Wartsila Vasa Type: 6R32 Engine Crankshaft Repair
RA Power Solutions was approached by a leading shipping company based in Miami USA regarding a problem faced by them in the crankshaft of Wartsila Vasa Type 6R32 main engine. The vessel was stranded at the Port of Las Calderas in the Dominican Republic.
In fact due to ongoing COVID-19 and omicron infection the flights were closed and on partial resumption of flights two technicians were deputed.
Wartsila Vasa main engine type 6R32 details
We are giving below the major specifications of the crankshaft of Wartsila Vasa type 6R32.
S. NO | Crankshaft Details |
|
1 | Engine Make | Wartsila |
2 | Engine Model | Vasa 6R32 |
3 | Crank pin Diameter Standard | 270 mm |
4 | Crankpin Bearing Width | 98 mm |
5 | Place of execution of crankshaft repair | Port of Las Calderas in Dominican Republic |
Inspection of Wartsila Vasa type 6R32 Crankshaft and observations:
i) On arrival of our technicians the visual inspection of the crankshaft was conducted. The crankpin bearing of crankpin no. 5 was observed damaged and all the connecting rods were removed.
ii) All the crankpins were subject to dimensional inspection for taper & ovality.Our technicians were surprised to see crankpin number 5 which was found to be badly damaged having following dimensions:
a) Minimum dimensions of crankpin no. 5: 269.05 mm
b) Maximum dimensions of crankpin no. 5 : 270.00 mm
Thus the ovality and damage of crankpin to the extent 0.95 mm was observed in comparison to standard diameter of 270 mm. All other crankpins were also subject to dimensional inspection and following details were observed:
STANDARD/SPECIFIED NO. SIZES IN MM | |||||||||
SIZE OF CR JOURNAL | |||||||||
| A | Aa | C | Cc | B | Bb | Min | STD | Ovality |
CR-1 | 269.89 | 269.91 | 269.9 | 269.92 | 269.88 | 269.9 | 269.88 | 270 | 0.12mm |
CR-2 | 269.89 | 269.92 | 269.91 | 269.93 | 269.9 | 269.91 | 269.89 | 270 | 0.11mm |
CR-3 | 269.88 | 269.92 | 269.89 | 269.93 | 269.87 | 269.91 | 269.87 | 270 | 0.13mm |
CR-4 | 269.89 | 269.91 | 269.9 | 269.92 | 269.88 | 269.92 | 269.88 | 270 | 0.12mm |
CR-5 | 269.11 | 269.8 | 269.42 | 269.78 | 269.05 | 269.78 | 269.05 | 270 | 0.95mm |
CR-6 | 269.87 | 269.91 | 269.9 | 269.92 | 269.88 | 269.9 | 269.87 | 270 | 0.13mm |
iii) The hardness of all the crankpins was checked by a portable hardness tester. The hardness of all the crankpins was observed within limits except crankpin no. 5 having hardness of 588 on the HB scale was observed.
iv) The magnetic particle test of all the crankpins was done and no crack was observed.
v) Deflection was observed within limits.
vi) On visual inspection deep line marks & rough surface was observed on balance five number crankpin.
vii) All the connecting rods big end bore was also subject to calibration and connecting rod no. 5 was rejected due to variation in the Big end bore.
Action taken to successfully repair Crankshaft of Wartsila Vasa type 6R32
i) The grinding of crankpin no. 5 was undertaken initially to the undersize of only 0.5 mm. since the depth of damage was on the higher side. Our technicians had no option but to reduce the diameter by 1.5 mm. This was done in consultation with the chief engineer of the vessel. After final grinding the following dimensions were maintained:
a) Minimum diameter of crankpin no. 5: 268.48 mm
b) Maximum diameter of crankpin no. 5: 268.50 mm
The ovality of 0.02 mm was maintained with high surface finish better than the specifications of Wartsila Engine manufacturer.
ii) All pins were polished by a special polishing media and surface finish was improved considerably.
RA Power Solutions have been extending onsite crankshaft repair services for the last more than four decades. All our technicians carry seaman book and can fly to any destination in the world in a short time. We carry the grinding machine and tooling as an accompanying baggage which saves time. Few of our technicians also possess American VISA and can travel to South America, Caribbean etc.
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