1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-18893-1 SANS 1470-4:2008Edition 2SOUTH AFRICAN NATIONAL STANDARD Sound power labelling Part 4: Pneumatic equipment Published by Standards
4、South Africa 1 dr lategan road groenkloof private bag x191 pretoria 0001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa SANS 1470-4:2008 Edition 2 Table of changes Change No. Date Scope Acknowledgement Standards South Africa wishes to acknowled
5、ge the valuable assistance derived from publications of the following organizations: Council of the European Communities International Organization for Standardization Foreword This South African standard was approved by National Committee StanSA TC 76, Acoustics, electro-acoustics and vibration, in
6、 accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. This document was published in April 2008. This document supersedes SABS 1470-4:1997 (edition 1.1). SANS 1470 consists of the following parts, under the general title Sound power labelling: Pa
7、rt 1: Compressors. Part 2: Welding generators. Part 3: Rotating electrical machinery. Part 4: Pneumatic equipment. Annex A forms an integral part of this document. SANS 1470-4:2008 Edition 2 1 Contents Page Acknowledgement Foreword 1 Scope 3 2 Normative references 3 3 Definitions 4 4 Requirements 4
8、4.1 Labelling 4 4.2 Noise emission 5 5 Inspection and testing . 5 5.1 Inspection 5 5.2 Test for noise emission. 5 5.3 Modifications to the test method described in SANS 3744. 5 Figures 1 to 13 8-17 Annex A (normative) Two-surface method to determine the environmental correction K2for in-situ measure
9、ments . 18 Bibliography. 20 SANS 1470-4:2008 Edition 2 2 This page is intentionally left blank SANS 1470-4:2008 Edition 2 3 Sound power labelling Part 4: Pneumatic equipment 1 Scope 1.1 This standard covers the requirements for the labelling of pneumatic equipment with a noise emission value and spe
10、cifies the test method to be used for the verification of the labelled value. NOTE 1 The “two-surface method“ (see A.4.3 of SANS 3744:1994) to determine the environmental correction is given in annex A. NOTE 2 This standard refers to SANS 3744 and specifies an engineering method of measuring the sou
11、nd pressure levels at prescribed microphone positions on a rectangular parallelepiped surface that envelops the pneumatic machine under investigation. NOTE 3 For planning purposes, additional information will be required, e.g. measurements of the octave or one-third octave band pressure levels. 1.2
12、This standard does not cover devices emitting isolated sound bursts (e.g. low-frequency pile-drivers) or a series of sound pulses with a repetition frequency lower than 10 Hz. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated
13、references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. Information on currently valid national and international standards can be obtained from Standards South Africa. SANS 656, Sound level meters. SANS 65
14、8, Integrating-averaging sound level meters. SANS 3744:1994/ISO 3744, Acoustics Determination of sound power levels of noise sources using sound pressure Engineering method in an essentially free field over a reflecting plane. SANS 61672-1/IEC 61672-1, Electroacoustics Sound level meters Part 1: Spe
15、cifications. SANS 61672-2/IEC 61672-2, Electroacoustics Sound level meters Part 2: Pattern evaluation tests. SANS 1470-4:2008 Edition 2 4 3 Definitions For the purposes of this document, the definitions given in SANS 3744 and the following definitions apply. 3.1 A-weighted sound power level LWAthe s
16、ound power level of a machine, determined in accordance with the test method specified in this standard, with frequency weighting A (see SANS 656, SANS 658, SANS 61672-1 and SANS 61672-2) selected on the measuring instruments NOTE A-weighted sound power levels are measured in decibels. 3.2 batch a n
17、umber of pneumatic machines of the same performance and manufactured to the same technical specification by one manufacturer NOTE A batch may either be an entire production series or a portion thereof. 3.3 batch labelling a single labelled value (Lc) applied to a batch of pneumatic machines 3.4 labe
18、lled value Lcan integer value, determined by the manufacturer, representing the maximum sound power level of a pneumatic machine 3.5 near field sound field a sound field near a sound source where instantaneous sound pressure and particle velocity are substantially out of phase 3.6 pneumatic equipmen
19、t mechanical equipment that depends on compressed gas for operation NOTE Typical machines include the following: Rock-drills (e.g. sinkers and feedleg drills), paving-breakers, picks and spades, chippers, rivetters, scalers, sheeting, spike-and-pin-drivers, rammers and tampers, grinders, sanders, po
20、lishers, drills, tappers, nibblers, files, saws, motors, pumps and winches, screwdrivers and nut-setters, impact wrenches and hoists. 4 Requirements 4.1 Labelling Each pneumatic machine shall bear a label that contains at least the following information: a) the labelled value Lc; b) the letter “B“ o
21、r “I“ to indicate batch labelling or individual labelling, respectively; and SANS 1470-4:2008 Edition 2 5 c) the identification of the labelled product by means of a serial number. NOTE 1 As an example, the labelling for a pneumatic machine of a given power can be as follows: Labelling Interpretatio
22、n (B) Lc97 23456 “(B)“ indicates that this pneumatic machine is one of a batch that are all labelled with the same value: 97. The labelled value in accordance with this standard is 97. “23456“ is the serial number of the pneumatic machine. NOTE 2 The labelled value may be displayed on the existing s
23、pecification/information plate affixed to the pneumatic machine. NOTE 3 For assessment purposes, e.g. the existence of tonal components, or for planning purposes, additional spectral information for different operating conditions will be required. 4.2 Noise emission When tested in accordance with 5.
