Vitreous Enamelling - The Process
Vitreous enamel is a type of glass which is used as a decorative or engineering finish on metal.
Vitreous enamel has all of the properties associated with glass – hardness, scratch and graffiti resistance, colour stability, and fire resistance.
* Please Note: This is NOT a resurfacing service.
Firstly the bath is shot blasted to remove all of the original enamel. This process varies in the amount of time it takes to complete due to the size of the bath and thickness of the enamel.
The bath is then ground coated (this is like an undercoat which is sprayed on to the bath and force dried) before being put in the furnace for the first of approximately four firings at a temperature in excess of 800 degrees celsius.
After 45-60 minutes the bath is taken out of the furnace and allowed to cool. It is then stoned down to smooth the surface of the newly fired ground coat so it is ready for its first of approximately four applications of the vitreous enamel cover coat (this is the actual enamel that when fired in the furnace gives you the white shiny surface).
Sometimes the baths don’t always appear to the standard we would expect the first time around. A bath can be taken out of the furnace for the last time after having had all of the previous stages successfully completed and there can be a problem. The problem could be excessive contamination from the cast iron, or boiling (this is when any given area of the vitreous enamel can appear to look like bubbling hot soup for want of a better description). Or indeed an area of the enamel has lifted (this means due to an area of the bath being particularly rusty in its prior state, despite shot blasting etc. the rust has penetrated deep into the cast and with the extreme temperatures has been drawn to the surface again and pushes the enamel off the cast iron).
When the above problems do occur this may mean a slight delay for the customer because we have to start the whole process again from the beginning. After repeating the vitreous enamelling process there may be still slight imperfections due to the nature of the process. Please refer to Finished Result section in our Standard Trading Conditions.