufacturers and processors. These days their development efforts focus on maximum production efficiency, high product quality and, increasingly, on energy efficiency.

Posted 8 September 2014

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The requirements made of glass machinery and equipment manufacturers are more comprehensive and challenging than ever before. The increasing international competition in the glass sector, the associated price pressure, the growing number of different glass products and the strongly diverging batch sizes mean many glass converters are looking to high-performance technologies. To stand their ground against competitors the production of these enterprises must be highly efficient and they must consistently deliver the best possible product quality and ensure maximum flexibility. Another challenge is the rising weight of construction glass. Large-format glazing units are in fashion and the proportion of laminated toughened glass is also continuously on the rise. To efficiently manufacture these heavy large-format sheets processing machines and in-house and external logistics need to be modified. Moreover, the greater variety in types of glass requires a faster changeover between glass types – one prerequisite for this being optimised storage.


High Process Speed and Top Quality In view of the excess capacities prevailing on the glass market cutting production costs is often a matter of survival for glass-processing companies, especially in Europe. With a view to optimising the ratio between input and output, companies increasingly focus on consistent automation concepts, which are based on a holistic view of the operational environment and production workflow. Machine producers gear their machinery specifically to their customers’ needs. This applies to both stand-alone machines and to turn-key manufacturing lines. To achieve maximum efficiency extremely short cycle times are needed in industrial glass processing and finishing. However, this high treatment speed must not come at the expense of product quality and dimensional tolerances. It is not only automotive producers who expect absolutely precisely produced glass units – architects also require high precision. In April this year Franz Hauk, representative of the Technical Committee of the German Fachverband Fenster + Fassade e.V., demanded smaller tolerances for construction glass at the annual congress of the German Flat Glass Association (Bundesverband Flachglas e.V.). Due to their highly modern systems window and façade builders only had a very small tolerance area, said the fenestration and façade specialist, and added that exceeding it would lead to massive problems.		Illus. 1 Modern glass finishing machines must deliver the best product quality in shortest cycle times and blend perfectly with the company’s production workflow. The photo features the new XXL flatbed printer from glass finisher sedak in operation. Photo: sedak GmbH & Co. KG / Photographer René Müller

More Energy Efficiency
Another crucial aspect of state-of-the-art glass machinery production is their increased energy efficiency. Optimised workflows, the use of highly efficient engines and the latest radiator and convection technology in the manufacturing of safety glazing can all bring down companies’ energy consumption substantially. Process water preparation also plays a prominent role in view of ever stricter waste water regulations. The latest purification technology allows firms to save the environment and natural resources, reduce costs and improve machine performance.


Illus. 2 Highest speed: All components in Bystronic glass’ speed’line are designed for the highly efficient production of triple glazing units. This line allows triple insulating glass to be manufactured in the same time as double insulating glass on other lines. Photo: Bystronic glass		Innovative Insulating Glass Manufacturing One example of modern high-speed manufacturing technology is speed’line from the Swiss-German group Bystronic glass. In this insulating glass production line the process steps are geared optimally to the production of triple glazing units so that fastest cycle times are achieved. Thanks to speed’line’s triple glazing, units can now be produced in the same time that other lines take for producing double glazing units. The complete system includes two consecutive tps’applicator components for applying the thermoplastic spacers, the speed’assembler for quick assembly and gas-filling of the insulating units as well as the automatic speed’sealer. Only recently the company introduced new simulation software to the industrial working party Research & Technology of “Forum Glasstechnik”, the professional Association of Glass Machinery Builders in the German Engineering Federation (VDMA e.V.). This software allows engineers to precisely calculate the cycle times and costs for each individual glass pane while also displaying optimisation potential on existing production lines.

At that same meeting Leopold Mader of the Austrian glass machinery producer Lisec presented the latest production technologies, market potential and application benefits of triple glazing units from two-millimetre thin glass. Apart from reducing glass weight, using thinner glass also cuts primary energy needs in manufacturing by 30%, Mader reported adding that the changeover from previously customary 4-millimetre glass to 2-millimetre thin glass would result in substantial energy savings considering that in Germany alone 30 million square metres of insulating glass are produced every year. He said an additional value added was the smaller footprint for warehousing in addition to a higher light transmission of the insulating glass.

New Benchmark
A new benchmark concerning the size of glass-processing machinery possible today was recently created by the German company sedak GmbH & Co. KG. These multi-national glass finishing specialists are able to print complex, multi-coloured pixel designs in a high-resolution photo quality on extra-large format sheets measuring up to 3.21 by 15 metres with their new digital flatbed system for ceramic glass printing, which was commissioned in spring 2014. “With a resolution of 720 dpi we not only produce excellent prints. Our digital printing process also makes for a significantly thinner ink layer than obtained through screen or roller printing. This allows us to produce translucent prints and to design flowing transitions,” explains Bernhard Veh, CEO of sedak. The ceramic ink is sprayed onto the glass sheets by means of a plotter. After burning in the furnace the ink is permanently linked to the glass and scratch-resistant. These printed glass sheets can be processed further into insulating glass and laminated toughened glass and are even suitable for cold bending (lamination bending) during the lamination process.

