The pyrometric cone is a ceramic device used to measure the temperature inside a kiln during firing. These cones are made of special ceramic materials that deform or bend at a specific temperature, providing a visual way to check if the kiln has reached the desired temperature for the maturation of the clay or glaze.
Unlike traditional thermometers, pyrometric cones not only measure temperature, but also capture the combined effect of heat and heat exposure time, which is critical for proper maturation of the material. This allows a more accurate measurement of the vitrification process or maturity of the ceramic piece.
Pyrometric cones are essential in firing processes where temperature accuracy is critical, such as in stoneware or porcelain ceramics, where a small variation in temperature or exposure time can affect the quality of the final finish, vitrification or glaze appearance. These cones are numbered according to the temperature range they reach, with values ranging from low temperatures (such as cone 06, for low-temperature ceramics) to high temperatures (such as cone 10, for high-temperature porcelain or stoneware). Each number corresponds to a specific melting point, facilitating precise control during firing.
Interesting Fact
Pyrometric cones were developed in the late 19th century as a more accurate way to measure temperature in kilns, as thermometers of the time were unreliable at such high temperatures.
Helpful Tip
Place several cones of different ranges in the kiln so that you can monitor the firing progress more accurately. This will also allow you to evaluate the temperature uniformity in different parts of the kiln.
