A band heater is a useful item for a variety of different industrial applications, but they’re mainly used to indirectly (and externally) heat pipes and tubes.
In this article, we’ll cover how these heaters work, the different types, and how to test them.
Let’s start by explaining what a band heater is.
What Are Band Heaters?
Band heaters are ring-shaped devices that clamp around and externally heat cylindrical surfaces. All these heaters use electrical conduction, although some types may use a combination of electrical conduction and radiation. Most heaters are made with metals because they are exceptional conductors. The three main types of band heaters are mica, mineral-insulated, and ceramic, which we’ll discuss in detail in the next section.
Types of Band Heaters
As previously mentioned, the three primary types of band heaters are ceramic, mineral-insulated, and mica. You can also divide them up further by using factors like installation, mounting, dimensions, termination type, sheath material or sleeve, and performance specifications.
Mica Band Heaters
Mica heaters feature mica, which is a group of minerals. Wrapped around the mica core are wires. Together, the core and wires are bent into a band. Mica heaters have a lower maximum temperature of around 900 degrees Fahrenheit, but their resistance to water and chemicals means they are a popular choice for harsher operating environments.
Mineral-Insulated Band Heaters
Like the name suggests, this type of band heater is made with mineral insulation that has higher thermal conductivity than mica and ceramic. It’s the perfect solution when you need the highest maximum temperature possible, as they can reach temperatures up to 2,000 degrees Fahrenheit. They also provide more efficient heat transfers.
Ceramic Band Heaters
Ceramic heaters feature inner resistance coils that are spirally wound and threaded through insulated ceramic tiles. This type of heater uses conduction and radiation to externally heat cylindrical elements. The main advantage of a ceramic heater is that they can decrease energy consumption and overall operations costs. They typically have a maximum temperature of approximately 1,400 degrees Fahrenheit.
How Do Heating Bands Work?
As we covered before, band heaters mainly use electrical conduction to heat up elements. Heating bands are metal filaments that have a protective covering encasing them and that protective covering turns electricity into heat. After that, the heating band will transfer the heat energy via a controlled method to another object. The heating band will do this via either conduction.
How Do You Test a Band Heater?
To ensure optimal performance, you should always test your band heater before you install it. If your heater is already installed, but you’re not sure whether it’s performing optimally, a test will help you better understand the answer. For safe testing and less downtime, we recommend the following steps:
- Turn off the power going to the heater.
- Disconnect the heater’s lead wires.
- After that, you must locate the number that is engraved on your heater; this number specifies the voltage and wattage.
- The next step is for you to measure the resistance between the two post terminals or the two lead wires. It depends on the type of heater that you have. The heater’s resistance should be approximately the heater’s voltage squared divided by the heater’s wattage; the formula for this is R = V2 / W.
- After you have the total resistance number (measured in ohms), you’ll want to then perform another test using an ohmmeter.
The standard tolerances are as follows: if your heater is operating at room temperature, the resistance measured by the ohmmeter can be 10% less or 5% greater than the total you calculated using the formula above. If the resistance value falls outside of this range, your heater is not operating as it should be.
Always consult your specific heater manufacturer’s installation and operation manual for best practice and maintenance procedures. All electrical wiring should be done by a qualified electrician.
Want to Learn More About Band Heaters? Contact Hi-Watt Today!
Hi-Watt is a leading supplier of band heaters and other industrial heating solutions. You can view additional information here. If you have questions about our band heaters or want to request a quote, please fill out our convenient online form.