Vibrationer och stöt. Vibrationsmätning

Kommittébeteckning: SIS/TK 111 (Vibration och stöt)
Källa: ISO
Svarsdatum: den 22 aug 2019
Se merSe mindre

This document describes important technical properties of the different methods for mounting of vibration transducers and describes recommended practices. Furthermore it shows examples concerning influences of the mounting of the accelerometer on the frequency response and other influences that could affect the fidelity of the representation of the actual motion of the structure being observed.

This document applies to the contacting type of accelerometers which are currently in wide use. It is applicable to both uniaxial and multi-axial transducers. This document also applies to velocity transducers.

With this document the user is enabled to estimate the limits of a mounting and consequently potential measurement deviations.

It should be noted that transducer mounting issues are not the only problem that can affect the validity of acceleration measurement. This includes, among others: transverse movements, alignment of the transducer, base bending, cable movement, temperature changes, electric and magnetic fields, cable whip, mounting torque, etc. However, issues other than mounting, and their possible effects are not dealt with in detail in this document.

Kommittébeteckning: SIS/TK 111 (Vibration och stöt)
Källa: ISO
Svarsdatum: den 2 sep 2019
Se merSe mindre

This document specifies methods 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.

This document does not include torsional vibration measurements of a geared system.

It applies primarily to a gear unit operating within its design speed, load, temperature range and lubrication for acceptance testing at the manufacturer's facility. The gear unit may be tested in-situ if agreed upon and operated in accordance with the manufacturer's recommendations. Other International Standards and vibration evaluation may be required for measuring the driver or driven machine in field service.

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 may have limited application to the evaluation of the condition of those gears. Specialist techniques are required for evaluating the condition of gears, which are outside the scope of this document.

This document 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;

d) structural vibration for measuring meshing frequencies on the housing.

These are in terms of vibration under normal steady-state operating conditions.

NOTE Vibration during other (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.