Improving quality in both the glass, as well as the production process, was the focus of a number of sessions today during the biennial Glass Performance Days (GPD) ’19. The event is underway in Tampere, Finland, where presenters have been addressing a wide range of topics about changes and developments within the glass and glazing industry.
Two years ago here at GPD, several speakers discussed the subject of anisotropy, and it continued to see interest this year. Kai Vogel with Viprotron led the session titled “Optimized Furnace Settings with New In-line Anisotropy and Haze Measurement Methods.” He explained that anisotropy’s affect in tempered glass is visible in polarized light conditions is certain settings, such as at sea sides, the time before sunset, under certain angles and when wearing polarized sunglasses. Vogel said these appearances are caused by stress differences in tempered glass. One challenge the industry faces is that there are no guidelines or standards for quantifying anisotropy.
This, however is changing. For example, since 2016 in-line measurement devices are now in place, which can allow for the improvement of the tempering process for anisotropy and haze based on the measurement results.
Since 2018 two groups have been formed that are working to address what’s an acceptable level of quality. In the U.S. there is an ASTM group that’s working to define correct and repeatable measurement methods. In Germany, there is a DIN spec group that’s working to define criteria to quantify the quality level of tempered glass based on measurement results.
He also took a look at the details of the in-line measurement equipment, as well as the software features. The equipment, he explained, is located at the exit of the furnace, and includes high speed line scan cameras plus LED illumination. The software provides the calculation of optical retardation, different quality characteristics and precise calibration routines, among other features. It also generates quality reports automatically.
“Without proper calibration you will never gain good results,” he said, adding that systems are calibrated to ensure exact and reliable retardation measurement.
He said the system is always self-calibrating to adapt to different light and glass conditions, and that based on optical retardation measurements, different statistical methods are applied to quantify the anisotropy effects.
Another session, “Looking Beyond Industry 4.0 – The Digital Factory,” offered a look inside what the latest generation of factories looks like. Led by AJ Piscitelli from FeneTech, he explained that a digital factory is one that’s completely interconnected, from the machinery to managers, supervisors, suppliers, etc., in which all the data flows easily between them all.
“Pretty much any machine you buy today is networked,” said Piscitelli, explaining that most machines can receive production information. Some, he added, can provide local dashboarding/statistics and can also report back to the manufacturer or user.
He explained that data processing solutions can help reduce labor and gather useful information. For example, one can use the systems to monitor the production of the entire factory floor and see overall machine status and utilization, among other benefits. A company could then take the data from the machine and ERP system, workers and other areas and combine it all together.
“It gives you a more holistic look of everything,” he said. “… You can take data from machines and use it in future production planning … you can do better planning for maintenance,” he said.
These systems allow data and information to be combined into one location and can provide overall equipment effectiveness, including actual production, machine capacity, machine downtime, quality defects/rejects, etc.
This can also be beneficial to the company’s vendors, who can see consumables data from equipment and then resupply as necessary. He explained the ERP/inventory management systems can link in inventory data, as well.
“When you call vendors, if they have the visibility of what’s going on they can have those things preemptively ready for you,” he said.
For fabricators or manufacturers who want to implement this into their factories, he says it begins with a conversation with their machinery manufacturers. After that, if they don’t already have their own software production capabilities in house, they should then reach out to software companies to discuss