An immersion heater is an energy-efficient and cost-effective way to heat liquids and gases stored in tanks, barrels, vats, and other containers. Immersion heaters offer solutions for a wide array of heating applications, from water temperature maintenance to reaching the perfect viscosities.
How Do Immersion Heaters Work?
While the designs and advantages of immersion heaters are varying, their general function and purpose are standard. Heated electrical elements are welded to a flange or screw plug and submerged directly into buckets, tanks, and other containers of liquids or other materials for direct heating.
These submerged elements are heated electrically, which in turn increases the temperature of the liquid. Heating elements are often tubular and come in various shapes such as hairpin, U-shaped, and double-looped depending on the heating needs.
Fast and efficient heating
Immersion heaters are designed for the direct heating of water, oils, gases, solvents, viscous liquids
Immersion heaters are designed for the direct heating of water, oils, gases, solvents, viscous liquids, and many other industrial products.
Because of the direct transfer of heat from the elements to the liquid, immersion heaters are ideal for fast and efficient heating. These types of heaters are essentially 100% efficient as there is a nearly net-zero loss of heat as the elements heat the product directly while submerged.
Common Applications
Immersion heaters are used widely thanks in part to their cost effectiveness and efficiency. Whether it’s freeze protection in agriculture and water treatment or reaching the ideal viscosity for oils and waxes, many industries rely on immersion heating. Following are some common applications:
- Water:
Temperature protection can pose quite a challenge, especially during freezing winter months. Immersion heaters assist workers in making sure their project stays up and running by keeping water moving in processes that require it. Immersion heaters also offer solutions for water purification and sanitation.
Circulation heaters are an optimal solution for heated water flow. Immersion heaters are commonly used for wastewater management. Processing Magazine recommends either screw plug or flanged immersion heaters for these types of jobs.
- Viscous Liquids:
Immersion heaters can help the user reach that level and stay there, streamlining user processes
Viscosity maintenance can be challenging. For products like oil, wax, or gas, colder temperatures result in higher viscosity and slower-moving materials.
Once the user's ideal viscosity level is determined, Immersion heaters can help the user reach that level and stay there, streamlining user processes and putting user viscosity troubles to rest.
- Hazardous Chemicals:
Immersion heaters are critical for maintaining controlled temperatures of gases and other hazardous chemicals.
Explosion Proof Electric Unit Heaters below and see why they are a perfect solution for materials like gas, petroleum, sewage, and more.
Immersion Heater Types
Screw Plug Immersion Heaters:
Screw plug heaters consist of hairpin-shaped tubular electric elements welded to a threaded screw (generally 1” NPT up to 2.5” NPT) and placed directly through the tank wall or pipe coupling for heating. Screw-plug immersion heaters are ideal for small tanks requiring more precise and focused heating.
Screw plug heaters offer control by supplying a controlled temperature to users with valuable water, oil, or other liquid chemicals. Screw plug sizes range from ½” to 2 ½” and in varying watt densities to fit an array of applications.
- Common applications: Commonly used for temperature protection, process piping, industrial tanks, and barrels.
- Pros: Heating is fast and efficient, simple to use, and ideal for smaller applications or when small is limited.
- Cons: Depending on the size and wattage, a screw plug heater might not be up for the job at hand. There are many options for custom products to make sure users' heating requirements are fulfilled.
Flanged Immersion Heaters:
Flanged immersion heaters offer longevity and simplicity to user immersion heating needs
Ideal for industrial process heating, flanged immersion heaters offer electric heating elements welded to a flange (sized up to 50” NPS), which is then bolted to the wall of the tank requiring heating. For attachment, B7 studs with 2H nuts through ANSI flange connections are used to secure the heater to its mating flange.
Immersion heating is incredibly efficient as heat loss is minimized and tubular elements can reach temperatures up to 1200°F. Flanged immersion heaters offer longevity and simplicity to user immersion heating needs.
- Common applications: boilers, oil and other chemicals, industrial tanks, and other high-pressure heating applications.
- Pros: Heating is fast and efficient, and can be used in a wide variety of applications. Easy to install and long-lasting. Flanged immersion heaters offer secure placement for heavier-duty heating jobs. Downtime is minimized as cleaning and heater maintenance are simple.
- Cons: Heaters installed in a process can incur coking or scaling, requiring periodic cleanings to reduce the risk of early failure. For this preventative maintenance to be done, tanks and processes must be drained to clean or replace the heating elements. Flanged immersion heaters are often subject to poor process sensor placement. It’s critical to locate the process and over-temp sensors when using this type of heater.
Over-the-Side Heaters:
Over-the-side immersion heaters provide applicable solutions for freeze protection, water storage, maintenance of wax or viscous fluids, and other thermal heating applications.
These units can be easily mounted through the top of a tank or vessel.
- Common applications: Viscosity control, freeze protection, preheating gas and oil, and other larger heating needs. An optimal choice for many different industries.
- Pros: Over-the-side immersion heaters can be placed into larger tanks or other containers without requiring any major reconstruction or changes to infrastructure. They are versatile and economically friendly. Additionally, these heaters can be removed for cleaning without needing to empty tanks and containers.
- Cons: Because over-the-side heaters must be placed through an opening in the container, liquids are exposed to ambient conditions.