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1、BRITISH STANDARD BS 4813:1972 Method of Measuring noise from machine tools excluding testing in anechoic chambers Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 30 08:39:10 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4813:1972 This British Standard, having been approved by the Mechanical Engi
2、neering Industry Standards Committee, was published under the authority of the Executive Board on 30 March 1972 BSI 09-1999 The following BSI references relate to the work on this standard: Committee reference MEE/178 Draft for comment 69/24647 ISBN 580 07450 1 Co-operating organizations The Mechani
3、cal Engineering Industry Standards Committee, under whose supervision this British Standard was prepared, consists of representatives from the following Government departments and scientific and industrial organizations: The Government departments and scientific and industrial organizations marked w
4、ith an asterisk in the above list, together with the following, were directly represented on the committee entrusted with the preparation of this British Standard: Associated Offices Technical CommitteeElectricity Council, the Central Electricity Association of Consulting EngineersGenerating Board a
5、nd the Area Boards in Association of Hydraulic EquipmentEngland and Wales* Manufacturers Ltd.Engineering Equipment Users Association* Association of Mining Electrical andGas Council* Mechanical EngineersInstitution of Civil Engineers* British Chemical Plant Manufacturers Institution of Gas Engineers
6、 AssociationInstitution of Heating and Ventilating British Compressed Air Society*Engineers* British Electrical and Allied ManufacturersInstitution of Mechanical Engineers Association*Institution of Mechanical Engineers British Gear Manufacturers Association(Automobile Division) British Internal Com
7、bustion EngineInstitution of Plant Engineers Manufacturers AssociationInstitution of Production Engineers British Mechanical Engineering Locomotive and Allied Manufacturers ConfederationAssociation of Great Britain British Pump Manufacturers Association*London Transport Executive British Steel Indus
8、try*Machine Tool Trades Association* Crown Agents for Oversea Governments and Ministry of Defence AdministrationsMinistry of Defence, Army Department Department of Employment and National Coal Board Productivity (HM Factory Inspectorate)*National Physical Laboratory Department of the Environment(Dep
9、artment of Trade and Industry) Department of Trade and IndustryRoyal Institute of British Architects Department of Trade and Industry Telecommunications Engineering National Engineering Laboratory*Manufacturing Association Water-tube Boilermakers Association British Federation of Master PrintersInst
10、itute of Physics and the Physical Society British Occupational Hygiene SocietyInstitute of Sound and Vibration Research British Printing Machinery AssociationInstitution of Heating and Ventilating British Ship Research AssociationEngineers Department of Employment and Productivity Institution of Min
11、ing Engineers (HM Senior Medical Inspector of Factories)Machine Tool Industry Research Association Electrical Research AssociationMinistry of Defence (Navy Department) Federation of Manufacturers of Constructional National Sawmilling Association Equipment and CranesSociety of Environmental Engineers
12、 Federation of Master PrintersSociety of Motor Manufacturers and Furniture Industry Research AssociationTraders Ltd. Heating and Ventilating and Air ConditioningTimber Research and Development Manufacturers AssociationAssociation Imperial College of Science and TechnologyTrades Union Congress Instit
13、ute of Marine EngineersUniversity of Southampton Amendments issued since publication Amd. No.DateComments Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 30 08:39:10 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4813:1972 BSI 09-1999i Contents Page Co-operating organizationsInside front cover Fo
14、rewordii 1Scope1 2Definitions1 3Test conditions1 4Measurements2 5Variation of noise with time3 6Presentation of results3 Appendix A Typical measuring positions around machines4 Appendix B Calculation of levels7 Appendix C Recommended layout of results8 Appendix D Machine tool test report11 Figure 1
15、Typical measuring positions around vertical milling machine4 Figure 2 Typical measuring positions around centre lathe having 350 mm diameter swing5 Figure 3 Measuring positions around numerically controlled boring machine6 Table 1 Background noise2 Licensed Copy: sheffieldun sheffieldun, na, Thu Nov
16、 30 08:39:10 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4813:1972 ii BSI 09-1999 Foreword This standard makes reference to the following British Standards: BS 2475, Octave and one-third octave band-pass filters. BS 4196, Guide to the selection of methods of measuring noise emitted by machinery. B
