Introduction:
Electric heating tube, also known as heating tube or heating pipe, is scientifically called tubular electric heating element. It consists of a coiled heating wire (resistance wire) placed inside a metal tube,
[Electric Heating Tube] Electric Heating Tube
and the surrounding gaps are filled with insulating powder (MgO) that has good heat resistance, thermal conductivity, and insulation properties. Both ends of the heating wire have lead-out rods or wires. It features simple structure, high mechanical strength, high thermal efficiency, safety and reliability, easy installation, and long service life. It is widely used in various devices such as saltpeter tanks, water tanks, oil tanks, acid and alkali tanks, melting furnaces for fusible metals, air heating furnaces, drying furnaces, drying boxes, and hot press molds.
Electric heating tubes are electrical components specifically designed to convert electrical energy into heat. Due to their low cost, ease of use, convenient installation, and no pollution, they are widely used in various heating applications.
Classification:
1. By lead-out method: single-head electric heating tube and double-head electric heating tube.
2. By material: stainless steel electric heating tube, quartz electric heating tube, Teflon electric heating tube, titanium electric heating tube.
3. By shape: straight electric heating tube, U-shaped electric heating tube, L-shaped electric heating tube, W-shaped electric heating tube, finned electric heating tube, special-shaped electric heating tube.
4. By application: dry-burning electric heating tube and water-burning electric heating tube.
5. By heating method: conventional resistance heating tube and radiant electric heating tube.
Materials:
Common outer tube materials include In800, In840, 304, 316L, 310S, aluminum, copper, low carbon steel, etc.
Magnesium oxide powder is selected according to different usage requirements, with high-temperature powder, medium-temperature powder, etc.
The resistance wire serves as the heating element, with two common materials: Ni-Cr wire and Fe-Cr-Al wire.
Lead terminal materials generally include stainless steel and free-cutting iron.
Sealing materials include epoxy, silicone, glass, etc.
Tubular electric heating element (referred to as electric heating tube) is an electrical component specifically designed to convert electrical energy into heat. It uses a metal tube as the outer shell (including stainless steel and copper tube), with spiral electric heating alloy wires (nickel-chromium, iron-chromium alloy) uniformly distributed along the central axis inside the tube. The gaps are filled and compacted with magnesium oxide sand that has good insulation and thermal conductivity. Both ends of the tube are sealed with silicone gel. This metal-sheathed electric heating element can heat air, metal molds, and various liquids. Common electric heating tubes include finned electric heating tubes, Teflon electric heating tubes, quartz electric heating tubes, etc. Due to their low cost, ease of use, convenient installation, and no pollution, they are widely used in various heating applications.
Features:
Small size, high power: The heater primarily uses clustered tubular electric heating elements. Fast thermal response, high temperature control accuracy, and high overall thermal efficiency. High heating temperature: The maximum operating temperature of the heater design can reach 850°C. Uniform medium outlet temperature, high temperature control accuracy. Wide application range, strong adaptability: The heater can be used in explosion-proof or ordinary places, with explosion-proof grades up to dⅡB and C, and pressure resistance up to 20MPa. Long life, high reliability: The heater uses special electric heating materials, with low surface power load design and multiple protections, greatly enhancing the safety and lifespan of the electric heater. Fully automatic control: According to requirements, through the heater circuit design, automatic control of parameters such as outlet temperature, flow, and pressure can be achieved, and it can be networked with computers. Significant energy-saving effect: Almost 100% of the electrical energy is converted into heat and transferred to the heating medium.
Common Types:
Finned Electric Heating Tube
A finned electric heating tube is a device that consumes electrical energy to convert it into heat for heating the material to be heated. During operation, the low-temperature fluid medium enters the input port under pressure through the pipeline, flows along the specific heat exchange channels inside the electric heating container, and follows the path designed based on fluid thermodynamics principles to take away the high-temperature thermal energy generated by the electric heating element during operation, thereby raising the temperature of the heated medium. The finned tubular electric heating element has metal散热 fins wound on the surface of the ordinary element, expanding the heat dissipation area by 2 to 3 times compared to ordinary elements. That is, the allowable surface power load of the finned element is 3 to 4 times that of ordinary elements. Due to the shortened length of the element, its own heat loss is reduced. Under the same power conditions, it has the advantages of fast heating, high thermal efficiency, long service life, small heating device volume, and low cost. It can be installed in air blowing ducts or other heating applications for stationary or flowing air.
Flange Electric Heating Tube
A flange electric heating tube (also called immersion electric heater) uses U-shaped tubular electric heating elements. According to the design specifications for different heating media and power configuration requirements, it is assembled on a flange cover and inserted into the material to be heated. The large amount of heat generated by the heating element during operation is conducted to the heated medium, raising its temperature to meet the required process conditions. When 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, achieving temperature control of the resistive load of the heating element. This ensures uniform medium temperature and meets the requirements. When the heating element overheats or the liquid level is low, the interlocking protection device immediately cuts off the heating power supply to prevent damage to the heating element and extend its service life. Flange electric heating tubes are mainly used for heat preservation and heating of materials in various storage tanks, containers, and oil tanks in industries such as petroleum, chemical, food, and machinery. The connection method can be flange type or threaded end face seal.
Features of Ordinary Tubular Electric Heater:
1. This electric heater consists of a heating core and a protective tube. The heating core of the HRY1 sheath-type electric heater uses a tubular electric heating element as the heat source. The protective tube is made of thin stainless steel, which has a large heat dissipation area and fast heat transfer. The terminal part is available in ordinary type (using an iron-drawn cup-shaped cover) and special type (using a bolted explosion-proof device cover seal). The special type meets the requirements of explosion-proof mark dIICT4 and protection level IP65 series standards. 2. The electric heater is connected to the oil tank container body via a flange. The sheath isolates the heating core from the heated oil. When repairing the electric heater, there is no need to drain the oil from the tank; simply remove the heating core and replace it with a new one, making maintenance convenient. 3. During design, the contact area between the sheath and the hot oil should be considered to prevent local carbonization of the oil due to excessively high heating temperature.
