USCG Exam PracticeBearings, lubrication, and care of machine parts
A vessel with a single tailshaft and water-lubricated stern tube bearings is converted to oil-lubricated bearings. The operator wishes to avoid drawing the shaft at the next scheduled examination. Under 46 CFR §61.20-17(e), which combination of conditions must ALL be satisfied to qualify for this exemption?
- ✓ Bearing clearance readings at each drydock; inboard seal examination at each drydock; semiannual lubricant analysis; and nondestructive testing of the taper or flange bolts at required intervalsCorrect
- B. Bearing clearance readings at each drydock; semiannual lubricant analysis; and visual inspection of accessible shaft portions at each drydock
- C. Semiannual lubricant analysis; nondestructive testing of the taper every 3 years; and inboard seal examination annually
- D. Bearing clearance readings at each drydock; inboard seal examination at each drydock; and annual lubricant analysis
Why A is correct
46 CFR §61.20-17(e) sets out four cumulative conditions for exempting an oil-lubricated tailshaft from being drawn: (1) bearing clearance readings at each drydock or underwater survey; (2) inboard seal assembly examination at each drydock or underwater survey; (3) semiannual lubricant analysis; and (4) nondestructive testing of the taper and keyway (not to exceed 5 years) or of the coupling flange bolts when made accessible. All four must be met; no subset is sufficient.
Cited:46 CFR §61.20-17