Duct electric heater is an explosion-proof electric heater, which can be used in hazardous locations where explosion may occur. The explosion-proof grade can reach dⅡB and C, and the pressure resistance can reach 20MPa.
Duct electric heater has fast thermal response, high temperature control accuracy, and high overall thermal efficiency. The working temperature is high, the medium outlet temperature is uniform, the application range is wide, and the adaptability is strong. The duct electric heater is made of special electric heating materials, designed with low surface power load, and adopts multiple protections, greatly increasing the safety and service life of the electric heater.
Explosion-proof electric heaters are generally used in hazardous locations where explosion may occur. Since there are various flammable and explosive oils, gases, dusts, etc. in the surrounding environment, once they come into contact with electric sparks, an explosion will occur. Therefore, heating in such occasions requires the use of explosion-proof electric heaters. The internal control system of the electric heater automatically adjusts the output power of the electric heater based on the temperature sensor signal at the output port, so that the medium temperature at the output port is uniform.
If the heated material overheats, causing coking, deterioration, carbonization, and in severe cases, burning out the heating element, it effectively extends the service life of the electric heater. The main explosion-proof measure of the explosion-proof electric heater is that there is an explosion-proof device in the junction box of the heater, eliminating the hidden danger of electric spark ignition.
The resistance wire of the duct electric heater is made of nickel-chromium alloy, with a temperature of up to 800°C or more. Since the power of the electric heater is relatively large, if the user neglects safety, a fire may occur at any time.
What are the causes of fire in electric heaters? How can we prevent fire hazards?
Fire causes mainly include the following:
1. The electric heater is not equipped with a plug, and the wire end is directly inserted into the socket, which easily causes a short circuit and a fire.
2. Placing the energized electric heater on combustible materials or near flammable materials, causing a fire under prolonged high-temperature baking.
3. The user leaves without unplugging the electric heater, causing it to overheat over time and ignite nearby combustibles, resulting in a fire.
4. Repeated repair of the resistance wire and continued use can cause circuit overload and lead to a fire.
Measures to prevent fire hazards:
(1) During use, do not place flammable and explosive items near the electric heater; maintain a certain safe distance.
(2) The safe current-carrying capacity of the electric heater wire must meet the capacity requirements of the electric heater. Industrial electric heaters must be equipped with a separate circuit under any circumstances.
(3) The wire must be equipped with a plug; do not insert the wire end of the electric heater directly into the socket. The electric heater must be placed on a non-conductive, non-combustible material base.
(4) The duct electric heater must be attended during use; unplug it when leaving. In case of a power outage during use, unplug the electric heater promptly and do not forget.
(5) For resistance wires that have been repaired multiple times, it is no longer recommended to use them; replace them with new resistance wires.
(6) If the electric heater wire is aged or damaged, replace it promptly. Electric heaters without a fuse installed in the circuit must not be used.
(7) Flammable and explosive items are strictly prohibited from being dried with an electric heater.
(8) The electric drying oven should have a temperature control device to prevent both excessive temperature and prolonged heating time.
(9) Although the duct electric heater has multiple protection devices, check all wiring terminals before use to ensure they are secure. Take grounding measures to ensure safety.
(10) A filter screen should be installed at the air inlet, and it should be cleaned regularly to prevent various foreign objects from entering and damaging the heating tube or affecting the life and heat dissipation performance of the heating tube.
