Basic requirements for electric heating wires for electric heating tubes

Today, let's talk about the core heating element of electric heating tubes - electric heating wires. The electric heating wire in the electric heating tube, which can be called a heating element, also has requirements. The specific requirements are as follows:

(1) Sufficient heat resistance, i.e. minimal oxidation or oxidation at high temperatures;

(2) Has a certain mechanical strength at high temperatures;

(3) Larger than resistance, otherwise the tubular heating element must be made very long and inconvenient to install;

(4) The smaller the temperature coefficient of resistance, the better;

(5) Good processing performance, can be processed into linear, strip or spiral shapes, with good welding performance;

(6) Long term work without aging;

(7) The material source is based on domestic sources, with low cost.

At present, the commonly used materials in China are nickel based alloys and iron-based alloys. Iron chromium aluminum alloy is more brittle than nickel chromium wire when heated, but because it is located in the pipeline and compacted in the filling material, the electric heating wire cannot withstand any colored mechanical pressure during the heating process. Therefore, the manufacturing of tubular electric heating elements does not have the above-mentioned brittle defects. In actual production, the specifications of electric heating wires are between 0.15 and 1.6mm. When the wire diameter is ≥ 0.3mm, O0r25A5 iron chromium aluminum alloy wire is generally used. When the wire diameter p ≤ 0.25, Or20Ni80 nickel chromium alloy wire is used.

In the production process of electric heating tubes, before designing the heating tubes, we will inquire about the working environment of the electric heating tubes, the surface load and working temperature of the electric heating tubes, and select suitable materials for the electric heating wires, mainly using Beijing Shougang or high-end German steel wire BGH electric heating wires.