ISO 4412-1:1991

SLOVENSKI STANDARD
01-december-1998
)OXLGQDWHKQLND+LGUDYOLND3RVWRSHNXJRWDYOMDQMDUDYQL]UDþQHJDKUXSDGHO
0RWRUML
Hydraulic fluid power -- Test code for determination of airborne noise levels -- Part 1:
Pumps
Transmissions hydrauliques -- Code d'essai pour la détermination du niveau de bruit
aérien -- Partie 1: Pompes
Ta slovenski standard je istoveten z: ISO 4412-1:1991
ICS:
17.140.20 Emisija hrupa naprav in Noise emitted by machines
opreme and equipment
23.100.10 +LGUDYOLþQHþUSDONHLQPRWRUML Pumps and motors
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

IS0
INTERNATIONAL
4412-l
STANDARD
Second edition
1991-08-15
Hydraulic fluid power - Test code for
determination of airborne noise levels -
Part 1:
Pulnps
Transmissions hydrauliques Code d ’essai pour la d&termination du
niveau de bruit a&Hen -
Partie 1: Pompes
Reference number
IS0 4412-1:1991(E)
IS0 4412-1:1991(E)
Contents
Page
1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2 Normative references
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-. 1
3 Definitions
4 Measurement uncertainty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
5 Test environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6 Instrumentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .~. 2
7 installation conditions . 2
8 Operating conditions .
............. 4
9 Location and number of sound measurement points
IO Test procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4’
11 Information to be recorded
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12 Test report
13 Identification statement (Reference to this part of IS0 4412)
Annexes
A Calculation of sound levels . 7
B Errors and classes of measurement .
........... 9
C Guidelines for the application of this part of IS0 4412
D Bibliography .
8 is0 1991
Ail rights reserved. No part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without
permission in writing from the publisher.
international Organization for Standardization
Case Postaie 56 l CH-1211 Geneve 20 l Switzerland
Printed in Switzerland
ii
IS0 4412-1:1991(E)
Foreword
IS0 (the International Organization for Standardization) is a worldwide
federation of national standards bodies (IS0 member bodies). The work
of preparing International Standards is normally carried out through IS0
technical committees. Each member body interested in a subject for
which a technical committee has been established has the right to be
represented on that committee. International organizations, govern-
mental and non-governmental, in liaison with ISO, also take part in the
work. IS0 collaborates closely with the International Electrotechnical
Commission (IEC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an Inter-
national Standard requires approval by at least 75 % of the member
bodies casting a vote.
International Standard IS0 4412-1 was prepared jointly by Technical
Committees lSO/TC 131, Fluid power systems, Sub-Committee SC 8,
Product testing and contamination control and ISO/TC 43, Acoustics.
This second edition cancels and replaces the first edition (IS0
4412-1:1979), of which clauses 12 and 13 have been transferred to form
a new annex A. The former annex A has become annex B, and annexes
C and D have been added.
IS0 4412 consists of the following parts, under the general title Hydraulic
fluid power - Test code for determination of airborne noise levels:
- Part 1: Pumps
- Part 2: Motors
- Part 3: Pumps - Method using a parallelepiped microphone array
Annexes A and B form an integral part of this part of IS0 4412. Annexes
C and D are for information only.
. . .
Ill
IS0 4412=1:1991(E)
Introduction
In hydraulic fluid power systems, power is transmitted and controlled
through a liquid under pressure in a closed circuit. Pumps are compo-
nents which convert rotary mechanical power into fluid power. During
the process of converting mechanical power into hydraulic fluid power,
airborne noise, fluid-borne vibrations and structure-borne vibrations are
radiated from the pump.
The airborne noise level of a hydraulic fluid power pump is an important
consideration in component selection. The noise measurement tech-
nique must, therefore, be such as to yield accurate appraisals of these
airborne noise levels. The determination of noise levels is complicated
by the interactions which occur during noise measurements. The fluid-
borne and structure-borne vibrations from the pump can be transmitted
to the circuit and ultimately give rise to background airborne noise lev-
els which could affect the determination of the pump airborne noise
levels.
The procedures described in this part of IS0 4412 are intended to
measure only the airborne noise radiated directly from the pump under
test.
IS0 4412-1:1991(E)
INTERNATIONAL STANDARD
Hydraulic fluid power - Test code for determination of
airborne noise levels -
Part 1:
Pumps
on this part of IS0 4412 are encouraged to investi-
1 Scope
gate the possibility of applying the most recent edi-
tions of the standards indicated below. Members of
This part of IS0 4412 establishes a test code de-
IEC and IS0 maintain registers of currently valid In-
scribing procedures, based on IS0 2204, for the de-
ternational Standards.
termination of the sound power levels of a hydraulic
fluid power pump, under controlled conditions of in-
IS0 3448:1975, lndustrial liquid lubricants - IS0 vis-
stallation and operation, suitable for providing a ba-
cosify classification.
sis for comparing the noise levels of pumps in terms
of:
IS0 3744:1981, Acoustics - Determination of sound
power levels of noise sources - Engineering meth-
-
A-weighted sound power level;
ods for fi-ee-field conditions over a reflecting plane.
-
octave band sound power levels.
IS0 3745:1977, Acoustics - Determination of sound
From these sound power levels, if required, refer- power levels of noise sources - Precision methods
ence sound pressure levels may be calculated for for anechoic and semi-anechoic rooms.
reporting purposes in accordance with annex A.
IS0 55983985, Fluid power systems and components
For general purposes, the frequency range of inter-
- Vocabulary.
est includes the octave bands with centre fre-
quencies between 125 Hz and 8000 Hz.?
