How to change the tempering process control from settings to specifications


he glass tempering is the process which can be made in many ways to get tempered glass which meets the standards. Selected way is usually chosen individually by an operator and almost always based on the experience instead of science. Complexity of operation increases especially in environments where more than one operator is operating the line, which can lead to making process decision based on different logic in different shifts.

To tackle this challenge, a centralized process model has been developed that controls the whole tempering process. It helps to increase repeatability of the tempering process. This automation-based process model provides a stable platform to develop the tempering process considering multiple aspects in the future.

As an example, the tempering process is driven by regional and factory standards, factory targets and end-user demand. Process target can be for example high production rate, high yield, low anisotropy, or low deformations. It is difficult to achieve all these targets at the same time, usually at least one factor needs to be sacrificed to achieve the others.

What if the process is for example controlled by telling the machine what is the target of product?

With good understanding of the process and increased number of measurements in the process the automation level can be increased. Increased automation level helps to adjust tempering parameters depending on the internal and external variables. With all automated information tempering machine would recommend the loading pattern and set process parameters to meet the desired specification of product.



An enhanced model of thermo-mechanical loading on a Vacuum Insulated Glazing


In the EU, the use of high-performance insulating windows has the potential of reducing the total energy consumption of the building sector by 40% by 2050. However, this is only possible if the aged and existing building stock is retrofitted with such insulating windows. The Vacuum Insulated Glazing (VIG) is a technology that has the potential to impact the whole building stock in the EU because of its thin profile and low thermal conductance; typically, the VIG would be two panes of 3 mm glass, and a U-value of 0.8-1.0 W m-2 K-1. A primary concern of the VIG design is the ultimate strength of the units to survive thermo-mechanical loads. In this work an enhanced model of such a load scenario for a VIG configuration is outlined. The model is validated using finite element methods and is found to provide greater accuracy than that obtained from existing models. The results highlight the strong effect of the edge constraint. The model is also extended to provide stress and deflection results over the surface of the glass panes. It is a simple and speedy methods for engineers and architects to use in the design and performance validation of the VIG product.



Main benefits from convection preheating in Automotive WS/SR production


The complexity of the automotive windshields and sunroofs has been increased during last years with complex shapes and increased sizes as also with new coatings and increased screen-printed areas. These features have had challenges to uniformly heat the glass with radiation. With increased forced convection the local heat transfer differences can be smooth and the heating better controlled.

In this study, the profound reasons behind the main benefits from glass preheating by increased convection in automotive windshields / sunroof production are opened. The goal of article is to present the reasons, why glass convection preheating is important for heating control and with examples present its benefits. Study describes the main parts of the heat transfer and material behavior phenomena that take place during this process stage. In the end of the article will be the sum-up of the key results and take-aways.