Fault States Diagnosis of Marine Diesel Engine Valve Based on a Modified VGG16 Transfer Learning Method

Table 2

Degree of valve leakage.

Serial number	Degree of valve leakage	Fault simulation method
1	Normal	Normal exhaust valve
2	Mild gas leakage	Machining one 3 mm × 1 mm slot on the exhaust valve
3	Moderate gas leakage	Machining two 3 mm × 1 mm slots on the exhaust valve
4	Severe gas leakage	Machining three 3 mm × 1 mm slots on the exhaust valve