ISO/TC 39/SC 6 - Noise of machine tools

ISO 8525:2008 describes, with reference to ISO 230-5, the mechanical and acoustical specifications necessary for a reproducible test method for the determination of airborne noise emitted by metal-cutting machines and related auxiliary equipment. The purpose is to facilitate the obtention of comparable test results on the noise emission of similar machines. The results of the tests can be used for comparison, acceptance, maintenance or any other purpose. ISO 8525:2008 specifies, in particular, operating conditions for the measurement of noise emitted by metal cutting machines excluding any cutting process. These operating conditions are strictly the same for the determination of both sound power levels and emission sound pressure levels at specified positions. ISO 8525:2008 applies to all kinds of turning machines and all kinds of milling machines.

1.1 General This part of ISO 230 specifies methods for testing the noise of stationary floor-mounted machine tools and related auxiliary equipment directly on the shop floor. The purpose of the measurements is to obtain noise-emission data for machine tools. The data obtained may be used for the purpose of declaration and verification of airborne noise emission from machine tools as specified in ISO 4871, and also for the comparison of the performance of different units of a given family of machine tools or equipment, under defined environmental conditions and standardized mounting and operating conditions. For the purposes of this part of ISO 230, "auxiliary equipment" means hydraulic power packs, chip conveyors, coolant-oil mist extractors, heat exchangers, refrigerators, etc. Noise emitted by centrally operated auxiliary equipment, connected to several machine tools, shall be considered as background noise. General instructions are given for the installation and operation of the machine under test and for the choice of microphone positions for the work station and for other specified positions. More detailed instructions can be found in specific noise-test standards for individual types of machine tools. Clause 11 specifies a method for measuring the emission sound pressure levels at work stations and at other specified positions in the vicinity of a machine tool. This method follows the methods specified in ISO 11202 and ISO 11204. Clause 12 specifies a method for measuring the sound pressure levels on a measurement surface enveloping the machine tool and for calculating the sound power level produced by the machine tool. This method follows the methods specified in ISO 3744 and ISO 3746. The determination of the sound power level on the basis of the intensity method (ISO 9614 and ISO 9614-2) is not dealt with in this part of ISO 230. 1.2 Types of noise and noise sources The methods specified in this part of ISO 230 are suitable for all types of noise emitted by machine tools. This part of ISO 230 is applicable to machine tools of any type and size, including devices, components and subassemblies. NOTE Measurements according to this part of ISO 230 may be impracticable for very tall or very long machine tools, such as transfer lines. 1.3 Test environment The test environment that is applicable for measurements made in accordance with this part of ISO 230 is generally located indoors, with one or more reflecting planes present, meeting specified requirements, as described in clauses 11 and 12, respectively in 11.4.2 and in clause 12.3.2. 1.4 Accuracy grades Individual values of emission sound pressure levels at a fixed position and of the sound power level of a machine tool determined in accordance with the procedures given in this part of ISO 230 are likely to differ from the true values by an amount within the range of the respective measurement uncertainties. The uncertainties in measurements of emission sound pressure levels and in determinations of the sound power level arise from several factors which affect the results, some associated with environmental conditions at the test site and others with experimental techniques. This part of ISO 230 deals with methods to determine the emission sound pressure levels and the emission sound power level, where the results meet grade 2 accuracy (engineering method) and grade 3 accuracy (survey method). Because of its higher accuracy, grade 2 should be achieved whenever possible. Specific information on measurement uncertainties is given in clause 7. Although grade 2 accuracy (engineering) is preferred, grade 3 accuracy (survey) is acceptable for noise declaration and most other purposes. In this part of ISO 230, only the determination of grade 3 is described completely. For grade 2, ISO 3744 and ISO 11204 shall also be used.

Describes, together with basic noise emission International Standards, the mechanical and acoustical specifications necessary for a reproducible test method for the airborne noise emitted by woodworking machines. Specifies standard operating conditions and microphone positions for the measurement on 19 types of woodworking machines. The existence of special-purpose machines, for which such standard operating conditions cannot be specified, is acknowledged. Additional types will be covered in future editions.