Repair of Crankshaft of YANMAR Diesel Engine Model 6N18AL-DV

Following are the details of Repair of Crankshaft of YANMAR Diesel Engine Model 6N18AL-DV undertaken by RA Power Solutions for one of the leading shipping company based in India.

Crankshaft Repair of YANMAR Diesel Engine Model 6N18AL-DV:-

1.   It was reported by one of our client that oil pressure of YANMAR Diesel Engine Model 6N18AL-DV was getting dropped and the traces of white metal were also found in the oil sump.

2.    RAP technicians visited the vessel in Srilanka and on inspection of the crankpin of YANMAR Diesel Engine Model 6N18AL-DV observed excessive ovality in all the six crankpins.

Following are the details: 

Crankshaft Repair of YANMAR Diesel Engine Model 6N18AL-DV

The bearing marks were observed on all crankpins. The crankshaft was also subject to following onsite inspection:-

1.  Hardness of all crankpins was checked and found within the limits as specified by the manufacturer.

2. The deflection reading of crankshaft was taken and it was found within limits.

3. All the crankpins were subject to magnetic particle test for crack detection and no crack or abnormality was observed.

Insitu Grinding of YANMAR Diesel Engine Model 6N18AL-DV

Based on the above observations of the crankpins, it was decided  to grind all six crankpins having bearing width of 59 mm of YANMAR Diesel Engine Model 6N18AL-DV.

RA Power Solutions have been extending onsite crankshaft grinding services all over the world for last forty years.  In order to accommodate onsite crankshaft grinding machine on the crankpin having bearing width of only 59 mm it was a challenge. RA Power Solutions designed an equipment which can sit on the diameter of crankpin of 145 mm and bearing width of only 59 mm which is considered to be very less.All the crankpins of YANMAR Diesel Engine Model 6N18AL-DV were ground to 0.4 mm undersize as per the manufacturer recommendations.

The final crankpin dimensions after grinding were maintained as following:-

As seen from the above readings, the ovality was controlled within 0.02 mm which is better than the tolerances specified by the manufacturer.

Repair under process of crankshaft YANMAR Diesel Engine Model 6N18AL-DV

At the time of final inspection, following parameters were checked and report was prepared.

1.   Dimensional inspection of crankpins for taper and ovality.

2.   Checking of hardness of crankpins.

3.    As a matter of caution, MPI for crack detection was again undertaken after grinding of crankpins.

The inspection reports were documented in RA Power Solutions Format. These reports can also be shared with our clients which are duly signed and stamped by the chief Engineer of the vessel.

RA Power Solutions which has the experience of more than 40 years in the field of onsite grinding and repair of crankshaft has special tooling for repair of crankpins having small bearing width. This is possible as the onsite crankshaft grinding and polishing machines are designed and manufactured by us. We incorporate the changes in the design of the machine as per the site requirement keeping into consideration the limited space available for the fitment of equipment.

Grinding of Crankshaft of YANMAR Diesel Engine Model 6N18AL-DV

The grinding of crankpins of smaller bearing width is always a challenge due to limited availability of space  for fixing of the equipment. We have overcome this problem with the revolutionary design of crankshaft grinding equipment.

Knowing the fact that the leading European and UK based crankshaft grinding companies cannot execute such jobs, we feel proud of successfully executing repair of crankshafts having diameter upto 700 mm. The job of repair of six number of crankpins of YANMAR Diesel Engine Model 6N18AL-DV was executed by our technicians during the sailing of the vessel. This was again possible only because our equipment is designed to absorb the vibrations resulting to the maintenance of close tolerances.

For more information, please email us at rajshahani@rapowersolutions.com, info@rapowersolutions.com, or call us at +91 9582647131 or +91 9810012383.