ISO/TC 108 - Mechanical vibration, shock and condition monitoring

This document gives guidelines for identifying: a) The typical architectures of touch-down bearing systems to show which components are likely to comprise such systems and which functions these components provide; NOTE Touch-down bearings are also known as “backup bearings”, “auxiliary bearings”, “catcher bearings” or “landing bearings”. Within this document, the term “touch-down bearings” is used exclusively as defined in ISO 14839‑1. b) The functional requirements for touch-down bearing systems so that clear performance targets can be set; c) Elements to be considered in the design of the dynamic system such that rotordynamic performance can be optimized, both for touch-down bearings and active magnetic bearings (AMBs); d) The environmental factors that have significant impact on touch-down bearing system performance allowing optimization of overall machine design; e) The AMB operational conditions that can give rise to contact within the touch-down bearing system so that such events can be considered as part of an overall machine design. It also considers failure modes within the AMB system that can give rise to a contact event. This ensures that the specification of the touch-down bearings covers all operational requirements; f) The most commonly encountered touch-down bearing failure modes and typical mechanisms for managing these events; g) Typical elements of a design process for touch-down bearing systems including the specification of load requirements, the sizing process, the analytical and simulation methods employed for design validation; h) The parameters to be taken into account when designing a touch-down bearing system acceptance test programme including the test conditions to be specified and the associated instrumentation to be used to ensure successful test execution; i) The condition monitoring and inspection methods that allow the status of in-service touch-down bearings to be evaluated and when necessary identifying the corrective actions to be taken; j) The factors to be considered when designing the maintenance regime for a touch-down bearing system including the actions to be taken after specified events have occurred together with any actions to be performed on a regular basis; k) The factors to be considered regarding other life cycle topics (e.g. obsolescence management, de-commissioning and disposal).

This document provides guidelines for the assessment of torsional natural frequencies and component strength, under normal operating conditions, for the coupled shaft train, including long elastic rotor blades, of steam and gas turbine generator sets. In particular, the guidelines apply to the torsional responses of the coupled shaft train at grid and twice grid frequencies due to electrical excitation of the electrical network to which the turbine generator set is connected. Excitation at other frequencies (e.g. subharmonic frequencies) are not covered in this document. No guidelines are given regarding the torsional vibration response caused by steam excitation or other excitation mechanisms not related to the electrical network. Where the shaft cross sections and couplings do not fulfil the required strength criteria and/or torsional natural frequencies do not conform with defined frequency margins, other actions shall be defined to resolve the problem. The requirements included in this document are applicable to a) steam turbine generator sets connected to the electrical network, and b) gas turbine generator sets connected to the electrical network. Methods currently available for carrying out both analytical assessment and test validation of the shaft train torsional natural frequencies are also described. NOTE Radial (lateral, transverse) and axial vibration of steam and/or gas turbine generator sets is dealt with in ISO 20816-2.

This document gives guidance for the selection of vibration generating equipment for multi-axial environmental testing, depending on the test requirements. Multi-axial environmental test equipment dealt with in this document refers to a vibration test system having controlled vibration of more than one degree of freedom, including linear vibration and angular vibration. In this document, one or more exciter per desired degree of freedom is supposed. The guidance covers such aspects of selection as — number, type and models of exciters, — number, type and models of connectors, — system configuration, and — some components.

This document specifies methods for determining the uncertainty of the measurement and evaluation of human exposure to vibration. It applies to measurements of vibration quantities (measurands), calculated following a relevant measurement model on the basis of directly measured values, to evaluate a) human exposure to hand-transmitted vibration at the workplace, b) vibration emission of hand-held and hand-guided machinery in a laboratory setting, c) human exposure to whole-body vibration at the workplace, and d) whole-body vibration emission of vehicles. Examples of the application of the individual methods in practical situations are provided in the annexes. In this document a measurement error is defined as the difference between a measured and a reference quantity value. In this document “uncertainty” does not include errors that result from bad measurement strategies, faulty use of measurement equipment or other mistakes.

This document defines specifications covering laboratory tests for seats designed for passengers and crew in railway tractive and trailer vehicles. It concerns tri-axial rectilinear vibration within the frequency range 0,5 Hz to 50 Hz. It specifies the input test vibration to be used at seat testing. This document makes it possible to characterize, in the form of frequency response functions, the manner in which vibration is transmitted to the seat occupant. It also provides an estimator showing the behaviour of the seat in terms of dynamic comfort perceived by the seated person. Different types of excitations can be used and are described depending on knowledge of the vibration environment encountered by the seat and the capability of the vibration simulator.

