An Overview of Flanged Electric Heaters:
Flanged electric heaters, also known as flanged electric heater tubes, flanged heaters, flanged electric heaters, threaded flange electric heaters, flanged heaters, immersion electric heaters, and more, are essential components of fluid heaters such as gas heaters (e.g., air heaters, nitrogen heaters, hydrogen gas heaters), liquid heaters (e.g., electrically heated thermal oil furnaces, industrial pure water heaters, electric hot water boilers, heavy oil heaters), and other types of heating systems.
Flanged electric heaters utilize U-shaped tubular electric heating elements. Designed according to specifications for heating different media, they are mounted on the flange cover according to power configuration requirements and inserted into the material to be heated. As the heating element operates, it emits a large amount of heat that is transferred to the heated medium, raising its temperature to meet the required process standards. Once the medium temperature reaches the set value required by the process, the control system adjusts the output power of the electric heater based on the temperature sensor signal after PID calculation, thereby controlling the resistive load of the heating element to ensure uniform temperature of the medium and meet the required specifications. In case the heating element overheats or the liquid level is too low, the interlock protection device of the heating element immediately cuts off the heating power to prevent the heating element from being damaged, thus extending its service life.
Section 2: Features of Flanged Electric Heaters:
1. Utilizing SUS304 stainless steel seamless tubes, imported European and American grade heating wire, and magnesium oxide powder.
2. High working temperature up to 850 degrees, utilizing a PID control system based on temperature sensor signals to adjust the electric heater's output power after computation, achieving temperature control for the resistive load of the heating elements.
3. The heater boasts an efficiency of over 95%.
4. Durable and long-lasting, with a lifespan of up to ten years. The interlock protection device immediately cuts off the heating power source when there is an over-temperature or low liquid level, preventing the heating element from burning out.
5. Shape and power are customizable.
6. Connection methods available include flange or threaded face sealing.
Section 3: Application of Flanged Electric Heaters:
Flanged electric heaters are widely applicable for heating water, oil, air, nitrate salt solutions, acid solutions, alkali solutions, and low-melting-point metals (aluminum, zinc, tin, bismuth alloys, etc.).
a pipeline heater: Mainly used in the blowing pipe of air heating systems for blowing hot air. Also serves as heating elements for various ovens and electric furnaces.
Boric salt solution, oil, and water heating: Consists of a curved and shaped tubular electrical heating element welded onto a flange. Used for heating in open and closed-type solution tanks and circulating systems.
Single-end heater: Designed for heating mediums that cannot be wired at both ends, suitable for use in equipment such as hot box cores, injection molding machines, molds, etc.
Section 4: Selection of Flanged Electric Heaters
Flange
Material: Carbon Steel, Stainless Steel
Sizes: 3", 5", 6", 8", 10", 12", 14", 16", 18" or larger
Pressure Rating: 150, 300 lb ANSI B16.5/HG20592-97
2. Heating Element
Material: Carbon Steel, Stainless Steel, and INCOLOY
Power Density: 1, 2.3, 3.5, 7, 11 W/cm²
Pipe Diameter: 8, 10, 12, 16, 20mm. Standard diameter is 12mm.
3. Others
The junction box features a heat dissipation area at high temperatures.
Working Voltage: 0-690V
4. Junction box
Moisture-proof
Explosion-proof and moisture-proof
5. Selection Guidance
Based on the process conditions, determine the parameters of the heater (refer to the table below), such as: the material and power density of the heater flange and electrical heating elements.
A sound choice not only saves costs economically but also extends the lifespan of the heater in use.
The following are some guidelines provided to facilitate users in selecting heaters; however, the final confirmation requires the extensive experience of engineers and rigorous calculations.
The selection of heaters is determined by the following factors:
