Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.
This standard is developed in accordance with the rules given in GB/T 1.1-2009.
This standard replaces GB/T 14097-1999 Noise limits for small and medium power diesel engines and GB/T 15739-1995 Noise limitation of small gasoline engine.
The following technical changes have been made with respect to GB/T 14097-1999 and GB/T 15739-1995:
——The application scope of the standard has been modified;
——Terms and definitions have been added;
——The noise measurement method has been modified and supplements have been made as to requirements on noise treatment for specific sound sources and the operating conditions of the engine;
——The noise limit equation has been given, and the engine noise grade requirements and the associated rating method have been added;
——The identification of engine noise grade has been added.
This standard was proposed by China Machinery Industry Federation.
This standard is under the jurisdiction of SAC/TC 177 National Technical Committee on Internal Combustion Engines of Standardization Administration of China.
The previous editions of this standard are as follows:
——GBN 259-1986, GB 14097-1993, and GB/T 14097-1999;
——GBN 264-1986, and GB/T 15739-1995.
Reciprocating internal combustion engines - Limit values of emitted noise
1 Scope
This standard specifies the limit values of four sound power levels of noise emitted by the reciprocating internal combustion engines.
This standard is applicable to the reciprocating internal combustion engines as defined in GB/T 21404 (hereinafter referred to as "engines" unless otherwise specified).
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 1859.1 Reciprocating internal combustion engines - Measurement of sound power level using sound pressure - Part 1: Engineering method
GB/T 1859.3 Reciprocating internal combustion engines - Measurement of sound power level using sound pressure - Part 3: Precision methods for hemi-anechoic rooms
GB/T 8170 Rules of rounding off for numerical values & expression and judgement of limiting values
GB/T 21404 Internal combustion engine - Determination and method for the measurement of engine power - General Requirements
3 Terms and definitions
For the purpose of this standard, the following terms and definitions given in GB/T 1859.1, GB/T 1859.3 and GB/T 21404 as well as the following ones apply.
3.1
engine noise grade
classification by engine noise amplitude
?
3.2
engine noise grade 1; ENG1
engines with measured sound power level under all operating conditions less than or equal to the limit value of its corresponding Grade 1 sound power level
3.3
engine noise grade 2; ENG2
engines with measured sound power level under all operating conditions less than or equal to the limit value of its corresponding Grade 2 sound power level, and measured sound power level under at least one operating condition greater than the limit value of its corresponding Grade 1 sound power level
3.4
engine noise grade 3; ENG3
engines with measured sound power level under all operating conditions less than or equal to the limit value of its corresponding Grade 3 sound power level, and measured sound power level under at least one operating condition greater than the limit value of its corresponding Grade 2 sound power level
3.5
engine noise grade 4; ENG4
engines with measured sound power level under at least one operating condition greater than the limit value of its corresponding Grade 3 sound power level
4 Measurement method
4.1 General
Engine noise measurement shall be preferentially carried out in accordance with GB/T 1859.3, or may be carried out in accordance with GB/T 1859.1.
Note: The measurement uncertainty specified in GB/T 1859.3 is smaller than that in GB/T 1859.1 while the engine's working conditions and operating conditions in both of them are exactly the same.
?
4.2 Acoustic treatment of specific sound sources
Acoustic treatment of specific sound sources such as intake noise and exhaust noise of engines, and noise of cooling fan or blower, shall meet those specified in Table 1.
The condensation-cooled engine is a water-cooled engine, but in case of noise measurement, the noise of the cooling fan shall be included.
Table 1 Requirements for acoustic treatment of specific sound sources of engine and values of indexes and constants
S.N. Type Number of cylinders Cooling mode Requirements for acoustic treatment of specific sound sources Index Constant
Combustion air inlet noise Exhaust outlet noise Cooling fan or blower noise α β γ C
dB
1 Spark-
ignition type Single cylinder Water-cooled Included Included Not included 0.75 -1.75 3.5 30.5
2 Air-cooled Included 33.0
3 Multiple cylinders Water-cooled Not included Not included Not included 28.5
4 Air-cooled Included 31.0
5 Compression-
ignition Single cylinder Water-cooled Included Included Not included 2.5 69.5
6 Air-cooled Included 72.0
7 Multiple cylinders Water-cooled Not included Not included Not included 67.5
8 Air-cooled Included 70.0
4.3 Operating conditions
The operating conditions of the engine shall meet the requirements of GB/T 1859.3 (or GB/T 1859.1) during noise measurement. The fixed speed engines and the marine engines shall operate under rated working conditions; engines for other purposes shall operate under a working condition with full load speed characteristic (i.e., external characteristic).
The steady-state measurement shall prevail during operation under the external characteristic condition, and the transient measurement during acceleration/deceleration may also be feasible, but both shall cover the rated speed condition and the condition which is as close to the minimum working speed condition as possible. In case of steady-state measurement, the speed interval shall be selected based on the number series of 400 r/min, 200 r/min, 100 r/min, 50 r/min, 25 r/min, and the number for operating conditions shall be at least 6, and preferably more than 10;in case of transient measurement during acceleration/deceleration, the speed interval of 25 r/min shall prevail, and 50 r/min may also be selected. The period of acceleration/deceleration may also be determined according to the actual service conditions.
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Measurement method
5 Limit values of emitted noise
6 Judgment method
7 Marking
Annex A (Informative) Engine noise grade rating examples
