In the selection of industrial heating equipment, flanged electric heating tubes are often evaluated according to the JB/T 2379-2016 standard "Metal Tubular Heating Elements." This standard sets clear requirements for parameters such as insulation resistance, withstand voltage strength, and power deviation, and selection personnel need to verify them in combination with medium characteristics and installation conditions.
The FJ-18 flanged electric heating tube uses a flange plate welded with multiple U-shaped or W-shaped heating elements, connected to the container flange cover by bolts, and is fully immersed in the medium or installed in a pipeline. Compared with single-head threaded heating tubes, its single-unit power can reach tens of kilowatts, with concentrated heating area, making it suitable for overall heating of large-volume tanks or storage tanks. Compared with the SRY2 ordinary tubular electric heater, the FJ-18 type adds a sealing surface and fasteners at the flange, making it convenient for use under working conditions with pressure or requiring frequent disassembly and inspection, but installation requires reserved space for removing and installing the flange cover.
For different media such as water, oil, and acid-base solutions, the FJ-18 type can adjust the surface load. For water media, 3~6W/cm² is usually used; for oils, 1.5~3W/cm²; for conditions prone to scaling, lower values are recommended. Compared with plate or shell-and-tube heat exchangers, electric heating tubes are directly immersed in the medium, and thermal efficiency is significantly affected by scale layers, so there are requirements for water hardness or the carbonization tendency of oil. During design and selection, it is necessary to calculate the cold-start current, the maximum allowable temperature of the medium, and the liquid level control in the container to avoid dry burning.
The FJ-18 flanged electric heating tube can be used with a water temperature and water level instrument or temperature control instrument to achieve interlocked control of temperature and liquid level. When the liquid level is lower than the set value or the temperature exceeds the limit, the control circuit can cut off the heating power supply to reduce the risk of dry burning. Compared with explosion-proof electric heaters, the FJ-18 type is suitable for conventional heating in non-explosion-proof areas, with a protection level generally IP54, and the junction box needs to avoid locations with accumulated liquid and splashing water. This structure supports non-standard customization, including flange specifications, tube diameter, material (such as 304, 316L, 10# steel), and unfolded length. The ordering cycle is usually 3~4 days.
