Glass-lined steel

Industrial porcelain enamel (also known as glass lining, glass-lined steel, or glass fused to steel) is the use of porcelain enamel (also known as vitreous enamel) for industrial, rather than artistic, applications. Porcelain enamel, a thin layer of ceramic or glass applied to a substrate of metal, is used to protect surfaces from chemical attack and physical damage, modify the structural characteristics of the substrate, and improve the appearance of the product.

Enamel has been used for art and decoration since the period of Ancient Egypt, and for industry since the Industrial Revolution. It is most commonly used in the production of cookware, home appliances, bathroom fixtures, water heaters, and scientific laboratory equipment.

The most important characteristic of porcelain enamel, from an industrial perspective, is its resistance to corrosion.Mild steel is used in almost every industry and a huge array of products; porcelain enamel is a very economic way of protecting this, and other chemically vulnerable materials, from corrosion. It can also produce very smooth, glossy finishes in a wide array of colours; these colours will not fade on exposure to UV light, as paint will. Being a fired ceramic, porcelain enamel is also highly heat-resistant; this allows it to be used in high-temperature applications where an organic anti-corrosion coating or galvanization may be impractical or even dangerous (see Metal fume fever).

Porcelain enamel also sees less frequent employment of some of its other properties; examples are its abrasion resistance, where it may perform better than many metals; its resistance to organic solvents, where it is entirely impervious; its resistance to thermal shock, where it can resist rapid cooling from temperatures 500°C and higher; and its longevity.

Porcelain enamel is used most often in the manufacture of products that will be expected to come under regular chemical attack or high heat such as cookware, burners, and laboratory equipment. It is used in the production of many household goods and appliances, especially those used in the kitchen or bathroom area: pots, pans, cooktops, appliances, sinks, toilets, bathtubs, even walls, counters, and other surfaces.

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