Highly Polished Amber Colored Glass Tube Small Test Tube 1-20ml

Highly polished Neutral Glass Tube

Heat-resistant glass (refers to a special glass that contains boric acid and silicic acid with strong heat resistance and can withstand changes in temperature difference between cold and heat It is not easy to break. It has a series of excellent properties such as low expansion, thermal shock resistance, high temperature resistance, corrosion resistance, and high strength. Its raw material price is higher than ordinary glass, and the manufacturing cost is also higher. Therefore, the selling price of heat-resistant glass is higher than that of ordinary glass and tempered glass. The glass is high. The heat-resistant glass material has a high safety factor and will never self-explode like tempered glass; the coefficient of thermal expansion is small, the range of resistance to rapid temperature changes (≥120°C) is large, and the maximum temperature of heat resistance is up to 1200°C. Heat-resistant glass Mostly used for utensils, baby bottles, experimental beakers, industrial boiler sight glasses, mechanical equipment window glass, etc.

The purpose is to eliminate permanent stress and structural imbalance in glass products. Glass is a poor thermal conductor. After the product is formed, the surface layer and the inner layer will have a temperature difference during the cooling process. When the surface layer is solidified and the inner layer is viscous, the temperature difference exists but the stress relaxation does not exist. This temperature difference occurs when the surface layer is cooled to room temperature. , The inner layer continues to cool down and shrinks, which is hindered by the surface layer to produce tensile stress, and at the same time, the surface layer produces compressive stress, which is permanent.