What are the special symbols of NGK spark plugs (such as A, B, C)? . )

The first letter at the beginning of the most common NGK spark plug model represents the thread diameter of the spark plug, for example, B stands for 14MM thread, for example, C stands for 10MM thread, D stands for 12MM thread and so on.

For example, BKR6E spark plug, BK stands for screw diameter 14MM, ISO standard length spark plug, R stands for built-in resistance type, 6 stands for calorific value, and E stands for thread engagement length19 mm. ..

When choosing a spark plug, we must first determine whether the spark plug is suitable, which involves thread diameter and thread length. The calorific value and gap related to the performance of spark plugs are also something we must consider. For the electrode gap of NGK spark plug, if it is not listed in the number, it means the standard gap is-0.8 mm.

For more specific reading methods of NGK spark plug number, please refer to the figure below.

Extended data

In the ignition system of gasoline engine, high voltage current is introduced into the cylinder to generate electric spark to ignite the components of combustible mixture. It mainly consists of a connecting nut, an insulator, a connecting screw, a center electrode, a side electrode and a shell, wherein the side electrode is welded on the shell.

The gap between spark plug electrodes has a great influence on the work of spark plug. The gap is too small, the spark is weak, and it is easy to leak electricity due to carbon deposition.

The gap is too large, the required breakdown voltage increases, the engine is not easy to start, and the phenomenon of "fire" is easy to occur at high speed, so the spark plug gap should be appropriate. The spark plug gap used in general battery ignition system is 0.7 ~ 0.8 mm, and the gap of individual spark plugs can reach more than1mm.

Function of spark plug

Spark plug is a component that ignites the mixture of gasoline and air entering the engine combustion chamber and plays the role of a lighter. Because it is a lighter, it must work under the very bad conditions listed below.

1. Insulate the high voltage of 20000V-30000V at high temperature.

2, can repeatedly withstand the explosion pressure of 5Mpa.

3. It can withstand the repeated changes of mixed gas cooling and combustion gas heating (2000-2500℃)

4. The electrode material has corrosion resistance to harmful oxides (lead, sulfur and phosphorus) produced by the combustion of mixed gas.

Refer to Baidu Encyclopedia-Spark Plug