ISO 20361-2015 pdf free download

ISO 20361-2015 pdf free download.Liquid pumps and pump units Noise test code Grades 2 and 3 of accuracy
Porn pes etgroupes motopompes pour liquides — Code d’essai acoustique — Classes de precision 2 et 3.
6.1 Basic standard to be used
The A-weighted emission sound pressure level at the work station (see 62) shall be determined using Iso 11203 (method with Q2) that prescribes a derivation of the A-weighted sound pressure level from the A-weighted sound power level. It represents the average A-weighted sound pressure level over the surface enveloping the pump defined in f2.
6.2 Relevant work station
Since liquid pumps have no identifiable work stations, the work station is defined conventionally as being the box-shaped surface enveloping the pump at a distance of I m from the reference box defined in ISO 3744.
6.3 Measurement uncertainty
The measurement uncertainty is that of the relevant standard used for the determination of the sound power level.
7 Installation and mounting conditions
7.1 General
Installation and mounting conditions are also dependent of the grade of accuracy required. For a required grade of accuracy. sound intensity measurements are much less demanding than sound pressure measurements since sound intensity strongly eliminates the effect of extraneous sources such as pipes and valves.
7.2 Noise test situation
7.2.1 General
Noise test situations shall be
— on-site, or
— on shop test stand, or
— specific facility intended for acoustic measurement.
Tests conducted on shop test stand, except for small powers machines using anechoic chambers, are done only for indication and shall not be considered for contractual limits, since such stands are heavily reverberating and measures are depending upon surrounding tested machines.
7.2.2 Test on site
The following actions for improving the acoustic environment shall be taken into account (see 9.2):
— temporary acoustic lagging of piping;
— operating at the minimum of other noise sources;
— temporary screening of the driverand transmission elements for measurement on pumps (pump alone);
— temporary application of absorbing material on reverberating surfaces.
7.2.3 Test on shop test stand
Acoustic feed-back from the throttling device in the outlet piping and the connected auxiliary piping and system shall not influence the measurement of the noise emission of the pump.
Low noise throttling devices should preferably be used.
The following shall be taken into account:
— acoustic lagging of connected pipings;
— operating at the minimum of other noise sources;
— temporary screening of the driver and transmission elements for measurements on the pump alone;
— temporary application of absorbing material on reflecting surfaces;
— use of anti-vibration techniques.ISO 20361-2015 pdf free download.