Kiln & Firing
Firing and kiln in porcelain production
Porcelain is a product, which thrives into a body by merger of raw material at intense heat. This process is called firing, which can happen in different kind of kiln and manufacturing stages. Depending on manufacturing competence, country and production requirements up to 5 drying and firing processes can be used, which bring the product into the end stadium of solidness. All different firing methods, types of kilns and prostages of drying behove to the fundamental unit of hard firing, which turns ceramics into porcelain first at a temperature of 1.320 °C.
We explain here, why firing of porcelain has a great imoprtance.
The burnings make one of the most sensitives and most expensive processes, which are necessary for producing ceramic dish and porcelain. Let us describe you the firing process of porcelain with the empurpled words by Karl Leutner, (Heinrich Porzellan – Selb) from 1939.
“… After glazing follows glost firing in circular kilns, gas chambers or block kilns at temperatures between 1.320 °C and 1500 °C. In the process of glost firing we differentiate between the pre- and sharp fire. Pre fire takes about 5 to 15 hours, while the whole firing process takes around 18 to 45. Now the porcelain gets its characteristics by diverse and chemical implementations. It sinters, whitens and gets translucent, the shrinkage of the body, which already happns by drying and burning, reaches its peak with linear 10 to 17 percent, all in all first at sharp firing porcelain becomes porcelain…”
Type and number of firing processes, firing time and fuel are important for quality in the production of porcelain an deserve a detailed description and presentation, which we will offer unter “Porcelain & Firing”. Many characteristics like stability of the body, the surface hardness, the degree of whiteness and the durability and corrosion resistance of porcelain are massively influenced by kiln and firing. At least firing temperature makes the significant difference between high quality hard porcelain and cheaper ceramics. Who wants to determine quality of porcelain, should concentrate on this topic extensively.