Trend towards Vertical Machines
A current trend in finishing glass surfaces and edges of glass doors and textured glass, for instance, is the use of vertical machinery. Their advantage: they have a markedly smaller footprint than machines with a horizontal layout. An example of this new type of machinery is the vertical drilling and grinding machine Vertmax made by Italian glass machinery manufacturer Intermac, a company of the Biesse Group. By company accounts, the new machine scores not only with its new user-friendly operator software but also with its finishing for float and laminated glass. Furthermore, the system, it is said, requires only minimal set-up times and it ca drill, mill, grind and polish glass for a multitude of applications quickly and with highest precision in an automated working process.

Illus. 3 Optimised residual sheet storage: Thanks to Hegla’s SGG-ReMaster any glass sheets left over after cutting, breaking and parting can be stored without the need for any additional space and can be automatically re-introduced into manufacturing on demand without interrupting the production process. Photo: Hegla GmbH & Co. KG


High-Powered Laser Technology The sector feels that laser technology also holds great potential for flat glass finishing. Here the German firm Cerion GmbH is among the pioneers on the market. This company has continuously developed its plant technology and now offers machines that can perform internal or external engravings – depending on the layout – or even both using solid state and/or CO₂lasers. The company’s c-vertica series comes in various sizes and configuration levels. From small systems for finishing door-sized formats all the way up to laser machines for sheet formats as big as 6,000 x 3,300 x 100 millimetres. Add-on modules allow the format to be enlarged by 3,000 mm each. With laser machines made by Cerion, float and laminated toughened glass can be treated as well as mirrors and other coated glass. Even surface engravings on TSG no longer pose a problem. Additionally, laser technology is suitable for de-coating flat glass or applying transparent anti-skid textures (certified according to R9 and R10). Thanks to the high degree of automation, entire product series can be processed with minimum personnel intervention.		Illus. 6 Flat glass can now be finished efficiently and largely automatically with the help of state-of-the-art laser systems. Depending on version, Cerion GmbH’s c-vertica makes it possible to engrave the surface or the inside of flat glass, even in very large formats. A combination of both finishing options is also available. Photo: Cerion GmbH

Reliable Quality Assurance
A key issue to be addressed in glass production and processing still is quality assurance. Here state-of-the-art scan systems provide ultimate assurance for glass manufacturing and processing. To Ulrich Bauereiß, Sales Manager of Dr. Schenk GmbH, a specialist for industrial measuring technology, the “true benefit” of automatic surface inspection in glass manufacturing lies in process optimisation. By evaluating the data furnished by these systems flaws in the manufacturing process can be identified and eliminated. Anything else was “purely sorting out” to him, as Bauerreiß explained last year in the Industry Working Party Research and Technology of the VDMA Glasforum.

Rainer Feuster, Sales Manager at Viprotron GmbH, a manufacturer of visual quality inspection devices for flat glass finishing, mentions three categories of flaws typically found in the visual quality of construction and insulating glass during inline inspections: flaws with clear contours such as scratches, inclusions and bubbles, defects with a low contrast such as roller waves, hairline scratches and impurities and lamination defects such as brush marks, deposits and surface damage. With its various high-quality scanner products Viprotron offers inspection systems that are specifically geared to the various flat glass processing segments and take the special requirements of each process into consideration. The latest generation of this scanner technology reveals even the smallest of defects.

What other technological innovations glass machinery and equipment producers from throughout the world currently have in store for glass producers and processors will be showcased in Düsseldorf at glasstec 2014 from 21 to 24 October. This the most important international trade fair for the glass sector will present the entire spectrum from glazier-crafted to industrial glass processing for the areas of flat glass, hollow glass, solar glass as well as various types of special glass. Efficiency and quality will play a pivotal role at the trade fair. The latest technology trends in machine and equipment building will be centre stage at the VDMA Symposium held on 22 October as part of the Special Show “glass technology live” at glasstec. The event will focus on plant engineering for processing and finishing glass. Special emphasis will lay here on quality and process control.


Illus. 5 The latest trend – the vertical glass grinding and drilling machine Vertmax from Italian machine builder Intermac is very efficient, multiple-purpose and has a smaller footprint than horizontal systems. Photo: Intermac		Sustainability gaining in Importance The sustainability theme is gaining more and more importance for glass machinery and plant builders. Here, too, German machine builders are at the forefront. In 2011 the German Engineering Association (Deutscher Maschinen- und Anlagenbau e.V.) founded the sustainability initiative “Blue Competence”. This network now counts over 400 enterprises including renowned glass machinery and plant manufacturers such as Grenzebach, Hegla, Isra Vision, Bohle and Zippe. As members of this initiative the companies pledge compliance with a total of eight criteria. These cover all relevant aspects of sustainability ranging from in-house production to awareness-raising amongst customers. By joining the Initiative, which is open to all European machine builders, enterprises make a clear statement on environmental protection and CSR matters. Once they boast the Blue Competence Label they can stake a strong “sustainability claim” against competitors. More information : www.glasstec.de