RA Power Solution have recently executed repair of crankshaft of auxiliary engine model 7L23/30H MAN B&W at suez port. The crankshaft of MAN B&W model 7L23/30H had major failure as all the crankpins were damaged due to use of bad lubricating oil. It seems that the protocol for the change of lubricating oil as stipulated in the operation manual was not followed.
Deputation of RA Power Solution technicians to Suez port :
RA Power Solutions two technicians along with an onsite crankshaft grinding machine and necessary measuring instruments were deputed to Suez port and boarded the vessel. The inspection of the crankshaft was conducted as per the RA Power Solutions protocol.
Following are the main observations:
(i) On the visual inspection of the crankpins it was observed that all seven crankpins were damaged. The bearing material was embedded on a few of the crankpins. The deep bearing line marks and rough surface are also observed.
(ii) The hardness of the crankpin was taken and no abnormality was observed.
(iii) The crack detection of all seven crankpins was undertaken by the MPI method and no crack was observed.
(iv) On dimensional inspection of the crankpins, ovality in the range of 0.10 mm to 0.26 mm was observed in case of six crankpins. In the remaining one crankpin ovality of 1.40 mm was observed.
The standard details of the crankshaft are as the following :
| S. No. | Crankpin and Main Journal Details | |
| 1. | Engine Make | MAN B & W |
| 2. | Engine Model | 7L23/30H |
| 3. | Crankpin Diameter Standard | 185.00 MM |
| 4. | Crankpin Bearing Width | 70.00 MM |
| 5. | Grinding of Crankpin Number | #01,#02,#03,#04,#05,#06,#07 |
| 6. | Place of Execution of Grinding of Crankpin | Suez Port, Egypt |
| 7. | Name of Shipping Company | Reputed Company from Chennai, India |
Action taken by RA Power Solutions for the successful repair of MAN B&W crankshaft:
(i) Six numbers of crankpins were undersized by 0.5 mm.
(ii) One number of crankpins was undersized by 2.0 mm.
(iii) All the parameters were strictly maintained as per the manufacturer’s requirements and mentioned in the maintenance manual.
RA Power Solutions has been successfully repairing damaged crankshafts for over 45 years. We extend these services all over the world.