M/T Mainshaft Inspection

1.Inspect the gear surface and bearing surface for wear and damage, then measure the mainshaft at points A, B, C, D and E. If any part of the mainshaft is less than the service limit (except E), replace it with a new one.

Standard:
A (Ball bearing surface): 25.987-26.000 mm (1.0231-1.0236 in.) 
B (Distance collar surface): 28.992-29.005 mm (1.1414-1.1419 in.) 
C (Needle bearing surface): 34.984-35.000 mm (1.3773-1.3780 in.) 
D (Ball bearing surface): 25.977-25.990 mm (1.0227-1.0232 in.) 
E (Pilot bearing surface): 14.870-14.890 mm (0.5854-0.5862 in.) 
Service Limit: A: 25.93 mm (1.021 in.) 
 B: 28.93 mm (1.139 in.) 
 C: 34.93 mm (1.375 in.) 
 D: 25.92 mm (1.021 in.) 

 

2.Inspect the runout by supporting both ends of the mainshaft. Rotate the mainshaft two complete revolutions when measuring the runout. If the runout is more than the service limit, replace the mainshaft with a new one.

Standard: 0.02 mm (0.001 in.) max. 
Service Limit: 0.05 mm (0.002 in.)