What Is a Rod Heater? 

rod heaters

A rod heater is a cylindrical heating component used in high-temperature industrial applications, including tempering, hardening and baking. Rod elements are also commonly used in radiation, convection and conduction heating applications. These heaters work by converting electrical energy into heat. They can vary considerably in size and form, but all are designed to function at high temperatures.

Rod heaters are typically mounted on doors, floors and walls. Most floor components are situated on piers, allowing for debris to be trapped underneath the element. Other heating components are located on terminal clamps to accommodate additional features.

What Are the Benefits of Rod Heating Elements?

There are many benefits of using rod heating elements in industrial heating applications. First, rod heaters are highly efficient and generate heat very quickly. While other heating elements can take several minutes to heat up, rod heaters are ready to use in about two minutes. Second, rod heaters are durable and can be used in a wide variety of harsh environments.

How Does a Heating Element Work?

Heating elements transform electricity into heat by using a resistor to convert electrical energy into heat energy. In other words, heating elements become hot when electricity flows through them. However, other components besides resistors conduct energy. Many materials, even a piece of wire, can generate heat if it encounters electricity. Thus, heating elements made from various materials provide a reliable heat source when electric current flows through it.

When you need a high-temperature, concentrated heat source to temper a die block or maintain a workable glue temperature, you are looking for a cartridge heater. Also called insertion heaters, these versatile gems have endless production and manufacturing uses.

Hi-Watt Inc. is a leading distributor of industrial heaters, and we can help you find the perfect cartridge heaters and configuration for your unique application.

Common Applications for Cartridge Heaters

Hi-Watt offers a diverse range of industrial cylindrical heating units. From packaging and food production to medicine and engineering, these power-packed heating products are designed to apply consistent, concentrated heat to solids, liquids or gases. The uses for these heaters span dozens of manufacturing and processing sectors. Some of the most common uses for rod heaters include:

  • Heating metal components, such as intricate injection molds or die blocks
  • Helping maintain optimum working temperatures by heating applicators of glue and sealant products
  • Preventing condensation in closed circuits and control panels
  • Maintaining temperatures for engine sump oil and other liquids, such as water or chemical solutions.

Cartridge-based heating products are available in a range of temperature options and watt densities, depending on the application. Despite the high-heat capability of some units, this class of heaters is uniquely energy efficient.

Cartridge Heaters

What Are Cartridge, Immersion and Tubular Heaters?

Other than rod heaters, several different types of heaters generate heat in industrial applications. Many people get these heaters mixed up, but it is essential to understand the differences.

  • Cartridge heaters: Referring to a family of heaters, cartridge heaters have an internal heating mechanism that can be inserted into a unit wall to transfer heat to another object. Typically, cartridge heaters are inserted into a container to warm the materials inside the object. An example of a cartridge heater is an extrusion line the warms the oil inside an engine.
  • Tubular heater Tubular heaters are used to heat an object evenly on all sides. Tubular heaters evenly disbursed heat, meaning no corners or areas generate more heat than other areas. These heaters are often inserted into containers to maintain consistent temperature across the entire object. They usually have a high watt density per square inch, allowing for more heat to be emitted in less time.
  • Immersion heaters: An immersion heater is named after its most common application. These heaters are commonly inserted through a component wall into a liquid or other material to be heated. Immersion heaters are an example of the heating elements used in water heaters. These heaters are used in dozens of industrial applications including construction, manufacturing, aeronautics and automation.

This is not a comprehensive list of heating elements. Other types are used in additional applications.

What Is a WATROD Tubular Heater?

A WATROD tubular heater comes in single and double-ended termination iterations. The single-ended heater has two terminals at one end of the device. The opposite end is sealed shut. On the other hand, double-ended tubular heaters are highly adaptable and used in applications requiring flexibility. These heaters come in various styles, with some designed with multiple resistors coils and others made with thermocouples inside a sheath housing.

The advantage of using a double-ended type is it can accurately determine a device’s internal temperature. Single and double-ended tubular heaters are used in a wide range of air and immersion heating applications.

Rod Type Heaters Available

Heating processes, in general, consume high levels of energy. Rod heaters are designed to transfer heat to the target with nominal heat loss. On an industrial scale, lower energy consumption means significantly lower production costs. Hi-Watt offers four types of these energy-efficient heaters.

Insertion Heaters

Our standard insertion heaters are chosen with efficiency, value and durability in mind. Used for heating metal from the inside out, the unit inserts snugly into a specially drilled cylinder. A nickel-chromium resistance wire ensures maximum longevity, and a stainless-steel sheath encases the heating element to retard oxidation.

Heat travels through sturdy lead wires that attach to the end of the rod heaters. The lead wires are capable of temperatures up to 550 degrees Celsius. As the heat moves from the lead wires through the heating coil, the steel sheath heats up. That heat then transfers out to the target material.

Immersion Heaters

Immersion units are designed to be placed directly into liquids, such as water, oil or other solutions. Immersion heaters or immersion heaters for water, have diverse applications, and come in flanged, screw-plug, and over-the-side configurations.

Split-Sheath Heaters

This specialized design provides insertion heaters with some useful advantages. The heating coil passes through two half-circle sheaths that fit together to form a circle. When heated, the sheath expands to contact the surrounding material. Split-sheath rod heaters facilitate maximum heat transfer and allow for easy removal of the unit from the hole.

Custom Cartridge Heaters

Our line of insertion and immersion heaters are available in selection of metric and imperial dimensions, temperature ranges and watt densities. If your application requires something outside of our standard line, we can provide custom options that conform to the dimensions and wiring configuration you need.

The Hi-Watt Difference

Hi-Watt’s mission is to provide superior products and excellent customer service. We back every product we sell with US-based customer support.  Hi-Watt is more than a distributor of rod heaters; we are a partner to our clients in the thermal industry – always here to help with replacement parts, system modifications and design services.

When your operation calls for a powerful, concentrated heat source, you will likely be shopping for insertion heating products. Hi-Watt Inc. is here to help you find the best solution for your sector’s unique heating needs.

Whether you need an immersion heater for an engine sump or a split-sheath unit for use in a safety block, we’ve got you covered. We look forward to working with you to find the unique heating solutions that help make your operation the best it can be.