This document specifies the general requirements for evaluating the vibration of various coupled industrial machine types with a power above 15 kW and operating speeds between 120 r/min and 30 000 r/min when measurements are made in-situ. Guidelines for applying evaluation criteria are provided for measurements taken on non-rotating and rotating parts under normal operating conditions. The guidelines are presented in terms of both steady running vibration values and in terms of changes to vibration magnitude, which can occur in these steady values. The numerical values presented are intended to serve as guidelines based on worldwide machine experience, but shall be applied with due regard to specific machine features which can cause these values to be inappropriate. In general, the condition of a machine is assessed by consideration of both the shaft vibration and the associated structural vibration, as well as specific frequency components, which do not always relate to the broadband severity values presented.


The machine types covered by this document include:


a) steam turbines and generators with outputs less than or equal to 40 MW (see Note 1 and Note 2);


b) steam turbines and generators with outputs greater than 40 MW which normally operate at speeds other than 1 500 r/min, 1 800 r/min, 3 000 r/min or 3 600 r/min (although generators seldom fall into this category) (see Note 1);


c) rotary compressors;


d) industrial gas turbines with outputs less than or equal to 3 MW (see Note 2);


e) turbofans;


f) electric motors of any type, if the coupling is flexible. When a motor is rigidly coupled to a machine type covered by any other part of ISO20816, the motor may be assessed either against that other part or against ISO 20816-3;


g) rolls and mills;


h) conveyors;


i) variable speed couplings; and


j) blowers or fans (see Note 3).


NOTE 1   Land based steam turbines, gas turbines and g...