The quality of the Heating Element Cartridge Heater is verified in the most intuitive way.

The quality of the Heating Element Cartridge Heater is verified in the most intuitive way. 

1) First wipe the surface of the Heating Element Cartridge Heater, 

2) then turn on the AC 220V power supply (the voltage corresponding to the Heating Element Cartridge Heater) 

3) Dry burned in the air, power off after the surface turns red,

4) After the electric heating tube is completely cooled, wipe it with a napkin, 

5) There should be no black oxidized powder on the white paper (not reacting with oxygen in the air), which means that this electric heating tube is a high-quality Heating Element Cartridge Heater.