Spark Plug in IC Engines

A spark plug in IC engines is a device used to produce spark for igniting the charge of petrol engines. It is always screwed into the cylinder head. It is, usually, designed to withstand a pressure upto 35 bar and operate under a current of 10 000 to 30 000 volts. The spark plug gap is kept from 0.3 mm to 0.7 mm.