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Causes Analyses of the Ultra Low Density Heating Element’s Uneven Heating
- Jan 11, 2018 -


Causes Analyses of the Ultra Low Density Heating Element’s Uneven Heating 


       If there is the uneven heating phenomenon in our daily life, strictly speaking that is the unqualified electric heating products. Here roughly conclude the uneven heating reasons as below:

  • 1. Caused by the non-uniform hardness of the electric heating element resistance wire material:

           Because the hardness of the resistance wire is not uniform, the spiral space of the coiled electric heating wire is not uniform after being stretched. This situation generally occurs in the process of drawing electric heating wire using well return. When winding spiral electric heating wire, uneven tension can also affect the uneven spiral spacing.

  • 2. Caused by the improper design of the electric heating element resistance wire:

           In general, the electric heating wire in the electric heating tube is designed into a spiral shape, namely a spring shape. If the ratio of the diameter d of the winding core rod to the diameter d of the electric heating wire is d / d > 8, sag occurs when the powder is applied, and this is the pitch of the electric heating wire which is upper and lower density.

  • 3. Caused by the inappropriate operation of the electric heating element technology process:

           When adding powder, the exposed rod does not meet the requirements; when it is too short, the electric heating wire is pulled out by knocking at the pipe while adding powder, or when it is too long, the rod is pressed out by knocking at the pipe while adding powder. This causes the glow wire to be locally too thin or locally too dense or even short-circuited with the coil. Improper operation of the tube shrinking process will also affect the uniformity of the distribution of electric heating wires.

  • 4. Caused by the defective electric heating element powder-adding equipment:

           For example, adding equipment amplitude instability, guide rod lifting speed is not uniform, powder leakage speed is fast and slow, and so on. Even if all the parameters are normal, magnesium oxide powder is thin and dense.