Embed Size (px)
Citation preview
Glasstec 2018By: Kevin Yin – BuroHappold EngineeringIf you are a member of the SFE and would like to go to Glasstec next year, or any other Facade based exhibition or event and would be willing share your experiences in a short technical appraisal like the one below, get in touch as we have a fund available to assist for our members, [email protected] five notable developments at the Glasstec trade fair:
● Online glass scanners, particularly for anisotropy● Increased availability of large format glass● Vacuum glazing developments● Advancements in thin glass● Nickel sulphide inclusion scanner
About the event:Glasstec is a bi-annual glass trade fair where manufacturers and suppliers of glass and glass production equipment show case their latest technology and products. There are also research academic organisations displaying their developments and prototypes. This year’s Glasstec took place between 23rd and 26th October, and attracted manufacturers, suppliers and research groups from around the world. The glass products on show ranges from art glass, to glass for automotive industry, internal glass partitions, and building facades with products designed for building facades making up a significant portion.Online glass scanners, particularly for anisotropy:Anisotropy in heat treated glass has long been a concern for building owners and designer due to the unpleasant visual effect under certain light conditions. Various attempts were undertaken by glass industry to reduce the anisotropy by glass manufacturers in response to the demand of the market. To assist the effort of glass manufacturers, companies from Europe and North America have developed scanners to measure anisotropy. These scanners can be installed on glass production line. The scanned image can even be monitored remotely through internet connection. Several glass manufacturers across Europe have installed these on-production-line scanners to their production lines. This will help them adjusting the toughening oven parameters to control and reduce anisotropy. In project execution, the anisotropy issue may remain a difficult topic for specifiers and contractors due to the ambiguity of the acceptance criteria. Standards are currently being developed to define acceptable levels of anisotropy through measurement of the optical retardation of light due to stresses within the glass. One of the challenges here is that pattern as well as intensity are relevant in such evaluations. There is further development need in this area to establish a consistent evaluation method that can be implemented in building projects. For now, comparative measurements are becoming feasible to control these effects.
Figure 1 – Example of anisotropy scanning
Increased availability of large format glass:
Following the announcement of the availability of 20x3.2m glass by Sedak earlier this year, Saint Gobain, working with their processing partner Thieleglas, added their name on the list of large size glass suppliers by displaying their 18mx3.2 flat laminated glass in Glasstec.The display of expanded availability is also seen in curved glass area. Spanish manufacture Cricursa showed a large single curved hot bend laminated glass with approximate 8m arc length and 3m height. Northglass from China showed their version of curved glass in similar size and declared that they are able to supply single curved glass up to 18m height with 3.6 arc length or 4m height with 8m arc length. Large size glass are usually limited to very high profile projects, but the demand is increasing driven by ambition of building owners and architects and the development of glass engineering design. The widening availability is a response from the glass industry to this growing demand.
Figure 2 – Large curved glass by Northglass (left) and Cricursa (right)
Vacuum glazing developments
Widening availability is not limited to large size glass in this year’s Glasstec. Several manufactures brought their vacuum glazing to the trade fair. Small samples from a few Chinese manufacturers were on display. From European manufacturers, Guardian was promoting their vacuum glazing for use on fridge doors by comparing the performance, clarity, and weight of vacuum glazing with typical triple glazing with double low E coating. AGC also displayed their vacuum glazing sample and bench marking to the typical insulated glazing units to demonstrate the advantages. The technology of vacuum glazing has been in existence for many years.
Cost and proof of longevity have been the main obstacles for wide application in buildings. With more manufacturers investing in vacuum glazing, it may be expected that the cost will be more affordable and more technical information will be available for engineers when making decisions. Advancements in thin glass
Thin glass with thickness less than 2mm is typically use in electronic industry, such as display screens. The technology is moving to construction industry. In addition to the thin glass products already on the market, which are primarily designed for electronic industry such as Gorilla glass by Corning and Dragontrail by AGC Japan, AGC Europe showed their thin glass brand named Falcon glass. The glass is produced by float process, which opens the door for application in facades due the large size achievable and relatively lower cost compare to the typical thin glass. The new possibility of using thin glass in buildings has attracted the interest of a few universities. TU Darmstadt built a thin glass robot that uses thin glass as the legs of the robot. TU Delft also showed some concept models that incorporate thin glass in adaptive façades, as well as cold bend thin glass forming curved surface over cable net structure. These research projects are taking the advantage of thin glass with combined load bearing capacity and flexibility. Another stream of thin glass application is to explore the strength of chemical strengthening and low weight of thin glass. TU Delft showed prototype model of sandwich panels with thin glass skin and 3D printed plastic core. The industry, including manufacturers and researchers, are embracing this opportunity of innovation. It may not be long before the thin glass application providing the design options that are not currently possible for architects and façade engineers.
Figure 3 – Thin glass in prototype of robot (left) and cable net structure (right)
Figure 4 – Thin glass sandwich panels with 3D printed plastic core
Nickel sulphide inclusion scanner
Spontaneous damage due to Nickel Sulphide (NiS) inclusions in toughened glass has been a known problem for decades. In practice, the majority of glass manufacturers do not provide warranty against NiS damages of toughened glass even though the glass is heat soaked. The residual risk of NiS damage of heat soaked toughened glass may be a concern on high rise building for designers. TU Darmstadt claimed that they have developed a method and equipment to scan the glass identify NiS inclusions. The development of the technology may change risk profile in relation to the use of toughened glass.ConclusionOverall, this year’s Glasstec continue to bring the latest development in glass industry together to one place pushing the boundaries of manufacturing and engineering technology. The trade fair also sees manufacturers displaying their latest expansion of production capability. The next Glasstec trade fair is scheduled on 20-23 October 2020. For façade engineers, the trade fair is a place to keep up with the latest development in glass industry, and broaden the minds with the engineering development that may not seem to be applicable today, but will bring innovation in façade design in the future. This short article only covers some of the salient developments showcased at the Glasstec tradefair and many other products and innovations were on display. https://www.glasstec-online.com/
If you are a member of the SFE and would like to go to Glasstec next year, or any other Facade based exhibition or event and would be willing share your experiences in a short technical appraisal, get in touch as we have a fund available to assist for our members, [email protected]
