Whether the surface temperature of the electric tubular heating element is even or not is an important technical index to measure the quality of the electric heating pipe. It will directly affect the actual use effect, life, safety and other aspects of the electric tubular heating element. The main reason for the difference of the surface temperature of the electric tubular heating element is the uneven density and eccentricity in the inner part of the electric tubular heating element, which eventually leads to the uneven temperature.
Unevenness of density means that the arrangement space of the electric heating wires in one section of the electric heating pipe is very close, and the arrangement space of the other section is very loose or even drawn into a straight line. At this time, the electric heating pipe will have serious temperature unevenness. If the arrangement of the electric heating wires in the pipe is not uniform, the number of spiral coils of the electric heating wires per unit length is large. As a result, the power of this section will increase with the increase of the number of coils, resulting in the phenomenon of local power increase, resulting in uneven temperature, otherwise, the power per unit length will be small.
The surface load is the power per unit area on the heating surface. As the local power increases, the local surface load increases accordingly. The surface load is closely related to the surface temperature. With the increase of the surface load, the surface temperature of the electric heating pipe increases, the surface load decreases, and the surface temperature of the tubular heating element decreases.
The so-called eccentricity refers to the deviation of the central axis of the spiral electric heating wire from the central axis of the electric tubular heating element, so that the electric heating wire is too close to the wall of the electric tubular heating element on one side, and has a large distance from the other side. Considering the thermal conductivity of the heat transfer medium and the thickness of the heat transfer medium on both sides are not consistent, the temperature on the pipe surface is not uniform.