This document summarizes descriptive quantities for those responsible (e.g. scientists, safety engineers) for determination of postures for a seated person who is exposed to whole-body vibration. It is the intention that the results of different methods can be easily related to these quantities and that they allow for a common terminology between practitioners. The focus of this document is to offer a collection of ideas on how to measure postures in practice. The postures determined can also be used as a basis for further investigation or as a means of comparison for different methods. Although some of the approaches described here can be applied to standing or recumbent positions, additional considerations are likely to be required in these cases. NOTE 1 This work is closely related to International Standards which focus on static postures (ISO 11226[4]) or on radiologically accessible landmarks, i.e. points on the body (ISO 8727[3]). Additionally, this document deals with dynamic postures where body angles or associated movements are determined visually or by measuring points on the skin or clothing. NOTE 2 Nevertheless, ISO 8727[3] and ISO 11226[4] put forward principles for further extensions of posture determination which are followed in this document, in particular for measurements of body angles. This document does not specify sampling strategies or evaluation methods.

This document sets out guidelines for the specific procedures to be considered when carrying out vibration diagnostics of various types of gas and steam turbines with fluid-film bearings. This document is intended to be used by condition monitoring practitioners, engineers and technicians and provides a practical step-by-step vibration-based approach to fault diagnosis. In addition, it gives examples for a range of machine and component types and their associated fault symptoms. The approach given in this document is based on established good practice, put together by experienced users, although it is acknowledged that other approaches can exist. Recommended actions for a particular diagnosis depend on individual circumstances, the degree of confidence in the fault diagnosis (e.g. has the same diagnosis been made correctly before for this machine), the experience of the practitioner, the fault type and severity as well as on safety and commercial considerations. It is neither possible nor the aim of this document to recommend actions for all circumstances.

This document specifies the requirements for qualification and assessment of personnel who perform machinery condition monitoring and diagnostics using acoustic emission. A certificate or declaration of conformity to this document will provide recognition of the qualifications and competence of individuals to perform acoustic emission measurements and analysis for machinery condition monitoring using acoustic emission equipment. This procedure may not apply to specialized equipment or other specific situations. This document specifies a three-category classification programme that is based on the technical areas delineated herein.

This document specifies methods and procedures for analysing and interpreting vibrotactile perception thresholds and threshold shifts. Procedures for describing statistically significant changes in vibrotactile perception thresholds are recommended. This document is applicable to vibrotactile perception thresholds determined at the fingertips according to the provisions of ISO 13091‑1.

This document describes the coupling parameters between the hands of a machine operator and a vibrating surface of the machine. The coupling between the hand and the vibrating surface can be described using different parameters and component parts of these parameters: — force parameters, such as push, pull and grip; — parameters such as pressure exerted on skin. In addition, Annexes A, B, C, D and E provide guidelines for measuring procedures, the measurement of the force and pressure parameters, and information on the requirements for measuring instrumentation, as well as a calibration method. This document does not deal with forces which act tangentially to the hand.

This document specifies sector specific requirements for organizations ("certification body") operating conformity assessment systems for personnel who perform machinery system condition monitoring, identify machine faults, and recommend corrective action. Procedures for the certification of condition monitoring and diagnostic personnel are specified. NOTE These requirements are in addition to those of ISO/IEC 17000 and ISO/IEC 17024.

This document specifies minimum requirements for personal vibration exposure meters (PVEM). This document is applicable to instruments designed for measurements of whole-body vibration in the context of industrial hygiene applications (according to ISO 2631-1, ISO 2631-2 and ISO 2631-4) and/or hand-arm vibration (according to ISO 5349-1) together with the associated exposure times. This document provides specified design goals and permitted tolerances that define the minimum performance capabilities and functional requirements of instruments designed to measure personal daily vibration exposure. This document does not apply to instruments designed to measure or log exposure times without also performing vibration measurement. Instrumentation of this type is described in ISO/TR 19664.

This document specifies the important technical properties of the different methods for mounting vibration transducers and describes recommended practices. It also shows examples of how accelerometer mounting can influence frequency response and gives examples of how other influences can affect the fidelity of the representation of actual motion in the structure being observed. This document applies to the contacting type of accelerometer which is currently in wide use. It is applicable to both uniaxial and multi-axial transducers. This document can also be applied to velocity transducers. This document enables the user to estimate the limitations of a mounting and consequent potential measurement deviations. Transducer mounting issues are not the only problem that can affect the validity of acceleration measurement. Other such problems include, amongst others: transverse movements, alignment of the transducer, base bending, cable movement, temperature changes, electric and magnetic fields, cable whip and mounting torque. Issues other than mounting and their possible effects are outside the scope of this document.

