Devices for adjusting the mass distribution of a rotor and devices to transfer the rotor are not covered by this International Standard, even if they are combined with the measuring station.

Special enclosure features, such as noise reduction, windage reduction or vacuum (which may be required to spin bladed rotors at balancing speed), are not covered by this International Standard.

L'ISO 21940-32:2012 spécifie l'utilisation de demi-clavettes lors de l'équilibrage de composants individuels d'assemblages clavetés. Elle spécifie également le marquage des composants équilibrés conformément à la convention relative aux clavettes utilisée.

L'ISO 21940-32:2012 s'applique aux rotors équilibrés dans une machine à équilibrer et installés dans leur logement ou sur place. La convention relative aux clavettes peut aussi être appliquée quand on mesure le balourd résiduel ou le régime des vibrations de rotors avec des rainures de clavettes mais sur lesquels des éléments rapportés n'ont pas encore été assemblés.

En plus d'être applicable aux clavettes avec une coupe (transversale) constante rectangulaire ou carrée, installées parallèlement à l'axe de l'arbre, l'ISO 21940-32:2012 s'applique également à des clavettes montées sur des surfaces coniques d'arbres, à des clavettes demi-lune, à des clavettes à mentonnet et à d'autres clavettes spéciales. Le principe de la convention relative aux demi-clavettes est appliqué de la façon qui convient à la forme et à l'emplacement particulier de la clavette spéciale.

It includes a classification system that can be applied to machines which is related to their susceptibility to a change in unbalance. Machines are classified into three types of susceptibility and five ranges of sensitivity. The sensitivity values are intended for use on simple machine systems, preferably with rotors having only one resonance speed over their entire operating speed range. The sensitivity values can also be used for machines that have more resonance speeds in their operating speed range if the resonance speeds are widely separated (e.g. by more than 20 %).

The sensitivity values given are not intended to serve as acceptance specifications for any machine group, but rather to give indications regarding how to avoid gross deficiencies as well as specifying exaggerated or unattainable requirements. They can also serve as a basis for more involved investigations (e.g. when in special cases a more exact determination of the required sensitivity is necessary). If due regard is paid to the values given, satisfactory running conditions can be expected in most cases.

The consideration of the sensitivity values alone does not guarantee that a given magnitude of vibration in operating is not exceeded. Many other sources of vibration can occur which lie outside the scope of ISO 21940-31:2013.