1. Density, viscosity, specific heat, and corrosiveness of the heated medium.
2. The polluting nature of the heating element to the medium
3. Corrosion and antioxidant properties of the heating element sheath
4. Power density on the surface of the heating element, i.e., the power per unit area.
5. The high surface temperature of the heating element, determined by items 1 to 4.
Application | 1 | 2 | 3 | 4 | 5 |
Medium | pH Level | Pipe material | Power density | Recommended High | |
Or in the form of heat treatment | (Concentration %) | (W/cm2) | Surface Temperature: °C | ||
Water | Clear Water | PH6~Ph8 | Copper | 7.00 | 180 |
Process water | PH5~Ph9 | Passivated stainless steel | 7.00 | 650 | |
Weak Acid-Base Solution | 5~6% | INCOLOY | 7.00 | 870 | |
Soft water | INCOLOY | 7.00 | 870 | ||
Corrosive | Corrosive solution | 5~15% | Stainless Steel | 3.50 | 650 |
Medium corrosive solution | 10~25% | INCOLOY | 3.50 | 650 | |
Highly corrosive solutions | 30~60% | INCOLOY Stainless Steel Flange | 2.30 | 870 | |
Specialty Water | Steam Boiler | INCOLOY/Copper | 870 | ||
Oil | Low viscosity oil | Carbon Steel | 3.50 | 400 | |
Medium viscosity oil | Carbon Steel | 2.30 | 400 | ||
High-viscosity oil | Carbon Steel | 1.00 | 400 | ||
Storage oil | Lubricating oil | Carbon Steel | 2.30 | 400 | |
Air, gases, and steam | Low-temperature | Stainless Steel | 3.50 | 650 | |
High Temperature | INCOLOY | 3.50 | 870 |
Five, Flanged electric heater specifications and models:
Model Meaning:
SWDL-FL-A-B
SWDL - Company ID
FL - Flanged
A- Flange diameters of 3", 5", 6", 8", 10" and larger
B-Power
Model | Immersion Length | Power (kW) | ||||
L(mm) | 1W/cm2 | 2.3W/cm2 | 3.5W/cm2 | 7W/cm2 | 11W/cm2 | |
3″ (DN80) Flange, 3 heating elements | ||||||
SWDL-FL-3- | 600 | 1.1 | 2.5 | 3.9 | 8 | 12 |
SWDL-FL-3- | 1000 | 2.0 | 4.6 | 7 | 14 | 22 |
SWDL-FL-3- | 1500 | 3 | 7 | 11 | 21 | 33 |
5″ (DN125) Flange, 6 electric heating elements | ||||||
SWDL-FL-5- | 600 | 2.2 | 5 | 8 | 15 | 24 |
SWDL-FL-5- | 1000 | 4 | 9 | 14 | 28 | 44 |
SWDL-FL-5- | 1500 | 6 | 14 | 21 | 42 | 66 |
SWDL-FL-5- | 2000 | 8.4 | 19 | 29 | 59 | 93 |
6" (DN150) Flange, 12 heating elements | ||||||
SWDL-FL-6- | 600 | 4.4 | 10 | 16 | 31 | 48 |
SWDL-FL-6- | 1000 | 8 | 18 | 28 | 56 | 88 |
SWDL-FL-6- | 1500 | 12 | 28 | 42 | 84 | 132 |
SWDL-FL-6- | 2000 | 17 | 39 | 60 | 120 | 187 |
SWDL-FL-6- | 2500 | 22 | 51 | 77 | 154 | 242 |
8" (DN200) Flange, 18 electric heating elements | ||||||
SWDL-FL-8- | 600 | 6.1 | 14 | 21 | 43 | 67 |
SWDL-FL-8- | 1000 | 12 | 28 | 42 | 84 | 132 |
SWDL-FL-8- | 1500 | 18 | 42 | 63 | 126 | 198 |
SWDL-FL-8- | 2000 | 25 | 57 | 88 | 175 | 275 |
SWDL-FL-8- | 2500 | 32 | 73 | 112 | 224 | 352 |
SWDL-FL-8- | 3000 | 39 | 87 | 136 | 273 | 429 |
10" (DN250) Flange, 27 electric heating elements | ||||||
SWDL-FL-10- | 1000 | 17 | 39 | 60 | 119 | 187 |
SWDL-FL-10- | 1500 | 27 | 62 | 95 | 189 | 297 |
SWDL-FL-10- | 2000 | 38 | 88 | 133 | 266 | 418 |
SWDL-FL-10- | 2500 | 49 | 112 | 170 | 340 | 539 |
SWDL-FL-10- | 3000 | 56 | 130 | 198 | 396 | 623 |
12" (DN300) Flange, 36 Heating Elements | ||||||
SWDL-FL-12- | 1000 | 23 | 53 | 81 | 161 | 256 |
SWDL-FL-12- | 1500 | 36 | 83 | 126 | 252 | 396 |
SWDL-FL-12- | 2000 | 50 | 115 | 175 | 350 | 550 |
SWDL-FL-12- | 2500 | 65 | 150 | 228 | 455 | 715 |
SWDL-FL-12- | 3000 | 75 | 173 | 264 | 529 | 831 |
14" (DN350) Flange, 45 Heating Elements | ||||||
SWDL-FL-4- | 1500 | 45 | 104 | 158 | 315 | 495 |
SWDL-FL-4- | 2000 | 63 | 145 | 220 | 440 | 693 |
SWDL-FL-4- | 2500 | 81 | 186 | 284 | 567 | 891 |
SWDL-FL-4- | 3000 | 94 | 217 | 330 | 660 | 1040 |
16″ (DN400) Flange, 72 electric heating elements | ||||||
SWDL-FL-16- | 1500 | 72 | 133 | 200 | 504 | 792 |
SWDL-FL-16- | 2000 | 100 | 232 | 280 | 704 | 1100 |
SWDL-FL-16- | 2500 | 130 | 298 | 365 | 907 | 1420 |
SWDL-FL-16- | 3000 | 150 | 347 | 528 | 1056 | 1664 |
18" (DN450) Flange, 108 heating elements | ||||||
SWDL-FL-18- | 1500 | 108 | 250 | 379 | 756 | 1188 |
SWDL-FL-18- | 2000 | 151 | 348 | 528 | 1056 | 1663 |
SWDL-FL-18- | 2500 | 194 | 446 | 681 | 1360 | 2138 |
SWDL-FL-18- | 3000 | 225 | 520 | 792 | 1584 | 2496 |