This document specifies the implementation of a condition monitoring system for wind turbines, with particular focus on monitoring of the drivetrain. Guidance for a practical implementation of the FMSA is provided, as well as guidance for specifying best practices and minimum recommendations regarding the condition monitoring system used for failure mode detection, diagnostics and prognostics of the direct drive and geared wind turbine drivetrain, including: a) main bearing(s); b) gearbox, if applicable; and c) generator (mechanical aspects). This also includes subcomponents such as coupling and the lubrication system. This document provides an overview of the important aspects of condition monitoring of wind turbines and makes references to other standards where in-depth information on the subjects is available.

This document specifies requirements for determining and classifying mechanical vibration of individually housed, enclosed, speed increasing or speed reducing gear units. It specifies methods for measuring housing and shaft vibrations, and the types of instrumentation, measurement methods and testing procedures for determining vibration magnitudes. Vibration grades for acceptance are included. Torsional vibration measurements are outside the scope of this document. It applies to a gear unit operating within its design speed, load, temperature and lubrication range for acceptance testing at the manufacturer's facility. By agreement between manufacturer and customer and/or operator, it can be used for guidelines for on-site acceptance testing and for routine operational measurements. This document applies to gear units of nominal power rating from 10 kW to 100 MW and nominal rotational speeds between 30 r/min and 12 000 r/min (0,5 Hz to 200 Hz). This document does not apply to special or auxiliary drive trains, such as integrated gear-driven compressors, pumps, turbines, etc., or gear type clutches used on combined-cycle turbo generators and power take-off gears. The evaluation criteria provided in this document can be applied to the vibration of the main input and output bearings of the gearbox and to the vibration of internal shaft bearings. They can have limited application to the evaluation of the condition of those gears. Specialist techniques for evaluating the condition of gears are outside the scope of this document. This document establishes provisions under normal steady-state operating conditions for evaluating the severity of the following in-situ broad-band vibration: a) structural vibration at all main bearing housings or pedestals measured radially (i.e. transverse) to the shaft axis; b) structural vibration at thrust bearing housings measured in the axial direction; c) vibration of rotating shafts radially (i.e. transverse) to the shaft axis at, or close to, the main bearings; d) structural vibration on the gear casing. NOTE Vibration occurring during non-steady-state conditions (when transient changes are taking place), including run up or run down, initial loading and load changes are outside the scope of this document.

This document sets out the specific procedures to be considered when carrying out vibration diagnostics of various types of fans and blowers. This document is intended to be used by condition monitoring practitioners, engineers and technicians and provides a practical, step-by-step, vibration-based approach to fault diagnosis. In addition, it gives a number of examples for a range of machine and component types and their associated fault symptoms. The approach given in this document is based on established good practice, put together by experienced users, although it is acknowledged that other approaches can exist. Recommended actions for a particular diagnosis depend on individual circumstances, the degree of confidence in the fault diagnosis (e.g. has the same diagnosis been made correctly before for this machine), the experience of the practitioner, the fault type and severity as well as on safety and commercial considerations. It is neither possible nor the aim of this document to recommend actions for all circumstances.

This document focuses on recommended condition monitoring techniques for detecting and diagnosing developing machine faults associated with the most common potential failure modes for hydro unit components. It is intended to improve the reliability of implementing an effective condition monitoring approach for hydroelectric generating units (hydro units). It is also intended to help create a mutual understanding of the criteria for successful hydro unit condition monitoring and to foster cooperation between the various hydropower stakeholders. This document is intended for end-users, contractors, consultants, service providers, machine manufacturers and instrument suppliers. This document is machine-specific and is focused on the generator, shaft/bearing assembly, runner (and impeller for pumped storage applications), penstock (including the main inlet valve), spiral case and the upper draft tube of hydro units. It is primarily intended for medium to large sized hydro units with more than 50 MVA installed capacity, but it is equally valid for smaller units in many cases. It is applicable to various types of turbines such as Francis, Kaplan, Pelton, Bulb and other types. Generic auxiliary systems such as for lubrication and cooling are outside the scope, with the exception of some monitoring techniques that are related to condition monitoring of major systems covered by this document, such as oil analysis. Transmission systems, civil works and the foundation are outside the scope. This document covers online (permanently installed) and portable instrument condition monitoring and diagnostic techniques for operational hydro units. Offline machine testing, i.e. that which is only done during shutdown, although very important, is not part of the scope of this document. Nor is one-time acceptance and performance testing within the scope. The condition monitoring techniques presented in this document cover a wide range of continuous and interval-based monitoring techniques under generalized conditions for a wide range of applications. Therefore, the actual monitoring approach required for a specific application can be different than that which is recommended in this generalized document.