17、S 4197, A precision sound level meter. This British Standard has been prepared as part of the Institutions work on the noise testing of machinery. The committee gratefully acknowledges the help given by earlier work on the noise testing of machine tools by such organizations as The Machine Tool Indu
18、stry Research Association. The object of this British Standard is to define a method whereby the noise of a machine tool may be measured with reasonable accuracy and repeatability but without necessitating the use of facilities and instrumentation unlikely to be in the hands of manufacturers and use
19、rs of the machine tools. Some compromises with acoustically desirable features of a test method have been inevitable but are not considered serious in the context of the basic object. The noise of many machine tools, when in use, is more a function of the load and the workpiece than of the machine t
20、ool itself. Noise levels established during a test with the machine tool in a particular loaded condition may well be peculiar to that condition which must therefore be described in detail and may be agreed between manufacturer and purchaser. A British Standard does not purport to include all the ne
21、cessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pag
22、es 1 to 12, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 30 08:39:10 GMT+00:00 2006, Un
23、controlled Copy, (c) BSI BS 4813:1972 BSI 09-19991 1 Scope This British Standard relates to the procedure to be followed in carrying out noise tests on machine tools. It deals with general conditions, e.g. room suitability, background noise, etc., and with the measuring process, e.g. instrumentation
24、, measuring points, units of measurement, etc., and gives details of a standard format for the statement of results. Where appropriate, the standard accords with BS 4196, which is based on ISO Recommendation R 495. NOTEThe recommendations in the present standard apply to continuous noise measured by
25、 conventional instruments. No completely reliable guidance is as yet available on the measurement of impulsive noise but when circumstances permit consideration will be given to the possibility of making suitable recommendations. The test conditions specified are in general idealized but it is recog
26、nized that it may not always be practicable to achieve them and some indication is accordingly given of permissible departures from the ideal. The machine should be tested in the unloaded condition and preferably also in the loaded condition but the resultant values are not to be quoted without stat
27、ing the condition in which the machine was tested and, if in the loaded condition, what the loading conditions were. It will be realized that these latter cannot be specified here since the variations in the factors that have to be taken into account, such as type of machine, type of material, natur
28、e of operation, speed, method of feed, etc., may be almost endlessly permutated, thus making it impossible to devise standard, universally applicable tests likely to give truly comparable results. A full description of the test piece should be given. Measurements are expressed as sound levels in dB(
29、A) and as band pressure levels in dB for octave bands having centre frequencies from 63 Hz to 8 000 Hz. NOTEThe British Standards referred to in this standard are listed on the inside back cover. 2 Definitions For the purposes of this British Standard the definitions given in BS 4196, together with
30、the following, apply: machine tool a power driven machine, not portable by hand when working, intended to be used for working metal, wood, plastics and other materials by the removal of chips or swarf or by erosion, chipless formation or physico-chemical processing or a combination of some of these
31、techniques 3 Test conditions 3.1 General 3.1.1 The machine should be tested with all the ancillary equipment essential for its operation, for example, hydraulics, power supplies, frequency converters, bar feeds etc. If such equipment is remote from the machine, it should be the subject of separate t
32、ests. 3.1.2 Allowance should be made for running the machine up from cold to normal conditions. 3.2 Specific room suitability. The suitability of a room for testing machine tools may be determined by placing a small broad band random noise source with omnidirectional characteristics in the centre of
33、 the room and determining the sound level at the selected measuring points, either in dB(A) or in dB in each octave band as specified in 4.3, and at corresponding points twice their distance from the source. NOTEIf the outer measuring points are less than 3 m from a reflecting surface, the desired d
34、rop in sound level may not be obtained. The drop in average sound level, determined as in Appendix B, between the inner and outer measuring points should be at least 5 dB. Sufficient measurements should be taken to establish the maximum distance that the inner measuring points can be from the refere
