Standard for Marine Gear Units: Rating
|Publication Date:||23 August 1994|
This standard is applicable to marine reduction and reversing gears as follows:
- marine propulsion reduction gears driven by internal combustion engines or electric motors from 1500 to 20 000 horsepower (1120 to 14 900 kW) per prime mover, when the rotor speeds do not exceed 3600 rpm.
- marine propulsion reduction gears driven by steam or gas turbine from 1500 to 30 000 horsepower (1120 to 22 370 kW) per prime mover.
- power take-off (PTO) gearing that is integral to the propulsion unit.
- auxiliary propulsion gears.
- combination of drives listed above.
The fundamental rating formulas are applicable for rating the pitting resistance and bending strength of external spur, helical, or double helical involute gear teeth. The formulas evaluate gear tooth capacity as influenced by the major factors which affect gear tooth pitting and gear tooth fracture.
This standard also addresses bearings, clutches, lubricating oil systems, shafts and certain aspects of vibrations.