Structure introduction and working principle of spark plugs for Petrol Car accessories

1. Steel shell: The lower part of the steel shell is a fine thread, which is used to assemble with the spark plug hole of the cylinder head. The upper part has an external hexagonal nut, which is used to install the spark plug sleeve of Roewe Car to tighten or unscrew the spark plug of Roewe Car.

2. The metal rod is the center electrode. The lower end of the metal rod is in contact with the upper end of the center electrode through the conductor glass body, and the upper end of the metal rod is equipped with a wiring nut.
3. There is a high alumina ceramic insulator between the steel shell and the center electrode to insulate the center electrode when electricity is energized.
4. The lower part of the steel shell is equipped with curved side electrodes.
5. There is a copper gasket in the middle of the outside of the steel shell.
Under the action of high voltage, the air between the center electrode and the side electrode of the Petrol Car spark plug will quickly ionize, forming positively charged ions and negatively charged free electrons. When the voltage between the electrodes reaches a certain value, the number of ions and electrons in the gas increases like an avalanche, causing the air to lose its insulation, and the gap forms a discharge channel, causing a "breakdown" phenomenon. At this time, the gas forms a luminous body, a "spark". As it expands due to heat, a "pop" sound also occurs. The temperature of this kind of electric spark can be as high as 2000~3000℃, which is enough to ignite the mixture in the cylinder combustion chamber.