The Relationship Between Dishwasher Working Principle and Glass Wear
Dishwashers clean dishes through the combined action of high-temperature water (typically 60-70℃), high-pressure spray arms, and alkaline detergent.
These factors affect the glass as follows:
High-Temperature Softening of the Glass Surface: At high temperatures, the microstructure of glass softens, especially common soda-lime glass (common in inexpensive cups), which has poor heat resistance (approximately 80-120℃). Prolonged high-temperature washing may cause micro-cracks on the surface to expand.
Chemical Corrosion by Alkaline Detergents: Dishwasher detergents typically have a pH of 11-12. This highly alkaline environment reacts slowly with the silica in the glass, causing the surface to lose its shine.
Mechanical Friction Damage: The spray water pressure can reach 20-40 kPa (refer to GB/T 20290-2016 standard). The high-speed water flow carrying food residue repeatedly impacts the glass surface, creating an effect similar to "sandpaper polishing."
Practical Tips to Reduce Glass Wear
Choose the appropriate program: Use the "Gentle Wash" or "Glass-Specific" mode (water temperature ≤45℃, water pressure reduced by 30%).
Placement Tips: Avoid placing glassware directly against metal tableware to prevent collisions; place them upside down to reduce direct water impact on the inner wall.
Auxiliary Protection: Add a special glass protectant (containing silicate components) to form a temporary protective film on the surface.
Long-Term Effects and Scientific Testing
Laboratory tests (2022 experiment by the China National Light Industry Council) show that after 200 machine washes of ordinary glass:
Light transmittance decreases by 8%-12% (spectrophotometer measurement)
Surface roughness increases by 3 times (atomic force microscopy observation)
It is recommended to hand wash high-value glassware regularly, or choose heat-resistant glass products labeled "dishwasher safe".