ISO 10816-2:2009

Introduction

ISO 10816-1 is the basic part of ISO 10816 giving the general requirements for evaluating the vibration of various machine types when the vibration measurements are made on non-rotating parts. Part 2 of ISO 10816 gives specific provisions for assessing the severity of vibration measured on the bearing housings or pedestals of large steam turbines and generators. Measurements at these locations characterize the state of vibration reasonably well. Evaluation criteria, based on previous experience, are presented. These can be used for assessing the vibratory condition of such machines.

Two criteria are provided for assessing the machine vibration when operating under steady-state conditions. One criterion considers the magnitude of the observed vibration; the second considers changes in the magnitude. In addition, different criteria are provided for transient operating conditions. However, vibration on non-rotating parts does not form the only basis for judging the severity of vibration. For large steam turbines and generators, it is also common to judge the vibration based on measurements taken on the rotating shafts. For shaft vibration measurement requirements, see ISO 7919-1 and ISO 7919-2.

The evaluation procedures presented in this part of ISO 10816 are based on broad-band measurements. However, because of advances in technology, the use of narrow-band measurements or spectral analysis has become increasingly widespread, particularly for the purposes of vibration evaluation, condition monitoring and diagnostics. The specification of criteria for such measurements is beyond the scope of this part of ISO 10816. They are dealt with in greater detail in ISO 13373 (all parts), which establish provisions for the vibration condition monitoring of machines.

Scope

This part of ISO 10816 establishes provisions for evaluating the severity of in-situ, broad-band vibration measured radial (i.e. transverse) to the shaft axis on all main bearing housings or pedestals and in the axial direction on thrust bearings. These are in terms of:
— vibration under normal steady-state operating conditions;
— vibration during other (non-steady-state) conditions when transient changes are taking place, including run up or run down, initial loading and load changes;
— changes in vibration which can occur during normal steady-state operation.

Part 2 of ISO 10816 is applicable to land-based steam turbines and generators with power outputs greater than 50 MW and a normal operating speed of 1 500 r/min, 1 800 r/min, 3 000 r/min or 3 600 r/min. It is also applicable to steam turbines and/or generators which are directly coupled to a gas turbine (such as for combined-cycle applications). In such cases, the criteria of this part of ISO 10816 apply only to the steam turbine and the generator (including synchronizing clutches). ISO 7919-4 and ISO 10816-4 are applicable to the evaluation of the gas turbine vibration.

The evaluation criteria in Part 2 of ISO 10816 are not applicable to the electromagnetic excited vibration with twice line frequency at the generator stator core and housing.
The numerical values specified are not intended to serve as the only basis for judging the severity of vibration. For large steam turbines and generators, it is also common to judge the vibration based on measurements taken on the rotating shafts. For such vibration measurement requirements, see ISO 7919-1 and ISO 7919-2.

For products relating to ISO 10816, refer to the North Protection Multi Sensor Calibrator, MSC-1015.