Main Engin Piston Overhaul | Boss Fitter - Ship Repair and Maintenance

Main Engin Piston Overhaul

Piston Overhaul

The overhaul process of a piston typically involves the following steps:

Removal: The piston is disassembled from the connecting rod and taken to the workshop for further inspection and maintenance.
Disassembly and Cleaning: The crown (top part), skirt (side part), and connecting rod are separated from each other. They are thoroughly cleaned to remove any dirt, carbon deposits, or contaminants.
Inspection and Measurement: The piston components are inspected for any signs of damage, wear, or deformation. Measurements are taken to ensure they meet the required specifications and tolerances.
Dye Penetration Crack Testing: A dye penetration test may be conducted to detect any surface cracks or defects in the piston components. This test involves applying a dye to the surface, allowing it to penetrate any cracks, and then inspecting the surface for indications of cracks.
Hydraulic Testing: The piston may undergo a hydraulic test to check its structural integrity and resistance to pressure. It is subjected to hydraulic pressure to ensure it can withstand the operating conditions without any leakage or failure.
Cylinder Liner Inspection and Measurement: The cylinder liner, which is the inner surface where the piston moves, is cleaned and inspected for wear or damage. Measurements are taken to ensure the liner's dimensions meet the required specifications.
Documentation: Throughout the overhaul process, detailed records are kept, including the findings of inspections, measurements, and test results. These records serve as a reference and provide a comprehensive report of the piston's condition and the work carried out.
Reassembly: After all necessary maintenance and inspections are completed, the piston components are reassembled. This includes attaching the crown, skirt, and connecting rod together.
Segments and Rings Installation: The piston rings and segments are installed onto the piston. These rings provide a seal between the piston and the cylinder liner, ensuring efficient combustion and minimizing oil consumption.

Once the piston overhaul is finished, the piston can be reinstalled in the engine, and appropriate tests and checks are performed to ensure its proper functioning.