Industrial electric heater is a kind of high quality and long life electric heating equipment popular at home and abroad. Used for heating, heat preservation and heating of liquid and gaseous medium. When the heating medium is heated through the electric heater chamber under the action of pressure, the principle of fluid thermodynamics is adopted to evenly take away the huge heat generated in the work of the electric heating element, so that the temperature of the heated medium can meet the technical requirements of the user.

The effects of thermal expansion and cold contraction, ablation, oxidation and creep should be considered in the design of industrial electric heaters so as to avoid failure due to deformation in normal operation. The design of the internal structure of the industrial electric heater shall ensure that the material selected for manufacturing the industrial electric heater is not damaged and can still work reliably under the conditions of high temperature or high temperature which may be encountered in its processing. The welding structure design of the industrial electric heater should meet the relevant standards, the welding seam of the industrial electric heater under pressure, especially the part in the container, should be as little as possible, the welding seam setting should be easy to check, the design of the industrial electric heater shell and its accessories under pressure must meet the relevant standards. Industrial electric heaters (including the end) must be sealed, used for corrosive medium heating industrial electric heaters must be corrosion-resistant metal tubes or protective sleeves, to ensure the working life of industrial electric heaters.

The air duct electric heater is mainly used for air heating in the air duct. The specifications are divided into three forms: low temperature, medium temperature and high temperature. The common place in the structure is that the electric heat pipe is supported by steel plate to reduce the vibration of the electric heat pipe.

In addition to overtemperature protection, a combined transport device is also installed between the fan and heater to ensure that the electric heater should be started after the fan starts, and a differential pressure device is added before and after the heater to prevent the fan failure. The gas pressure heated by the channel heater should not exceed 0.3Kg/cm² in general. If the pressure exceeds the above, please choose the circulating electric heater. Low temperature heater gas heating high temperature does not exceed 160℃; Medium temperature type does not exceed 260℃; High temperature type does not exceed 500℃. Air duct electric heater is used for industrial air duct, air conditioning duct and various industries by heating the air to improve the temperature of the output air, generally inserted in the transverse opening of the air duct. According to the working temperature of air duct, low temperature, moderate and high temperature; According to the wind speed in the duct, it can be divided into low wind speed, medium wind speed and high wind speed.

Air duct electric heater, using electric heating method to heat liquid, air drying. Full set of automatic control, power saving, no pipeline leakage, good working environment, rapid heating.

It is suitable for heating in liquid PH≥7, and can be made into daily tubular electric heating element dry burning tube, drying room, oven, static, flowing air, oil, water, press mold and other ways. Sanitary seamless stainless steel pipe, strong corrosion resistance, suitable for low concentration alkaline liquid heating; Duct electric heater adopts low surface power design of 5.6W/cm² to ensure the service life of duct electric heater; The air duct electric heater has good stability and insulation performance, to eliminate the heater leakage, short circuit phenomenon which is often encountered in electroplating factory.

Generally speaking, the explosion-proof electric heating furnace is based on heat conduction oil as the heat carrier. The internal high temperature voltage system is forced to process by the circulating pump of heat conduction oil after electric energy, and the heat of the internal high temperature voltage is transported to one or more electric heating equipment. After the transition function in the high temperature voltage system of the electric heating equipment, the heat conduction oil begins a new heating operation power, that is, through the circulating pump again, back to the electric heating furnace to absorb heat twice and transmit it to the internal high temperature voltage system of the electric heating furnace. After this circulating operation, the electric heating furnace passes through the uninterrupted transfer of heat. The internal high temperature voltage system of electric heating furnace can obtain the power to continue high temperature. Then satisfy the heating medium in the process of high temperature heating demand.

Because the air duct heater is mainly used in industry, in general, according to the temperature requirements, air volume requirements, size, material and so on, the final selection is not the same, and the price is different. In general, the selection can be in accordance with the following 5 points:

First, power selection

The selection of power is to meet the heat required by the heating medium, is to ensure that the heater can achieve the purpose of heating, normal operation of the choice.

Power calculation should consider the following three options:

(1) From the initial state, according to the specified time requirements to achieve the heating medium to the set temperature < working temperature);

(2) under working conditions, the calorific value is enough to maintain the temperature of the medium;

(3) There should be a certain safety margin, generally 1.2.

Obviously, the greater the power selected from Article (1) (2), multiplied by the safety margin is the selected power.

Two, wind speed design

The measurement of wind pressure, wind speed and air volume of duct can be completed by pitot tube, U-type manometer, tilted micromanometer, hot ball anemometer and other instruments. Pitot tube and U-type manometer can test the total pressure, dynamic pressure and static pressure in the air duct. The measured total pressure can know the working condition of the fan and the resistance of the ventilation system. The air volume of the duct can be converted from the measured dynamic pressure of the duct. The wind speed in the duct can also be measured directly with the hot ball anemometer, and the air volume in the duct can be converted from the wind speed.

1. Connect the fan and ventilation duct

2. Use steel coil to detect the diameter of the air duct or the size of the rectangular air duct

3. according to the diameter or rectangular duct size, determine the location of the measuring point

4. Open a round hole with a diameter of 12mm on the air duct at the test position

5. Mark the location of the measuring point on the pitot tube or hot ball anemometer

6. Pitot tube and U-type manometer are connected with latex tube

7. Pitot tube or hot ball anemometer is vertically inserted into the air duct at the measuring hole, so as to ensure that the position of the measuring point must be correct, and pay attention to the direction of the pitot tube probe.

8. Read the total pressure, dynamic pressure and static pressure in the duct directly on the U-shaped manometer, and read the wind speed in the duct directly on the hot ball anemometer.

The calculation formula of electric heating power is p*t

p is power, expressed in KW (kW).

t is time, and the unit is h (hour).

J is electric energy, and the unit is (KWh KWH).

That is, 1500Wx1h=1.5KWx1h=1.5KWh.

The formula here is calculated when the appliance is running continuously.

1. the measurement of electric energy

The unit of electric energy is joule (J), which is commonly used in domestic kilowatt-hours (KWh).

The meter measures the power consumption, and the power consumption is equal to the count difference.

1 degree =1KWh=3.6×10^6J

600r/KWh means 600 revolutions per 1 degree of power consumed. The turntable rotates n times and consumes n/600KWh.

2. Concept and Formula

The speed of consumption of electric energy, electric power is denoted by P.

The power consumed in one second is called the electric power of the appliance.

P equal energy divided by time P=w/t, voltage and current two times P=UI.

The unit of power is watt, 1(W) and so on 1 volt-ampere, 1W=1VA.

We know that p and t are energy dissipation, and W is equal to p times t.