RA Power Solutions has extended services for onsite repair of main & auxiliary engines for the last 43 years. We have experienced that shipping companies most of the time don’t pay any attention to calibration of connecting rod big and small end bore, this results in a major accident. Recently RA Power Solutions attended to the main engine of Naval Stork Werkspoor S.A. Diesel TMBAS 396 for the major failure of the crankshaft.
The connecting rods were inspected by our technicians and we were surprised to have the following observations:
| DIMENSIONAL REPORT OF CONNECTING ROD AFTER ACCIDENT | |||||||
| STANDARD SIZE: 312.00mm | T2022-08-30 | ||||||
| SERIAL NO. | 1 | 2 | 3 | 4 | 5 | 6 | |
| CYLINDER/CR HOUSING NO. | 1 | 2 | 3 | 4 | 5 | 6 | |
| A | F | -5 | -40 | -32 | 5 | 12 | -3 |
| A | -6 | -32 | -29 | 6 | 11 | 2 | |
| B | F | 8 | -40 | -38 | 7 | -2 | 8 |
| A | 11 | -47 | -45 | 3 | -3 | 6 | |
| C | F | 4 | -4 | 0 | 7 | 3 | 9 |
| A | 3 | -6 | 8 | 4 | 3 | 5 | |
| D | F | 4 | 38 | 35 | 10 | 9 | 8 |
| A | 4 | 40 | 36 | 11 | 8 | 7 | |
| E | F | -4 | 25 | 25 | 11 | 11 | 2 |
| A | -3 | 27 | 27 | 12 | 13 | 5 | |
| MINIMUM | 311.94 | 311.53 | 311.55 | 312.03 | 311.97 | 311.97 | |
| MAXIMUM | 312.11 | 312.4 | 312.36 | 312.12 | 312.13 | 312.09 | |
On going through the above dimensional report we were shocked to know that the standard bore size of the big end is 312.00 mm. The bore size of 311.53 mm to 312.40 mm was recorded. Thus there is an ovality of 0.87 mm. The minimum reading of 311.53 mm shows that there was a shrinkage of the connecting rod’s big end bore resulting in the loss of oil gap and a major accident. You can avoid such a major accident.
Services offered by RA Power for the Calibration of Connecting Rods
- We have a team of factory-trained technicians who can fly down to any site worldwide with calibrated instruments.
- We checked the connecting rod’s big end and small end bore.
- The connecting rod bolt and matching surfacing are subject to MPI for crack detection.
- The elongation of the connecting rod bolt is checked.
- Visual inspection.
For your requirement of connecting rod calibration or assistance, please email us at rajshahani@rapowersolutions.com, or info@rapowersolutions.com, or call us at +91 9582647131 or +91 9810012383.
