scope:

This part of ISO 7919 gives guidelines for applying evaluation criteria of shaft vibration under normal operating conditions, measured at or close to the bearings of coupled industrial machines. These guidelines are presented in terms of both steady running vibration and any amplitude changes which can occur in these steady values. The numerical values specified are not intended to serve as the only basis for vibration evaluation since, in general, the vibratory condition of a machine is assessed by consideration of both the shaft vibration and the associated structural vibration.

This part of ISO 7919 applies to coupled industrial machines with fluid-film bearings, having maximum continuous rated speeds in the range 1 000 r/min to 30 000 r/min and not being limited by size and power (with certain restrictions), comprising

̶  steam turbines and generators with outputs less than or equal to 40 MW;

̶  steam turbines and generators with outputs greater than 40 MW and 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);

̶  rotary compressors;

̶  industrial gas turbines with outputs less than or equal to 3 MW;

̶  turbofans;

̶  electric drives and associated gears, where relevant;

̶  rotodynamic pumps (turbo pumps).

The information relating to pumps provided in this part of ISO 7919 complements that given in ISO 10816-7. In particular, the conditions for in-situ operation, performing acceptance tests and the influence of bearing clearance given in ISO 10816-7 shall be taken into account when evaluating the shaft vibration of pumps.

The following are excluded from this part of ISO 7919:

̶  steam turbines and/or generators with outputs greater than 40 MW and speeds of 1 500 r/min, 1 800 r/min, 3 000 r/min or 3 600 r/min (see ISO 20816-2);

̶  gas turbine sets with outputs greater than 3 MW (see ISO 7919-4 and ISO 20816-2);

̶  machine sets in hydraulic power generating and pump-storage plants (see ISO 20816-5);

̶  rotodynamic pumps including integrated electric motors, i.e. where the impeller is mounted directly on the motor shaft or is rigidly attached to it (see ISO 10816-7);

̶  submerged motor-pumps;

̶  reciprocating pumps;

̶  rotary positive displacement compressors (e.g. screw compressors);

̶  reciprocating compressors;

̶  wind turbines.