35、nce source whilst still enabling this difference in readings to be achieved; this will indicate the maximum size of machine that can be tested in the room. In situations where the required 5 dB differences in level cannot be achieved, the room may be used for machine noise measurements of a lower or
36、der of accuracy provided that the variations from 5 dB are stated separately. The limitations on the accuracy with which the noise of some machine tools can be measured in a practical situation are both real and significant. The data obtained by a test to this British Standard must therefore be inte
37、rpreted with a proper degree of caution especially when a machine tool may be placed in an acoustical environment different from that in which it was tested; for instance, placing a machine tool in a smaller room having boundary surfaces more reflective of sound will tend to increase the noise level
38、s which would be measured in a repeat test. For presentation of results, the measurements in dB(A) and octave bands shall be averaged in accordance with the procedure in Appendix B and included on the test record sheet. Measurements should be expressed in dB(A) and in octave bands. Variations from 5
39、 dB(A) should be stated. Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 30 08:39:10 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 4813:1972 2 BSI 09-1999 3.3 Site testing. Many machines will be too large for the room under consideration to meet the room suitability criteria and these must be te
40、sted under site conditions. In this case, the machine itself may be used as the reference source and the doubling of distance should be related to the geometric centre or to the major noise source of the machine. 3.4 Background noise. The background noise level when the machine is not on test, expre
41、ssed in either dB(A) or octave bands, as specified in 4.3 should be determined in each measuring position. The readings with the machine running should be taken at the same points and under the same conditions and should exceed the background level by at least 10 dB. When the differences are less th
42、an 10 dB the corrections given in Table 1 should be applied. If the difference between the measured sound and the background noise is less than 3 dB, a valid measurement cannot be obtained. Table 1 Background noise Noise measurements at each measuring point should be recorded for the machine and the
43、 background noise and the corrected values should also be recorded where applicable. Ideally the background noise level should remain constant during the period of test. However, if any changes in the background noise level do occur, then these changes should be noted so that the appropriate correct
44、ions can be made to the total noise. 3.5 Mounting conditions. The machine should be mounted in accordance with the manufacturers instructions. Mounting conditions, e.g. type of floor, anti-vibration mounting, etc., should be recorded. 4 Measurements 4.1 Measuring points 4.1.1 Prescribed path positio
45、ns. The prescribed path should be taken as 1 m from the vertically projected plan of the machine at a height of 1.5 m, ignoring small projections caused by, e.g. handwheels, stop bars, etc. In the case of machine tools whose operation necessitates or permits a change in the projected plan due to, fo
46、r example, a travelling table, the prescribed path should be drawn 1 metre from the extremities of the change in the projection plan. Microphone positions should be at horizontal separations of not more than 1.5 m along the prescribed path around the machine commencing on the major axis of the machi
47、ne. The number of measuring points should not be less than 5 and should include the point at which the sound level in dB(A) is the highest. Typical measuring positions for representative types of machines are illustrated in Appendix A. 4.1.2 Other positions. In addition to the above, measurements sh
48、ould be taken at the operating position and at any other positions that may be occupied by personnel for a significant proportion of their working day. Such measurements should be reported separately and excluded from the calculations of mean sound levels. 4.2 Measuring instruments 4.2.1 Type of ins
49、trument. The instruments used for making measurements for the purpose of the tests specified in this standard should be precision grade sound level meters in accordance with BS 4197 and octave band filters in accordance with BS 2475, used strictly in accordance with the manufacturers instructions. The instruments should be calibrated in accordance with the requirements of these standards both before and after the test. If any other equipment, such as a tape recorder or graphic level recorder is used, its stability and frequency response should be at least equa
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