This document details specifications for the instrumentation and methods to be used for testing fixed temperature sensitivity of vibration transducers. It applies to rectilinear velocity and acceleration transducers. The methods specified use both a comparison to a reference transducer and an absolute measurement by laser interferometer. This document is applicable for a frequency range from 10 Hz to 3 kHz (method-dependent), a dynamic range from 1 m/s2 to 100 m/s2 (frequency-dependent) and a temperature range from ?190 °C to 800 °C (method-dependent). Although it is possible to achieve these ranges among all the described systems, generally each has limitations within them. Method 1 (using a laser interferometer) is applicable to magnitude of sensitivity and phase calibration in the frequency range 10 Hz to 3 kHz at fixed temperatures (see Clause 7). Method 2 (using a reference transducer inside a chamber whose temperature limit is ?70 °C to 500 °C) can be used for magnitude of sensitivity and phase calibration in the frequency range 10 Hz to 1 kHz at fixed temperatures (see Clause 8). Method 3 (using a reference transducer outside the chamber) can only be used for the determination of the temperature response of complex sensitivity over a certain temperature range (see Clause 9). NOTE Method 1 and Method 2 can provide the deviation of complex sensitivity over a certain temperature range if the calibration is also done at the reference temperature (room temperature 23 °C ± 5 °C). To ensure the consistency of the use and test condition, the transducer, its cable and the conditioning amplifier are intended to be considered as a single unit and tested together.

This document specifies requirements and guidelines for the analysis of lubricating oils, hydraulic fluids, synthetic fluids and greases. Tests for electrical insulating oils and heat transfer oil are outside the scope of this document.

This document specifies procedures for measuring mechanical mobility and other frequency-response functions of structures excited by means of an impulsive force generated by an exciter which is not attached to the structure under test. It is applicable to the measurement of mobility, accelerance or dynamic compliance, either as a driving point measurement or as a transfer measurement, using impact excitation. Other excitation methods, such as step relaxation and transient random, lead to signal-processing requirements similar to those of impact data. However, such methods are outside the scope of this document because they involve the use of an exciter which is attached to the structure. The signal analysis methods covered are all based on the discrete Fourier transform (DFT), which is performed mostly by a fast Fourier transform (FFT) algorithm. This restriction in scope is based solely on the wide availability of equipment which implements these methods and on the large base of experience in using these methods. It is not intended to exclude the use of other methods currently under development. Impact excitation is also widely used to obtain uncalibrated frequency-response information. For example, a quick impact test which obtains approximate natural frequencies and mode shapes can be quite helpful in planning a random or sinusoidal test for accurate mobility measurements. These uses of impact excitation to obtain qualitative results can be a first stage for mobility measurements. This document is limited to the use of impact excitation techniques for making accurate mobility measurements.

This document establishes requirements to ensure appropriate exchange of information between manufacturers and users of auxiliary tables with a view to working out related specifications and possibly to comparing, in an objective way, the characteristics supplied by the manufacturers of auxiliary tables and associated guidance systems. This document is applicable to auxiliary tables which include slip tables and head expanders. It does not cover auxiliary tables with several degrees of freedom. This document provides three levels of description of the test equipment, as follows: a) minimum level; b) medium level; c) high level. This document gives a list of characteristics to be specified for each level of description.

This document provides guidance to select a vibration generator that will be used to evaluate frequency responses of a test structure or to study how vibration grows/decreases along the structure. These structural dynamics tests can be carried out under field or laboratory conditions (see the ISO 7626 or ISO 10846[4][5][6][7] series). This document describes the selection procedure in terms of the force developed by a single vibration generator. Meanwhile, to move massive structures such as dams or bridges, an assembly of vibration generators is usually applied. Properly phased generators produce in total the same force as calculated for a single vibration generator (see 6.2.6). Guidance also can be applied for the selection of equipment to be used for modal testing to determine natural frequencies, modal shapes and damping in a structure; however, for such a test, more factors than covered by this document usually need to be considered. This document deals only with translational excitation. For equipment applied to generate angular vibration, see Reference [8].

