Screw plug heaters
Screw plug heaters are submersible heating elements that go directly into the tank or vessel. They deliver a direct transfer of heat, which allows liquids to heat up rapidly. Screw plug heaters contain hairpin tubular elements that are either brazed or welded into a pipe thread fitting. Screw plug heaters are ideal for smaller containers and vessels.
Over-the-side heaters
Over-the-side heaters are a type of immersion heater designed for installation outside of a tank or vessel. Usually, they are installed in the upper portion of the vessel, with brackets fastening the heater onto the tank wall. Over-the-side heaters often use copper, steel, cast alloy or titanium in their heating elements. Due to the mobility of these heaters, project managers often use them for multiple vessels (and applications).
Flanged heaters
Flanged heaters act as a source of direct heat to a liquid medium. They typically use hairpin elements or tubular bugle elements that extend from the flange’s face. These heaters usually contain thermowells that allow for the use of temperature reading devices such as thermocouples and thermostats to provide better temperature control. These devices also have limit sensors to prevent overheating and damaging heater elements.
Circulation heaters
Circulation heaters have a wide range of applications, making them a highly-prized type of industrial heater. The target fluid enters through an inlet that’s closest to the heater. The heater then applies heat to the liquid as it flows within a vessel. The fluid then exits the outlet and circulates through a piping circuit. How these heaters function within specific industrial applications can vary slightly.
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