Main material properties of tubular heating elements

- Apr 27, 2020-

Alloy heating wire heats the material
Alloy heating wire is a kind of high-resistance alloy metal heating material, currently commonly used nickel wire, iron wire two kinds of heating material, and some special heating materials are added with noble metal elements and rare earth elements, its main purpose is to increase the thermal stability of heating element, make its heating uniform. The heating principle of the heating wire is to apply voltage to the resistance wire of the heating material for electric heating, which belongs to the resistance type. When the current flows through the resistance, the power is converted into heat and the heat is transferred to the heated object. To be heated object to undertake heating directly have soybean milk machine, electric water heater, indirect heat transfer to be heated object on have electric rice cooker, electric cooker, two kinds of heating method are applicable to the kitchen appliance that heats through heat transfer.
Magnesia oxide insulation material
Magnesia is a kind of insulating material which is widely used and often used in electric heat pipe components. The mesh size of magnesia oxide refers to the grain size, and its fineness, purity and impurities will affect the quality of the electric heat pipe. Commonly used is medium and low temperature magnesia, suitable for 100400℃ electric heating appliances; High temperature oxidized magnesia is suitable for electric heater of 500-800℃. At present, the development of new technology is fast, and the most commonly used is a modified magnesium oxide, which is suitable for electrothermal products above 800℃. This product is in the oxidized magnesia with the infiltration of liquid silica gel. Magnesium oxide containing silicon material is used in fine heating body components, and its characteristic is good insulation performance. There is also a kind of high purity magnesia oxide, suitable for heating appliances above 1000 ℃, its characteristics are particularly strong insulation, electrical strength up to 2500 V voltage without breakdown, twice higher than the industry standard, high safety performance, has been in guang
dong province a number of electrical appliance manufacturers use. In different product temperature performance requirements, the use of different insulation material not only guarantees the safety of the product but also saves the cost.

Heating of external metal pipe:
Metal outer tube commonly used copper tube, iron tube, stainless steel tube, aluminum alloy tube, shape is all kinds of, diameter of 8-12 mm, wall thickness in 0.5
1.2 mm is more commonly used, mainly used in electric kitchen appliances, electric heating appliances, its characteristics are rapid temperature rise, good insulation performance, suitable for all kinds of climate environment, high safety performance, plus insulation materials can also store heat, easy to manufacture, long service life. The metal outer tube shall be cleaned internally and externally before use to clean the impurities, prevent the impurities from chemical reaction with magnesia, and reduce the insulation property of magnesium oxide. Generally speaking, iron tube is suitable for heating elements of lower temperature than 300℃, copper tube is more used in 400-800 ℃ electric heating appliances, stainless steel tube is suitable for 800-1 200 ℃ heating elements. Food industry is strict to hygienic condition, and stainless steel tube is not easy to rust, so it is often used for food liquid heating, heating food industry.
According to the heating purpose, it can be divided into heating water electric heat pipe, heating air electric heat pipe, heating oil electric heat pipe and heating object electric heat pipe