This document describes the range of idealized values of the apparent mass modulus and phase applicable to seated individuals with and without a back support subjected to x-, y- and z‑axis sinusoidal or broad-band random vibration and to standing individuals subjected to z‑axis sinusoidal or broad-band random vibration under specific experimental conditions. Additionally, this document describes the range of idealized values of seat-to-head transmissibility modulus and phase applicable to seated individuals without a back support subjected to z‑axis sinusoidal or broad-band random vibration. The ranges of idealized values defined in this document are considered to be valid for subjects on a rigid seat (or standing on a rigid platform for z-axis only), with feet supported and vibrated. The range of idealized seat-to-head transmissibility values is considered to be applicable also to the condition with the feet hanging freely. For seated individuals subjected to sinusoidal or broad-band random vibration, the apparent mass values are defined over the frequency range of 0,5 Hz to 10 Hz for the x‑axis and y‑axis, and over the frequency range of 0,5 Hz to 20 Hz for the z‑axis. The frequency and amplitude characteristics of the vibration fall within the range for which most vibration exposure is likely to predominate while driving vehicles such as agricultural tractors, earth-moving machinery and fork-lift trucks. Application to automobiles is not covered by this document in view of the lack of a meaningful database for conditions involving posture and vibration excitation levels most likely associated with car driving. The upper and lower values of modulus and phase defined at each frequency for each of the biodynamic response functions considered represent the range of most probable or idealized values. The middle values represent overall weighted means of the human data and define the target values for general applications. Such applications can involve the development of mechanical analogues for laboratory seat testing, or of functions to correct for the human interface when representing the body as a rigid mass, or the development of analytical human body models to be used for whole-body vibration exposure estimations or for seat and cushion design optimization.

This document provides specific guidance on the interpretation of infrared thermograms as part of a programme for condition monitoring and diagnostics of machine systems. In addition, IR applications pertaining to machinery performance are addressed. This document is intended to: — provide guidance on establishing severity assessment criteria for anomalies identified by IRT; — outline methods and requirements for carrying out thermography of machine systems, including safety recommendations; — provide information on image interpretation, assessment criteria and reporting requirements.

This document provides a general background to balancing technology, as used in the ISO 21940 series, and directs the reader to the appropriate parts of the series that include vocabulary, balancing procedures and tolerances, balancing machines and machine design for balancing. Individual procedures are not included here as these can be found in the appropriate parts of ISO 21940.

This document specifies the instrumentation and procedure to be used for performing calibration of field vibration calibrators (FVCs). It is not applicable to FVCs used for the calibration of transducers. These are covered by ISO 16063‑21. Procedures and requirements of in situ calibration by FVC are beyond the scope of this document. Annex B provides more information on the application of FVC.

This document defines terms relating to rotating machinery equipped with active magnetic bearings. NOTE General terms and definitions of mechanical vibration are given in ISO 2041; those relating to balancing are given in ISO 21940-2; those relating to geometric characteristics such as coaxiality, concentricity and runout are explained in ISO 1101.

This document defines terms and expressions unique to the areas of mechanical vibration, shock and condition monitoring.

This document establishes procedures and guidelines for the measurement and classification of mechanical vibration of reciprocating compressor systems. The vibration values are defined primarily to classify the vibration of the compressor system and to avoid fatigue problems with parts in the reciprocating compressor system, i.e. foundation, compressor, dampers, piping and auxiliary equipment mounted on the compressor system. Shaft vibration is not considered. This document applies to reciprocating compressors mounted on rigid foundations with typical rotational speed ratings in the range 120 r/min up to and including 1 800 r/min. The general evaluation criteria which are presented relate to operational measurements. The criteria are also used to ensure that machine vibration does not adversely affect the equipment directly mounted on the machine, e.g. pulsation dampers and the pipe system. NOTE The general guidelines presented in this document can also be applied to reciprocating compressors outside the specified speed range but different evaluation criteria might be appropriate in this case. The machinery driving the reciprocating compressor, however, is evaluated in accordance with the appropriate part of ISO 10816, ISO 20816 or other relevant standards and classification for the intended duty. Drivers are not included in this document. It is recognized that the evaluation criteria might only have limited application when considering the effects of internal machine components, e.g. problems associated with valves, pistons and piston rings might be unlikely to be detected in the measurements. Identification of such problems can require investigative diagnostic techniques which are outside the scope of this document. Examples of reciprocating compressor systems covered by this document are — horizontal, vertical, V-, W- and L-type compressor systems, — constant and variable speed compressors, — compressors driven by electric motors, gas and diesel engines, steam turbines, with or without a gearbox, flexible or rigid coupling, and — dry running and lubricated reciprocating compressors. This document does not apply to hyper compressors. The guidelines are not intended for condition monitoring purposes. Noise is also outside the scope of this document.

