Why do industrial spark plugs need to be replaced regularly?

Industrial spark plugs are the core ignition parts of internal combustion engines, gas engines and various heavy machinery. The performance of spark plugs directly affects the combustion efficiency, power output and operating stability of the engine. Although the manufacturing process and material technology of spark plugs are constantly improving, regular replacement is still a necessary measure to ensure the long-term stable operation of the equipment.

1. Wear and performance degradation of spark plugs

(1) Electrode ablation: inevitable loss under high temperature and high pressure

When the spark plug is working, a high-voltage arc will be continuously generated between the center electrode and the side electrode, and the temperature can be as high as 2000°C or more. After long-term use, the electrode will gradually become thinner due to high-temperature oxidation and electrical corrosion, resulting in an increase in the electrode gap. Too large a gap will reduce the ignition energy, resulting in incomplete combustion, reduced power, increased fuel consumption, and even misfire. Experiments show that the electrode gap of nickel alloy spark plugs may expand by 0.1mm every 1000 hours of operation, and needs to be replaced after exceeding the standard value (usually 0.3-1.1mm).

(2) Carbon deposits and pollution: affecting ignition status

In the case of poor fuel quality or air-fuel ratio imbalance, carbon deposits (carbon deposits) are easily formed on the surface of spark plug electrodes and insulators, hindering normal ignition. Carbon particles produced by incomplete combustion can cause engine oil to penetrate into the combustion chamber (such as piston ring wear). Long-term low-speed operation (such as generators and construction machinery idling conditions) will cause carbon deposits to cause spark plug short circuits, insufficient ignition voltage, and even complete failure to ignite in severe cases.

(3) Ceramic insulator aging: high-voltage breakdown risk

The ceramic insulator of the spark plug is responsible for isolating high-voltage current, but under long-term high-temperature conditions, the insulator may have microcracks or surface contamination, resulting in high-voltage leakage (commonly known as "leakage"). The aging of ceramic insulators can cause engine vibration, reduced power, and even damage the ignition coil.

2. Differences in the life of spark plugs made of different materials

The replacement cycle of spark plugs is closely related to their materials. The common types and lifespans are compared as follows: