Choosing the Right Strip Heater: Mica or Ceramic?

Strip heaters are used by industry to efficiently transfer heat to a desired surface. While heating tapes and narrow silicone rubber heating blankets can be considered “strip heaters,” this article will focus on two styles of ridged, flat strip heaters that include metal sheaths, resistance heating elements, and a ceramic material for insulation. The heating industry groups these as either Mica or Ceramic heaters based on their insulating material.

Strip heaters are designed to provide uniform heat distribution, making them ideal for processes that require precise temperature control. They are very efficient in doing so because they are designed to have the entire heater in direct contact with the flat surface being heated. In some applications, heaters can be sandwiched in between two flat surfaces reducing the heat loss from the “cold” surface exposed to the environment.

Mica Strip Heaters

1. Food Processing: Mica strip heaters are also used in food processing equipment such as food warmers, hot plates, and ovens. Heat is efficiently transferred from the strip heater to walls, shelves, and steam tables. They are regulated to provide enough heat to keep food at the desired temperature, with the goal of maintaining quality.
2. Plastic Processing: Mica strip heaters are widely used in plastic processing industries. They can be used in plastic extruders, injection molding, plastic bending and forming presses. Temperature uniformity is critical to ensure stresses are not created in the finished product that could impact quality.
3. Packaging and Sealing: Mica strip heaters are used in sealing machines to provide consistent heat for sealing plastic films and other materials. They may also be used in blow molding machines that are used to manufacture the film used in packaging.
4. Medical Equipment: Medical equipment such as incubators and sterilizers utilize strip heaters for laboratory testing, eliminating bacteria on medical instruments, and even blanket warming.                     

Ceramic Strip Heaters

1. Heat Treating: Ceramic strip heaters are commonly used in heat treating applications as they can reach higher temperatures than mica heaters. They provide the high temperatures required for processes such as annealing, tempering, and hardening of metals. Uniform heating is required as it impacts the grain structure of the metals as they heat and cool.
2. Drying and Curing: In industries such as printing and painting, ceramic strip heaters are used for drying and curing applications. Ceramic heaters can be manufactured with fins that are used to heat air for these processes.
3. Laboratory Equipment: Like mica heaters, ceramic strip heaters are used in various laboratory equipment such as ovens, incubators, and hot plates.
4. Semiconductor Manufacturing: In the semiconductor industry, ceramic strip heaters are used in processes such as wafer processing and testing. They provide the necessary heat to ensure the proper functioning of the equipment and the quality of the semiconductor products.
5. Forming & Fabricating: Ceramic strip heaters can be used in manufacturing applications to clean parts after machining. Often parts have residual oils the must be cleaned in heated water baths utilizing ceramic heaters.

In many applications, either a mica or ceramic heater can be used, so how do you decide. The chart below illustrates some of the distinguishing characteristics of these two types of heaters. In most cases, ceramic heaters are capable of higher temperatures; however, most manufacturers have only one or several fixed widths. Mica heaters can be manufactured to exact widths required for the process and are more easily customizable to add slots, terminals, holes and notches. Ceramic strip heaters have the advantage of providing more heat because they are capable of 75-120 watts per square inch compared to 40 watts per square inch for mica.

Both mica and ceramic strip heaters play a crucial role in various industrial applications. Their ability to provide uniform and precise heating makes them indispensable in industries such as plastic processing, packaging, food processing, medical equipment, heat treating, drying and curing, laboratory equipment, semiconductor manufacturing, and general manufacturing. BriskHeat can provide both mica and ceramic strip heaters operating at voltages up to 480 VAC in two weeks or less. Contact your BriskHeat Account Executive or Authorized Distributor for additional information.