This document addresses human exposure to multiple mechanical shocks, and it formulates requirements for the measurement of multiple shocks. The results of these measurements are then analyzed to provide information for the assessment of the risk of adverse health effects to the vertebral end-plates of the lumbar spine for seated individuals due to compression. Other injuries could develop even when there is no injury to the end plate. NOTE 1 Multiple mechanical shocks are shocks of different magnitude and shape that occur frequently at regular and irregular intervals during the measurement period. NOTE 2 As proposed in the annexes, the assessment of the current injury risk is based on measured representative exposures in combination with the individual exposure history. Prospective risks can be assessed by anticipated exposure durations. Manufacturers of measurement equipment are encouraged to develop a possibility for an on-site evaluation of the exposure. Two exposure regimes are distinguished in this document: one for severe conditions and one for less severe conditions. NOTE 3 Clause 4 contains the delineation of the two regimes. This document is applicable for unweighted vertical accelerations that have peak values up to 137,3 m/s2 (14 g) measured at the seat-occupant interface beneath the ischial tuberosities over a 0,01 Hz to 80 Hz measurement bandwidth. NOTE 4 The measurement bandwith is defined in 5.1. Caution is necessary when applying the method to severe exposures, particularly since peak accelerations of 137,3 m/s2 (14 g) are close to the physical limit that a spine can tolerate.

This document provides guidelines for evaluating the vibration measurements made at the bearings, bearing pedestals or bearing housings and also for evaluating relative shaft vibration measurements made on machine sets in hydraulic power generating and pump-storage plants when the machine is operating within its normal operating range. The normal operating ranges for each type of turbine covered by this document are defined in Annex A. This document is applicable to machine sets in hydraulic power generating plants and in pump-storage plants with typical rotational speeds of 60 r/min to 1 000 r/min fitted with shell or pad (shoe) type oil-lubricated bearings. NOTE The current database includes machine speeds ranging from 60 r/min to 750 r/min (with a very small sample of 1 000 r/min machines). This document defines different limit values of bearing housing and shaft vibration depending on the type of turbine, the orientation of the shaft (i.e. horizontal or vertical) and for each of the bearing locations. This document is based on statistical analysis and provides criteria for the most common types of turbines, pump-turbines and pumps. For specific information on which types of units are covered in this document, see Annex A. Machine sets covered by this document can have the following configurations: a) generators driven by hydraulic turbines; b) motor-generators driven by pump-turbines; c) motor-generators driven by hydraulic turbines and separate pumps; d) pumps driven by electric motors. This document is not applicable to the following unit configurations, parameters and operating conditions: — hydraulic machines with water-lubricated bearings; — hydraulic machines or machine sets having rolling element bearings (for these machines, see IEC 62006 and/or ISO 10816‑3); — pumps in thermal power plants or industrial installations (for these machines, see ISO 10816‑7); — electrical machines operating as motors except for the use of these machines in pump-storage applications; — hydro generators operating as synchronous condensers (with the water in the turbine depressed by compressed air); — assessment of absolute bearing housing vibration displacement; — assessment of axial vibration; — assessment of transient conditions; — non-synchronous operation; — assessment of vibration of the generator stator core or the stator frame level. Measurements made of the bearing housing vibration and shaft vibration occurring in machine sets in hydraulic power generating and pump-storage plants can be used for the following purposes: 1) Purpose A: to prevent damage arising from excessive vibration magnitudes; 2) Purpose B: to monitor changes in vibrational behaviour in order to allow diagnosis and/or prognosis. The criteria are applicable for the vibration produced by the machine set itself. Special investigation is needed for vibration transmitted to the machine set from external sources, e.g. transmitted to the machine via the station foundations.

This document is applicable to land-based gas turbines with fluid-film bearings and power outputs greater than 3 MW and an operating speed under load between 3 000 r/min and 30 000 r/min. In some cases (see the list of exclusions below), this includes other rotating machinery coupled either directly or through a gearbox. The evaluation criteria provided in this document are applicable to the vibration of the main input and output bearings of the gearbox but are not applicable to the vibration of the internal gearbox bearings nor to the assessment of the condition of those gears. Specialist techniques required for evaluating the condition of gears are outside the scope of this document. This document is not applicable to the following: i) gas turbines with power outputs greater than 40 MW at rated speeds of 1 500 r/min, 1 800 r/min, 3 000 r/min or 3 600 r/min (see ISO 20816-2); ii) aero-derivative gas turbines (including gas turbines with dynamic properties similar to those of aero-derivatives); NOTE ISO 3977-3 defines aero-derivatives as aircraft propulsion gas generators adapted to drive mechanical, electrical or marine propulsion equipment. Large differences exist between heavy-duty and aero-derivative gas turbines, for example, in casing flexibility, bearing design, rotor-to-stator mass ratio and mounting structure. Different criteria, therefore, apply for these two turbine types. iii) gas turbines with outputs less than or equal to 3 MW (see ISO 7919-3 and ISO 10816-3); iv) turbine driven generators (see ISO 20816-2, ISO 7919-3 and ISO 10816-3); v) turbine driven pumps (see ISO 10816-7); vi) turbine driven rotary compressors (see ISO 7919-3 and ISO 10816-3); vii) the evaluation of gearbox vibration (see this clause) but does not preclude monitoring of gearbox vibration; viii) the evaluation of combustion vibration but does not preclude monitoring of combustion vibration; ix) rolling element bearing vibration. This document establishes provisions for evaluating the severity of the following in-situ broad-band vibrations: a) structural vibration at all main bearing housings or pedestals measured radial (i.e. transverse) to the shaft axis; b) structural vibration at thrust bearing housings measured in the axial direction; c) vibration of rotating shafts radial (i.e. transverse) to the shaft axis at, or close to, the main bearings. These are in terms of the following: - 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.

