Immersion heaters have a variety of applications in the chemical process industries. Knowing which heaters to specify and how to install them can make a manufacturing process more cost-efficient. Its time to learn about immersion heater types; typical applications; and selecting, sizing, specifying, installing and using the heater.
Electric process heaters use electricity to increase the temperature of liquids and gases within process systems. Depending on the application, electric process heaters may be used for both direct and indirect heating, which makes them a particularly versatile heating option. To help you find the best electric heater for your needs, we have compiled a concise summary of electric process heater systems and their common uses.
What is a heating element?
Heating elements are typically either nickel-based or iron-based. The nickel-based ones are usually nichrome, an alloy (a mixture of metals and sometimes other chemical elements) that consists of about 80 percent nickel and 20 percent chromium (other compositions of nichrome are available, but the 80–20 mix is the most common). There are various good reasons why nichrome is the most popular material for heating elements: it has a high melting point (about 1400°C or 2550°F), doesn't oxidize (even at high temperatures), doesn't expand too much when it heats up, and has a reasonable (not too low, not too high, and reasonably constant) resistance (it increases only by about 10 percent between room temperature and its maximum operating temperature).
In water heaters, the nichrome element is covered with an outer sheath made of stainless steel, tin-coated copper, or INCOLOY? (an iron-nickel-chromium "superalloy," which is rustproof, long-lasting, and works well in hard-water areas). The sheath is insulated from the heating element by magnesium oxide, an unusual material that's a good heat conductor but a poor electrical conductor, so it allows heat to flow from the nichrome but not electricity.Immersion heaters have a variety of applications in the chemical process industries. Knowing which heaters to specify and how to install them can make a manufacturing process more cost-efficient. Its time to learn about immersion heater types; typical applications; and selecting, sizing, specifying, installing and using the heater.
Immersion heaters, as the name implies, are immersed in water, oils, solvents, process solutions, molten materials and gases, where they release all their heat within the fluid, which makes them nearly 100% energy-efficient. Immersion heaters are offered in a wide variety of sizes, kilowatt ratings, voltages, terminations, sheath materials and accessories. They are often custom engineered for a specific application.
The basic immersion heater configurations are the screw plug, flange, pipe insert or bayonet, circulation or in-line, booster, and of an over-the-side style. They?re usually available in a round tubular design or a flat tubular design. The flat variety can operate at a higher watt density without overheating the sheath. Heaters also are grouped into two categories ? pressurized (closed) systems and non-pressurized (open tank) systems.
Understanding Electric Process Heaters
Electric process heaters use electricity to increase the temperature of liquids and gases within process systems. Depending on the application, electric process heaters may be used for both direct and indirect heating, which makes them a particularly versatile heating option. To help you find the best electric heater for your needs, we have compiled a concise summary of electric process heater systems and their common uses.
What is a heating element?
Heating elements are typically either nickel-based or iron-based. The nickel-based ones are usually nichrome, an alloy (a mixture of metals and sometimes other chemical elements) that consists of about 80 percent nickel and 20 percent chromium (other compositions of nichrome are available, but the 80–20 mix is the most common). There are various good reasons why nichrome is the most popular material for heating elements: it has a high melting point (about 1400°C or 2550°F), doesn't oxidize (even at high temperatures), doesn't expand too much when it heats up, and has a reasonable (not too low, not too high, and reasonably constant) resistance (it increases only by about 10 percent between room temperature and its maximum operating temperature).
In water heaters, the nichrome element is covered with an outer sheath made of stainless steel, tin-coated copper, or INCOLOY? (an iron-nickel-chromium "superalloy," which is rustproof, long-lasting, and works well in hard-water areas). The sheath is insulated from the heating element by magnesium oxide, an unusual material that's a good heat conductor but a poor electrical conductor, so it allows heat to flow from the nichrome but not electricity.