If you’re stuck trying to decide between a mica band heater and a ceramic band heater, there are several things you should consider before making your decision. There are significant differences between the two types of band heaters, including customization, temperature capacity, and watt densities, just to name a few.
In this article, we’ll walk you through the differences between mica band heaters and ceramic band heaters to help you decide which one you should use for your heating application.
Ceramic band heaters can withstand a higher temperature than mica band heaters. Ceramic band heaters can operate at a maximum temperature of 1200º F, while a mica band heater can operate at a maximum temperature of 800º F.
Heater Life Expectancy
Typically, ceramic band heaters will have a longer life expectancy due to the coiled resistance wire that is fed through ceramic blocks, also known as knuckles. Mica band heaters use thin resistance ribbons. The coiled resistance wire has a smaller ratio of surface area to internal cross-sectional area. Therefore, it doesn’t oxidize and burn through as fast as the ribbon.
When it comes to watt density, mica band heaters have a higher density than ceramic band heaters. Because the resistance ribbon in a mica band heater is tightly clamped between pieces of mica, there is better heat transfer from the ribbon to the exterior surfaces of the heater. Also, mica band heaters generally will have less heated area than a ceramic band heater – especially in smaller band heaters.
Customizability plays a big factor in the differences between mica and ceramic band heaters. Mica sheets can be cut into customized shapes and sizes, whereas ceramic band heaters are limited by the size of the knuckles. Mica band heaters are also much more customizable when it comes to dimensions. Ceramic band heaters are limited to ½” width increments, whereas mica band heaters can be any width within the upper and lower limits of at least 1” by 1”, depending on the specific mica band configuration.
Ceramic band heaters are more expensive than mica bands. This is because ceramic knuckles are quite expensive when compared to the thin sheets of mica that mica bands are constructed from. The expense of the ceramic band heater is compensated for by the increased efficiency compared to mica band heaters.
Standard ceramic band heaters have one layer of ⅜” thick ceramic paper insulation over the knuckles and a stainless-steel outer sheath that reflects heat back into the process. The “heat saver” ceramic band insulation option has one layer of ⅛” thick ceramic paper topped with a reflective stainless-steel sheath, and an additional 2 layers of ⅜” thick paper, topped by an additional sheath.
All of this insulation yields a higher efficiency heater in ceramic bands in comparison to a mica band heater. Ceramic band heaters also offer a “vented outer sheath” option. Allowing heat to escape from the process, if needed, for your application.
In conclusion, the main differences between a mica band heater and a ceramic band heater are that mica bands are cheaper, can have higher watt density, and are more easily customizable, whereas ceramic bands are more efficient, can withstand higher temperatures, and generally last longer. When deciding between a mica band heater or a ceramic band heater, it ultimately comes down to examining your heating process and your specific needs for a band heater.
If you have any further questions about band heaters or need assistance, please contact our engineers at Thermal Corporation.