The formulae specified in this International Standard are intended for the establishment of a uniformly acceptable
method for calculating the pitting resistance and bending strength capacity for the endurance of the mainpropulsion
and auxiliary gears of ships, offshore vessels and drilling rigs, having straight or helical teeth and subject
to the rules of classification societies.
The rating formulae in this International Standard are not applicable to other types of gear tooth deterioration, such
as plastic yielding, micropitting, scuffing, case crushing, welding and wear, and are not applicable under vibratory
conditions where there may be an unpredictable profile breakdown. The bending strength formulae are applicable
to fractures at the tooth fillet, but are not applicable to fractures on the tooth working profile surfaces, failure of the
gear rim, or failures of the gear blank through web and hub. This International Standard does not apply to teeth
finished by forging or sintering. This standard is not applicable to gears having a poor contact pattern.
This International Standard provides a method by which different gear designs can be compared. It is not intended
to assure the performance of assembled drive gear systems. It is not intended for use by the general engineering
public. Instead, it is intended for use by the experienced gear designer who is capable of selecting reasonable
values for the factors in these formulae based on knowledge of similar designs and awareness of the effects of the
WARNING — The user is cautioned that the calculated results of this International Standard should be
confirmed by experience.