ISO 18095:2018 gives guidelines for the monitoring techniques to be considered when setting up a condition monitoring programme for power transformers and includes references to associated standards required in this process. It is intended to help in the implementation of a coherent condition monitoring and condition-based maintenance programme, such as described following ISO 17359. ISO 18095:2018 is applicable to single-phase alternating current power transformers of ≥ 1 kVA and three phase alternating current power transformers of ≥ 5 kVA.

ISO 29821:2018 - gives guidelines for establishing severity assessment criteria for anomalies identified by airborne (AB) and structure-borne (SB) ultrasound, - specifies methods and requirements for carrying out ultrasonic examination of machines, including safety recommendations and sources of error, and - provides information relative to data interpretation, assessment criteria and reporting.

ISO 17359:2018 gives guidelines for the general procedures to be considered when setting up a condition monitoring programme for machines and includes references to associated standards required in this process. This document is applicable to all machines.

ISO/TS 14837-31:2017 gives guidelines to encourage reporting of field measurements of ground-borne noise and vibration in a metric that allows international comparison and future development of empirical models. It also sets out the basic minimum requirements and good practice when taking measurements for the evaluation of human exposure in residential buildings to ensure they are reliable. While national standards or requirements based upon project-specific purposes would normally take priority, this guidance can be used where there are no particular requirements or to provide supplementary guidance. Thereby, this document provides a means of improving general quality and reporting of field measurements in a preferred format. There are a number of reasons for carrying out field measurements of ground-borne noise and vibration arising from rail operations, from complaint investigations to validation of prediction models, diagnostics and research as detailed in ISO 14837‑1:2005, 7.2. In the present document, two levels of evaluation are considered. - Scope 1 corresponds to basic measurements of floor vibration and noise in rooms in buildings to evaluate the human exposure to ground-borne vibration and ground-borne noise. Requirements are presented under two levels of accuracy: basic measurements with minimum accuracy; measurements with reduced uncertainty, also more reproducible and more appropriate for prediction. Ground-borne noise is noise generated by vibrating building elements (e.g. floors, walls and ceilings) in the room of interest and is therefore best expressed by both an acoustic and a vibrational quantity. Its identification as ground-borne noise (as opposed to airborne noise, potentially also present) requires simultaneous noise and vibration measurements. Nevertheless, there are also cases of very low frequency vibration (below 10 Hz to 16 Hz) where only vibration measurements are relevant. Rattle can also arise from vibration, which can be from building components or furniture. This document does not set out to characterize this phenomenon, but to note its presence when it occurs. NOTE In some cases, Scope 1 can relate to measurements on the ground outside a building (to resolve access issues or to comply with national regulations), although measurements at the building are generally preferred. - Scope 2 corresponds to measurements extended to evaluate the vibration immission to buildings, which includes vibration measurements at or near the building foundations and vibration measurements on ground next to the building so that the building coupling loss and building transmissibility can be estimated. Vibration measurements near the tracks (on ground surface or in tunnels) for a proper characterization of the source are outside the scope of this document. Certain requirements are specified in the interest of achieving a consistent minimum data set for each investigation, allowing data comparison between sites.

ISO 18437-6:2017 specifies a standard method for the acquisition and analysis of data obtained using the test methods found in ISO 18437‑1 to ISO 18437‑5, ISO 6721‑4 to ISO 6721‑7 and ISO 6721‑12. ISO 18437-6:2017 is applicable to visco-elastic materials that are thermorheologically simple and that have been tested at equilibrium state for every temperature.

ISO 16079-1:2017 gives guidelines which provide the basis for choosing condition monitoring methods used for failure mode detection, diagnostics and prognostics of wind power plant components.

ISO 16063-33:2017 specifies a method, procedures and the specifications for an apparatus to be used for testing the magnetic field sensitivity of vibration and shock transducers. It is applicable to all kinds of vibration and shock transducers. ISO 16063-33:2017 is applicable for a reference test sinusoidal magnetic field having a root mean square (r.m.s.) value more than 10?3 T at 50 Hz or 60 Hz. Typically, a test magnetic field of 10?2 T at 50 Hz or 60 Hz is used. ISO 16063-33:2017 is primarily intended for those who are required to meet internationally standardized methods for the measurement of magnetic field sensitivity under laboratory conditions. NOTE 1 T (tesla) = 1 Wb/m2.