24、2, a pneumatic machine shall have an A-weighted sound power level LWAnot exceeding the labelled value Lc. 5 Inspection and testing 5.1 Inspection Inspect each pneumatic machine for compliance with 4.1. 5.2 Test for noise emission NOTE The standard deviation of A-weighted sound power levels determine
25、d in accordance with this standard is approximately 2 dB for a source that emits noise without pronounced spectral deviations. Use the test method described in SANS 3744, modified as described in 5.3, to determine the A-weighted sound power level LWAof the pneumatic machine and check for compliance
26、with 4.2. 5.3 Modifications to the test method described in SANS 3744 5.3.1 Criterion for adequacy of the test environment (see 4.1 and 4.2 of SANS 3744:1994) When the test is to be carried out indoors, use one of the methods described in annex A of SANS 3744:1994 to determine the environmental corr
27、ection K2. If the environmental correction K2exceeds 2 dB, the test environment is not suitable for measurements in accordance with this standard. NOTE See NOTE 2 to 1.1. SANS 1470-4:2008 Edition 2 6 5.3.2 Criterion for background noise Determine the correction for the background noise (K1) in accor
28、dance with 8.3 of SANS 3744:1994. Averaged over the microphone positions, the level of the background noise shall be at least 6 dB, but preferably more than 15 dB, below the sound pressure level to be measured. 5.3.3 Instrumentation (see clause 5 of SANS 3744:1994) When integrating the squared signa
29、l over a fixed time-interval, use a type 1 integrating device or system that complies with the requirements of SANS 656, SANS 658, SANS 61672-1 and SANS 61672-2. 5.3.4 Operation of the pneumatic equipment to be tested (see clause 6 of SANS 3744:1994) Operate the machine as for normal continuous serv
30、ice at rated supply pressure. Measure the air pressure with the machine in operation. Avoid freezing of the exhaust. Use the type, quality and quantity of lubricant recommended by the manufacturer. The geometric centre of the machine under test should be approximately 1 m above the reflecting plane.
31、 Avoid direct discharge of the exhaust air onto the loading device, the reflecting plane or directly towards the microphone positions. 5.3.5 Loading and operation of percussive machines a) Rock-drills. Operate the different types of rock-drills, such as sinkers and feedleg drills (see figures 1 and
32、2), as follows: 1) Drill into granite or other stone material, with a compressive strength in the range 15 000 N/cm to 25 000 N/cm, until at least 0,5 m of the steel of the drill has penetrated into the rock and between 0,5 m and 2,0 m of the steel remains outside the rock. 2) Use a feeding force th
33、at gives maximum guaranteed penetration rate. NOTE Details of the mounting and feeding device shall be recorded. b) Track-drills. Operate track-drills and similar carrier-mounted machines (see figure 3) as specified in 5.3.5(a). c) Paving-breakers, picks and spades. Operate the machine (see figure 4
34、) as follows: 1) hold the machine vertically, with a standard steel embedded in a concrete block; 2) hold the machine down firmly; and 3) ensure that the exposed length of steel, with the machine in place, is between 0,2 m and 0,3 m. d) Chippers, rivetters, scalers, sheeting, spike-and-pin-drivers.
