The edge sealing process during the manufacturing of a vacuum glass panel needs to be highly reliable in order to maintain the vacuum state of the panel and hence, it is researched extensively. In this paper, a hydrogen mixed gas torch was used to seal glass edges by melting the glass edges. When the glass edges are sealed by using the hydrogen mixed gas torch, the process conditions determine the edge sealing shape, which affects the strength and heat transfer properties of the glass panel.
When the glass edges are sealed by the hydrogen mixed gas torch, the factors that affect the joint shape were selected and set as four process parameters, and three geometrical parameters were selected to represent the shape of edge. Using the experimental design, the edge sealing experiments were performed using a written test condition table according to the levels of the set process parameters and the correlation between the process parameters and geometrical parameters was studied using various statistical methods. The derived non-linear regression equation and the analysis of variance were used to validate the regression, and a sensitivity analysis of the derived regression according to the process parameters was performed. In addition, considering the main effect plot and the interaction plot of the process parameters, the effect of the process parameters on the shape was analyzed.
To analyze the strength properties along the sealing shape, an edge sealing experiment was followed by the four-point bending strength test. To characterize the strengths of the various shapes, Weibull distribution was used to estimate the shape parameter and the scale parameter, followed by the statistical breakage strength property analysis. Furthermore, the shape parameter values that satisfy the fracture strength were derived by considering the characteristic strength and the safety factor.
In order to study the thermal conduction according to the various shapes of the edge joints, the junction geometry was modeled and a numerical analysis was performed. To study the heat conductivity of various shapes, a response surface analysis method called Box-Behnken design was used to model the joint geometry. The model was analyzed under the ASTM winter conditions. Based on the results, the optimum shape parameter value that minimizes the temperature variations in the edge part was derived.
Glass edges can be melt-sealed by using a hydrogen mixed gas torch into a shape that satisfies the strength and heat transfer properties of the edges by using the analyzed result of the correlation between the process parameters and geometrical parameters.