ISO 13373-9 specifies procedures to be considered when carrying out vibration diagnostics of various types of electric motors. The four motor types covered by ISO 13373-9 are squirrel-cage induction, wound-rotor induction, salient-pole and DC motors. NOTE The first two types are defined in ISO 20958. ISO 13373-9 is mostly applicable to motors with power above 15 kW. ISO 13373-9 is intended to be used by condition monitoring practitioners, engineers and technicians and provides a practical step-by-step vibration-based approach to fault diagnosis. In addition, it gives a number of examples for a range of machine and component types and their associated fault symptoms. The procedures presented in ISO 13373-9 can, in some cases, be applied to other types of electrical machines, such as generators, but there can be other specific techniques associated with such machines that are not included in ISO 13373-9. The use of non-vibration quantities, such as voltage and current, to identify and analyse vibration-related faults in electric motors is outside the scope of ISO 13373-9.

ISO 13373-7:2017 gives guidelines for specific procedures to be considered when carrying out vibration diagnostics of various types of machine sets in hydraulic power generating and pump-storage plants (hydropower units). It is intended to be used by condition monitoring practitioners, engineers and technicians and provides a practical step-by-step vibration-based approach to fault diagnosis. In addition, it includes a number of examples for a range of machine and component types and their associated fault symptoms.

ISO/TR 18570:2017 provides guidance on a supplementary method to that defined in ISO 5349‑1 for measuring and reporting hand-transmitted vibration exposures. The method defined in this document provides an improved assessment methodology for evaluating vascular hand-arm vibration risks (vibration white finger). This document does not apply for other health effects (e.g. sensorineural and musculoskeletal disorders) induced from hand-transmitted vibration exposure (see ISO 5349‑1:2001, Annex Β). ISO/TR 18570:2017 is intended to facilitate future research on hand-arm vibration risks. It can be used to supplement the data given by the ISO 5349‑1 methodology. ISO/TR 18570:2017 cannot be used as an alternative to ISO 5349‑1. Data derived from this document cannot be used in place of ISO 5349‑1 data for fulfilling duties under national regulations, guidance or recommendations for either workplace vibration exposures or machinery vibration emissions. The methodology defined in this document is based on biomechanical and epidemiological studies which are reviewed in Annex A. Also provided in Annex A is tentative information on a relationship between vibration exposure and risk of developing vascular hand-arm vibration disorders.

ISO 20816-2:2017 is applicable to land-based gas turbines, steam turbines and generators (whether coupled with gas and/or steam turbines) with power outputs greater than 40 MW, fluid-film bearings and rated speeds of 1 500 r/min, 1 800 r/min, 3 000 r/min or 3 600 r/min. The criteria provided in ISO 20816-2:2017 can be applied to the vibration of the gas turbine, steam turbine and generator (including synchronizing clutches). ISO 20816-2:2017 establishes provisions for evaluating the severity of the following in-situ, broad-band vibration: a) structural vibration at all main bearing housings or pedestals measured radial (i.e. transverse) to the shaft axis; b) structural vibration at thrust bearing housings measured in the axial direction; c) vibration of rotating shafts radial (i.e. transverse) to the shaft axis at, or close to, the main bearings. These are in terms of the following: - 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. ISO 20816-2:2017 is not applicable to the following: i) electromagnetic excited vibration with twice line frequency at the generator stator windings, core and housing; ii) aero-derivative gas turbines (including gas turbines with dynamic properties similar to those of aero-derivatives); NOTE ISO 3977‑3 defines aero-derivatives as aircraft propulsion gas generators adapted to drive mechanical, electrical or marine propulsion equipment. Large differences exist between heavy-duty and aero-derivative gas turbines, for example, in casing flexibility, bearing design, rotor-to-stator mass ratio and mounting structure. Different criteria, therefore, apply for these two turbine types. iii) steam turbines and/or generators with outputs less than or equal to 40 MW or with rated 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 latter category) (see ISO 7919‑3 and ISO 10816‑3); iv) gas turbines with outputs less than or equal to 40 MW or with rated speeds other than 1 500 r/min, 1 800 r/min, 3 000 r/min or 3 600 r/min (see ISO 7919‑3 or ISO 7919‑4 and ISO 10816‑3 or ISO 10816‑4); v) the evaluation of combustion vibration but does not preclude monitoring of combustion vibration.