Analysis of Marine Diesel Engine Parts Abnormal Vibration of Marine Diesel Engine

1. Trouble phenomenon It is normal for the marine diesel engine to produce certain vibration due to its explosive pressure and inertial force during operation. Under certain working conditions, the magnitude and regularity of its vibration are certain.

If abnormal vibration occurs, the following phenomena often occur:

⑴ Vibration of various parts of marine diesel engine is intensified. Especially the high-pressure tubing, intercooler, governor and other parts can see the vibration with the naked eye, and feel numb when touched by hand.

⑵ Accompanied by abnormal vibration, often accompanied by abnormal sound.

2. Reason analysis

⑴The work of each cylinder is unbalanced: the oil supply of each cylinder is unbalanced; the oil supply angle of each cylinder is unbalanced; the compression ratio of each cylinder is unbalanced.

⑵Unbalanced inertial force: the mass error of the piston and connecting rod group of each cylinder is too large; the dynamic balance error of the crankshaft is too large, or the crankshaft is bent and deformed; the flywheel balance is out of tolerance; the turbocharger rotor is out of balance, or the impeller is damaged; the balance shaft gear The assembly position is wrong; the shock absorber fails; the bearing clearance is too large.

(3) Installation foundation and alignment with working machinery: the installation foundation is weak and the rigidity is poor; the base stiffness is insufficient; the installation screws are loose; the ship diesel engine and the working machinery have poor alignment.