Views: 437 Author: Site Editor Publish Time: 2024-07-25 Origin: Site
Yingtai:Reasons for The Rupture of Penicillin Vials During Freeze-drying
Although rare, the rupture of penicillin vials during freeze-drying not only leads to product loss but also poses significant challenges in cleaning up shattered vials, washing and validating freeze-drying equipment. The presence of broken glass fragments poses a risk of contamination to other open vials and can potentially damage vacuum seals on drain valves, compromising equipment integrity.
Some experts attribute freeze-drying fractures to thermal stresses, suggesting that modifying the thermal properties of the vials could reduce such incidents. Today, we primarily discuss the most common form of freeze fracture, where stresses in the glass are caused by internal forces due to product expansion during freezing, rather than thermal stresses from processing temperatures.
Principle: Fractography is a common and effective method for studying the reasons behind fractures in glass products. When force acts upon a glass object, it undergoes elastic deformation (strain), resulting in compressive and tensile stresses. The distribution of these stresses within the glass depends on factors such as the container's design, thickness distribution of the glass, and the type of forces applied to the object. Glass fractures only under tensile stress, with cracks propagating perpendicular to the distribution of these stresses. Therefore, fracture patterns accurately reflect the types of forces acting on the glass object and can be used for post-analysis of glass vial ruptures.
Thus, fracture patterns and stress analysis indicate that the most common form of penicillin vial rupture is likely due to outward expansion of the product during freezing.