Overview
ISO 2747:1998 is an international standard developed by the International Organization for Standardization (ISO) that specifies a method for determining the resistance of vitreous and porcelain enamelled cooking utensils to thermal shock. Thermal shock resistance is a critical performance property for enamelled kitchenware, ensuring durability when subjected to sudden temperature changes during everyday use. This second edition, revised from the original 1973 edition, provides a standardized testing procedure that manufacturers and quality control laboratories can apply to assess enamel quality and longevity under thermal stress.
Key Topics
- Thermal Shock Test Definition: A series of operations starting with pouring cold water into a heated specimen and ending when the specimen reaches a targeted test temperature.
- Thermal Shock Temperature: The temperature to which the enamelled specimen is heated before being rapidly cooled with cold water.
- Thermal Shock Resistance: The difference between the thermal shock temperature and water temperature at which visible damage, such as chipping or tension cracks, first appears.
- Testing Procedure:
- Heating the enamelled utensil incrementally from 200 °C with a 20 °C increase after each successful test.
- Pouring cold water at 20 °C inside the hot utensil and observing for damage.
- Repeating until damage is visibly detected.
- Equipment Requirements:
- Electric hot-plate with specific diameters and power ratings to ensure consistent heating.
- Temperature measuring devices accurate to ±2 °C.
- Water receptacles, stop-watch, and drying materials.
- Sampling and Specimens: At least three representative utensils from a batch, tested without modification.
- Damage Assessment: Visual inspection at 250 mm distance or enhanced using colored penetrating fluids to detect fine cracks.
Applications
- Quality Control in Manufacturing: Ensures vitreous and porcelain enamelled cooking utensils meet durability expectations before release to market.
- Product Development: Helps manufacturers improve enamel formulations and processing methods for enhanced thermal shock resistance.
- Compliance Verification: Assists regulatory bodies and certification organizations in verifying that enamelled kitchenware complies with international safety and performance standards.
- Consumer Safety Enhancement: Reduces the risk of utensil failure due to cracking or chipping, preventing injuries and prolonging cookware life.
- Material Comparison: Enables standardized comparison of thermal shock performance across different enamel types and coatings.
Related Standards
- ISO/TC 107: Technical Committee responsible for metallic and other inorganic coatings, under which ISO 2747 falls.
- Other ISO standards related to vitreous and porcelain enamels, such as those covering coating thickness, adhesion, and chemical resistance.
- International standards involving kitchenware safety and performance, complementing thermal shock testing for comprehensive product evaluation.
- IEC standards when electrotechnical aspects of enamelled appliances are considered in broader household appliance standards.
ISO 2747:1998 provides a rigorous, well-defined testing methodology that ensures enamelled cooking utensils withstand the thermal stresses common in kitchen environments. Implementing this standard supports manufacturers and labs in delivering high-quality, reliable cookware that maintains its integrity even under rapid temperature shifts.
Open preview (PDF)Vitreous and porcelain enamels — Enamelled cooking utensils — Determination of resistance to thermal shock