IS0 6743-4:1982, Lubricants, industrial oils and re-
lated products (class L) - Classification, - Part 4:
Guidelines for the application of this part of IS0 4412
Family N (Hydraulic systems).
are given in annex C.
IEC 50(801): 1984, lnternational Electrotechnical Vo-
This part of IS0 4412 is applicable to all types of
cabulary - Chapter 80 1: Acoustics and elec tro-
hydraulic fluid power pumps operating under
acoustics.
steady-state conditions, irrespective of size, except
for any limitations imposed by the size of the test
IEC 65111979, Sound level meters.
environment (see clause 5).
2 Normative references 3 Definitions
The following standards contain provisions which, For the purposes of this part of IS0 4412, the defi-
through reference in this text, constitute provisions nitions given in IS0 5598, IEC 50 and the following
of this part of IS0 4412. At the time of publication, definitions apply. It is accepted that the latter defi-
the editions indicated were valid. All standards are nitions may differ from those in other specific Inter-
subject to revision, and parties to agreements based national Standards.
1) 1 Hz = 1 s-1
IS0 4412-1:1991(E)
3.1 free sound field: Sound field in a homogeneous,
isotropic medium free of boundaries. Table 1 - Standard deviation of sound power level
NOTE 1 In practice, it is a field in which the effects of
Standard deviation, dB,
the boundaries are negligible over the frequency range
of interest.
for octave bands centred on:
125 Hz 250 Hz
500 Hz 1000 Hz to 8000 Hz
3.2 free field over a reflecting plane: Field produced
4000 Hz
by a source in the presence of one reflecting plane
on which the source is located.
590 33 290 zo
3.3 reverberant sound field: That portion of the
The standard deviations given in table 1 include the
sound field in a test room over which the influence
of sound received directly from the source is negli- effects of allowable variations in the positioning of
the measurement points and in the selection of any
gible.
prescribed measurement surface, but exclude vari-
ations in the sound power output of the source from
3.4 anechoic room: Test room having boundaries
test to test.
which absorb essentially all of the incident sound
energy over the frequency range of interest, thereby
NOTE 5 The A-weighted sound power level will in most
affording free-field conditions over the measurement
practical cases be determined with a standard deviation
surface.
of approximately 2 dB.
3.5 mean-square sound pressure: The sound
5 Test environment
pressure averaged in space and time on a mean-
square basis.
Tests shall be conducted in an environment which
In practice, this is estimated by space and time provides “free-field over a reflecting plane” con-
NOTE 2
averaging over a finite path length or over a number of
ditions which meet the environmental qualification
fixed microphone positions.
requirements described in IS0 3744:1981, clause 4
and annex A.
3.6 mean sound pressure level: Ten times the log-
For more precise measurements, conduct tests in
arithm to the base 10 of the ratio of the mean-square
accordance with IS0 3745.
sound pressure to the square of the reference sound
pressure, in decibels (dB).
6 Instrumentation
NOTE 3 The weighting network or the width of the frer
quency band used should always be indicated; for exam-
6.1 The instrumentation used to measure fluid
ple, A-weighted sound pressure level, octave band sound
pressure level. The reference sound pressure is 20 [+ ‘a*). flow, fluid pressure, pump speed and fluid tempera-
ture shall be in accordance with the recommen-
dations for “industrial class” accuracy of testing; i.e.
3.7 sound power level: Ten times the logarithm to
class C given in annex B.
the base 10 of the ratio of a given sound power to
the refere nce soun d power , in decibels.
6.2 The instrumentation used for acoustical
N ’OTE 4 The weighting network or the width of the fre-
measurements shall be in accordance with IEC 651.
quency band used should always be indicated. The refer-
This instrumentation shall be in accordance with
ence sound power is 1 pW3).
IS0 3744 for both performance and calibration; i.e.
type 2 instruments for engineering (grade 2)
38 . volume of source under test: Volume of the en-
measurements.
velope of the whole pump under test.
7 Installation conditi ’ons
4 Measurement uncertainty
7.1 Pump location
,
Methods of measurement should be used which
The pump may be located in any position consistent
tend to result in standard deviations which are equal
with the source installation and measurement sur-
to or less than those specified in table 1. Methods
face (or microphone traverse) requirements speci-
given in IS0 3744 meet this requirement.
fied in IS0 3744 for the test environment being used.
= 10--S N/m*
2) 1 PPa
3) 1 pw = 10-Q w
IS0 4412-1:1991(E)
least 15 m of hose shall be used to meet this re-
7.2 Pump mounting
quirement.
7.2.1 The pump mounting shall be constructed so
that it will minimize the noise radiated by the
7.4.6 A stable load valve shall be used.
mounting as a result of pump vibrations.
Unstable load valves in the discharge line can
NOTE 6
7.2.2 The mounting bracket shall be constructed of generate and transmit noise through the fluid and piping
which can emerge as airborne sound at the pump.
high-damping material or with sound-damping and
sound-insulating material applied to the bracket as
required.
7.4.7 The load valve shall be positioned far from
the pump, preferably outside the test room, to mini-
7.2.3 Vibration isolation techniques, if needed,
mize the interaction. The load valve shall be located
shall be used even if the pump is usually securely
close to the pump only when adequate control of its
mounted.
acoustic performance can be provided.
7.2.4 Flange mountings that are as small as prac-
7.4.8 All fluid lines and load valves in the test
tical shall be used so as to minimize interference
space shall be wrapped with sound-isolating ma-
with radiation of sound towards the shaft end of the
terials, if required (see 10.1). Material having a
pump.
sound-transmission loss of at least 10 dB at 125 Hz,
and a greater loss at higher frequencies, shall be
7.3 Pump drive
used.
The drive motor shall be located outside the test
space a
...