The main types of automotive spark plugs.

1. Quasi type spark plug: the insulator skirt is slightly shrunk into the end face of the housing, and the side electrode is outside the end face of the housing, which is the most widely used one.

2, the edge body protruding type spark plug: the insulator skirt is long, protruding outside the end face of the housing. It has the advantages of large heat absorption and good anti-fouling ability, and can be cooled directly by the intake air and reduce the temperature, so it is not easy to cause hot ignition, so the heat adaptation range is wide.

3, electrode type spark plug: the electrode is very thin, characterized by strong spark, good ignition ability, in the cold season can also ensure that the engine quickly and reliably start, wide thermal range, can meet a variety of uses.

4, the seat type spark plug: the shell and screw thread are made into a cone, so you can maintain a good seal without a washer, thus reducing the spark plug volume, which is more favorable to the design of the engine.

5, polar spark plug: the side electrode is generally two or more, the advantage is that the ignition is reliable, the gap does not need to be adjusted often, so it is often used in some gasoline machines where the electrode is easy to ablate and the spark plug gap can not be adjusted often.

6, face jump type spark plug: that is, along the surface gap type, it is one of the coldest type of spark plug, the gap between the center electrode and the end of the shell is concentric. In addition, in order to suppress the interference of the automobile ignition system to the radio, resistance type and shielding type spark plugs are produced. Resistance type spark plug is equipped with 5-10kΩ resistance in the spark plug, shielded spark plug is the use of metal housing to seal the entire spark plug shielding. The shielded spark plug can not only prevent radio interference, but also be used for waterproof and explosion-proof occasions.