Spark Plug Performance Requirements

The main requirements for spark plugs are thermal characteristics, tensile strength, heat resistance, electrical conductivity, insulation strength, sealing, and corrosion resistance.
The spark plug must be heat-resistant. Place the screwed part into a crucible electric furnace or muffle electric furnace that has been heated to 700°C and keep it for 10 minutes, then cool it in the air. There should be no cracks or cracks on the surface of the insulator.
Spark plug sealing performance requirements: After the heat resistance test, when the air pressure difference is 1MPa, the air leakage is not allowed to exceed 40cm3 per minute (if the center electrode is glued with a conductor sealing material, the air leakage is not allowed to exceed 5cm2 per minute )
The spark plug insulator assembly should be able to withstand a power frequency (50Hz) voltage of 2200vV (effective value) for a 30s test
Material: The electrical conductivity of the spark plug center electrode and side electrodes depends on the contact between the electrodes and the mixture. Therefore, the electrodes have extremely high requirements for corrosion resistance. At the same time, the temperature during combustion is extremely high, and the electrode material requires high heat resistance. Therefore, many spark plugs use nickel-manganese alloys. In order to improve the heat resistance, some spark plugs are made of nickel-coated copper. In addition to thermal conductivity, the copper gasket also plays a sealing role. The insulator is made of high alumina ceramics