QC/T 970-2014Technical specifications for passenger car air filters (English PDF)

Introduction

There is no corresponding international standard, foreign standard, national and industry standard with regard to passenger car air filter technical specification. Both domestic and foreign automobile companies and air filter manufacturers have developed technical specifications for their respective enterprises and models. Therefore, there are differences in main properties, technical parameters and test methods. In order to improve the industry standard system of automobile filters, to drive the technological progress of air filters for passenger cars, and to promote trade and communication, it is necessary to formulate this Standard.

The primary function of the air filters for passenger cars is to clean and filter the air entering the engine for combustion. In view of the distinguishing features such as combustion modes of the gasoline engines, diesel engines and gas engines equipped for passenger cars, calorific value and density of fuel, vehicle maintenance cycle, reliability mileage, etc., while maintaining the contents of conventional filter function index, the disparity index was determined for the two properties of full-life filter efficiency and ash storage capacity, respectively.

One of the main functions of the air filters for passenger cars is to eliminate engine intake noise, which has played an important role in reducing the vehicle pass-by noise and noise inside automobile. In the past, the acoustic attenuation performance of the air filters for passenger cars was normally evaluated on the engine bench or full vehicle under prescribed conditions. Test operation is difficult, and the test results affected by the noise sources are lack of comparability. Therefore, the requirements for such technology are almost vacant in relevant domestic standards and product drawings. In this case, it is particularly looking forward to developing adaptive technical requirements and test methods for intake silencing performance, based on the noise elimination characteristics of the passenger car air filter structure. This Standard describes the performance requirements and test methods for sound-transmission loss and surface radiation noise of the air filters for passenger cars, by using white noise as the noise source and adopting the latest measurement principle of two-load method, in order to fill the vacancy and build the technical framework.

With regard to air filters for passenger cars, the vibration fatigue test is mainly used to avoid failure and damage caused by fatigue; the fixed-frequency sinusoidal vibration test is simple to control and easy for test operation, but it cannot reflect the real state of mechanical vibration environment of the air filter.

Consequently, according to the application of air filters in the passenger cars, it is recommended that two test methods of sinusoidal vibration and sinusoidal-random composite vibration, with different requirements for vibration severity, Passenger car air filter technical specification

1 Scope

This Standard specifies the technical requirements, test methods and inspection rules of the air filters for passenger cars (hereinafter referred to as air filters) and the filter elements. Since filter element is the core element of the air filter, all the technical requirements thereof are applicable to the air filter.

This Standard is applicable to the air filters for passenger cars and filter elements with a volume flow of below 900m³/h. Other air filters and filter elements may use this Standard for reference.

2 Normative references

The following documents are essential to the application of this document. For dated references, only the editions with the dates indicated are applicable to this document. For undated references, only the latest editions (including all the amendments) are applicable to this document.

GB/T 2298-1991 Mechanical vibration and shock - Terminology

GB/T 2423.56-2006 / IEC 60068-2-64:1993 Environmental testing for electric and electronic products - Part 56. Test methods - Test Fh. Vibration, broad-band random (digital control) and guidance

GB/T 2423.58-2008 / IEC 60068-2-80:2005 Environmental testing for electric and electronic products - Part 58. Test methods - Test Fi. Vibration - Mixed mode

GB 3240 Preferred frequencies for the acoustical measurement

GB/T 3241-1998 Octave-band and fractional-octave-band filters

GB/T 3730.1-2001 Motor vehicles and trailers - Types - Terms and definitions

GB/T 3785.1-2010 Electroacoustics - Sound level meters - Part 1. Specifications

GB/T 3947-1996 Acoustical terminology

GB/T 4760-1995 Acoustics - Measurement procedure for silencers The sealing parts of the air filter shall be sealed in a reliable manner. Overhaul shall be performed immediately upon the completion of the filter efficiency test or ash storage capacity test. The sealing parts of the air filter shall have no trace of ash leakage.

4 Requirements

4.2.10 Isolation noise performance of the air filter.

Within the center frequency range of (50 ~ 10000) Hz at 1/3 octave, the radiation noise attenuation value on the upper surface of the air filter shall not be less than 35dB.

4.2.11 Sound-transmission loss of the air filter. […]