35、Operate the machine with the working tool embedded in a wooden block (see figure 5) resting on a bed of sand. e) Rammers and tampers. Hold the machine vertically while ramming the sand as illustrated in figure 6. SANS 1470-4:2008 Edition 2 7 5.3.6 Loading of non-percussive machines a) Rotary machine
36、s. Operate rotary machines such as grinders, sanders, polishers, drills, tappers, nibblers, files, saws, motors, pumps and winches, in the positions illustrated in figures 7 to 10. Conduct sound pressure level measurements with the machine on-load and operating at the speed at which maximum power oc
37、curs. If the speed at maximum power is not known, operate the machine at 50 % of free speed if it has no governor, and at 80 % if it is fitted to a governor. b) Screwdrivers and nut-setters. Operate the machine in the positions illustrated in figures 7 and 8. Conduct sound pressure level measurement
38、s as follows: 1) Test the following as in 5.3.6(a): i) machines without clutches; ii) machines with automatic means of complete disengagement of the motor; and iii) machines with automatic means of shut-off of the motor. 2) Test machines with clutches that continue to ratchet when the set torque has
39、 been reached, in the ratchetting condition, with the clutch set at 50 % maximum torque and with the output shaft stationary. c) Impact wrenches. Operate the machine in the position illustrated in figure 11 or figure 12. Conduct sound pressure level measurements with the machine so loaded that the o
40、utput shaft rotates at less than 50 r/min. d) Hoists. Operate the machine in the position illustrated in figure 13. Conduct sound pressure level measurements with the machine at rated load and rated speed. 5.3.7 Measurement surface and microphone positions (see 7.3 of SANS 3744:1994) a) Measurement
41、surface. Use a rectangular parallelepiped at a constant distance of 1 m from the reference surface. b) Key microphone positions. Use the microphone positions described in 7.3.1 of SANS 3744:1994. c) Additional microphone positions. If measurements at additional microphone positions are required see
42、7.3.2 of SANS 3744:1994. d) Reduction of number of microphone positions. The nine key points may be reduced to five (see figures 1 to 13) if it has been proven that the surface sound pressure level determined in this way on similar pneumatic equipment does not deviate by more than 1,0 dB from the va
43、lue determined using nine key points. NOTE 1 The centre-line of the exhaust of the machine under test shall be equidistant from two measurement positions. If the exhaust impinges directly on a microphone, it distorts the measurement and renders the measurement meaningless. In order to obtain the fou
44、r measurement points in this case, so select them that they are as uniformly spaced as possible around the machine. NOTE 2 Any microphone position between the machine and the reflecting plane shall be omitted. NOTE 3 The overhead microphone position may be omitted for safety purposes. SANS 1470-4:20
45、08 Edition 2 8 NOTE 4 If a machine is normally used both vertically and horizontally, preference shall be given to the position that results in the simplest loading device and acoustic environment. NOTE 5 In order to enable the repeatability of readings, all percussive tools should be tested operati
46、ng vertically, if possible. NOTE 6 It is permissible to rotate the machine with respect to the microphone, instead of moving the microphone with respect to the machine, if loading conditions so demand. 5.3.8 Measurement of the A-weighted sound pressure level (see 7.5 of SANS 3744:1994) Obtain the fo
47、llowing data: a) the A-weighted sound pressure level during operation of the pneumatic machine under test; and b) the A-weighted sound pressure level of the background noise, with the pneumatic machine inoperative. 5.3.9 Calculation of the A-weighted sound power level Calculate the A-weighted sound
48、power level of the pneumatic machine in accordance with clause 8 of SANS 3744:1994. Figure 1 Noise measurement arrangement with microphone positions for sinkers SANS 1470-4:2008 Edition 2 9 NOTE The feed leg is not considered an integral part of the machine for the purposes of determining the geomet
49、ric centre. Figure 2 Noise measurement arrangement with microphone positions for feedleg drills SANS 1470-4:2008 Edition 2 10 Figure 3 Noise measurement arrangement with microphone positions for track-drills NOTE For certain machines sizes, the geometric centre may, of necessity, be at a height other than the 1 m laid down. Figure 4 Noise measurement arrangement with microphone positions for paving-breakers SANS 1470-4:2008 Edition 2 11 Figure 5 Noise measurement arrangement with microphone positions for rivetters Figure 6 Noise measu
