Description about Various Sections and Terminologies of Spark Plug

Stud

This is fixed to the insulator. The high-tension cord is also connected to this.

Corrugations

These provide protection against flash over.

Caulked Portion

The insulator and metal shell are caulked together to ensure a gas tight seal.

Metal Shell

It provides a contact for the socket wrench when screwed in.

Plate Finish

It protects against the chemical corrosion.

Gasket

It prevents leakage of the combustion gas. Sufficient tightening torque must be applied.

Sealing Power

Reinforces mechanical strength to prevent leakage under high pressure and temperature.