Mechanical vibration. Measurement and evaluation of machine vibration. Land-based gas turbines, steam turbines and generators in excess of 40 MW, with fluid-film bearings and rated speeds of 1 500 r/min, 1 800 r/min, 3 000 r/min and 3 600 r/min

2Scope / Description

This document applies to land-based gas turbines, steam turbines and generators (whether or not coupled to a gas turbine and/or steam turbine) with a power output greater than 40 MW, using fluid film bearings and with a rated speed of 1 500 r/min, 1 800 r/min, 3 000 r/min or 3 600 r/min. The criteria provided herein can be used to evaluate the vibration of gas turbines, steam turbines and generators (including synchronous clutches). This document specifies provisions for evaluating the severity of the following broadband vibrations in the field: a) Structural vibrations radial (i.e. transverse) to the axis on all main bearing seats or bearing seats; b) Structural vibrations in the axial direction of the thrust bearing seats; c) Vibrations of the rotating shaft radial (i.e. transverse) to the axis at or near the main bearings. These evaluations cover the following situations:
　——Vibrations under normal steady-state operating conditions;
　——Vibrations under other (non-steady-state) conditions, including transient changes during start-up or shutdown, initial loading and load changes;
　——Vibration changes that may occur during normal steady-state operation. This document does not apply to the following: i) electromagnetically excited vibrations at twice the line frequency at the stator windings, core and casing of generators; ii) aero-derivative gas turbines (including gas turbines with dynamic characteristics similar to aero-derivative gas turbines); iii) steam turbines and/or generators with a power output less than or equal to 40 MW or a rated speed other than 1 500 r/min, 1 800 r/min, 3 000 r/min or 3 600 r/min (although generators rarely fall into the latter category) (refer to ISO 7919-3 and ISO 10816-3); iv) gas turbines with a power output less than or equal to 40 MW or a rated speed other than 1 500 r/min, 1 800 r/min, 3 000 r/min or 3 600 r/min (refer to ISO 7919-3 or ISO 7919-4 and ISO 10816-3 or ISO 10816-4); v) Evaluation of combustion vibrations, but does not exclude monitoring of combustion vibrations.