Design principles and precautions for oven heating tubes

Most oven electric heating tubes generally use finned heating tubes. Sometimes, when making a molded heater, it will be directly made into a duct-type electric heater and placed directly in a large oven for use.

Oven electric heating tube design principles:

(1) The ratio of the total length of the heating zone of the heating tube to the power is 1:1 or 1:1.5 (under the premise of air circulation), that is, one meter of heating length can produce 1KW or 1.5KW (under the premise of air circulation). For the same length, the greater the power, the higher the surface temperature of the heating tube, and the easier it is to burn out.

(2) The shape of the oven electric heating tube is determined according to the shape and size of the oven, the size of the installation space, and the power (conventional ones can be straight rods, U-shaped, W-shaped, etc.).

(3) Finally, consider the installation method to decide whether to use fasteners.

Precautions for using oven electric heating tubes:

(1) The oven must have a temperature control system (electric control cabinet), not only considering the life of the oven electric heating tube, but also considering safety issues.

(2) When installing the oven heating tubes into the oven, the following points should be noted:

A. When arranging the oven heating tubes in the oven, the heating conditions of the first and second rows of oven heating tubes are similar to the heat release conditions of the third and subsequent rows. Therefore, there is no need to install empty tubes and the oven heating tubes can be installed directly.

B. In the circulating air duct, the oven heating tubes not only exchange heat by convection, but also by radiation. This is related to the installation position of the oven heating tubes. The surface temperature of the oven heating tubes installed in the middle is higher, while the surface temperature of the oven heating tubes installed in the side is lower. Therefore, in order to increase the surface load of the oven heating tubes, the number of oven heating tubes arranged horizontally should not be too many.