Automobile Inspection Technology

Chapter 3 Introduction (2)
② allowable value.If the measured value of the detection parameter is within this value range, the technical condition of the diagnostic object has changed, but it is still normal, and it can continue to run without repair, but it should be maintained on time.If this value is exceeded, it is barely allowed, but repairs should be arranged in time.Otherwise, the car will run sick, the failure rate will increase, and it may not be able to drive for the next detection cycle.

③ limit value.After the measured value of the detection parameter exceeds this value, the technical condition of the diagnostic object will seriously deteriorate, the power, economy and exhaust purification performance of the car will be greatly reduced, the driving safety will not be guaranteed, the related parts will be seriously worn, and even mechanical accidents may occur .Therefore, the car must be stopped immediately for repairs, otherwise it will cause greater losses.

It can be seen that by testing the car, when the measured value of the detected parameter is within the allowable range, the car can continue to run; when the measured value of the detected parameter exceeds the limit value, it must stop running and enter the factory for repair.Therefore, by comparing the measured value of the detected parameter with the standard value of the detected parameter, the technical condition of the vehicle can be known, and thus it can be determined whether it should be maintained or repaired.

The establishment of vehicle inspection parameter standards is a complicated process, which is generally completed by statistical methods, empirical methods, experimental methods or theoretical calculation methods.Statistical methods are often used to formulate testing standards that take into account various factors such as technology, economy, and safety by finding out the distribution of testing parameters for a considerable number of vehicles or assemblies and components under normal conditions.The detection standards obtained in this way generally include: average parameter standard (the parameter is centered on a value, and the standard is reached within a certain range), the detection standard of the upper limit (the measurement parameter must be less than this standard value to be considered normal) and the detection of the lower limit Standard (the measurement parameter must be greater than this standard value to be considered normal).

The diagnostic criteria formulated must be tried out for a period of time, and can only be finalized and included in the criteria after revision.And with the improvement of production technology and the development of social economy, the testing standards need to be continuously revised and improved.

3. Vehicle inspection cycle

The detection cycle is the interval period of car diagnosis, represented by driving mileage or driving time.The optimal detection cycle is the detection cycle that can ensure the highest vehicle integrity rate and consume the least cost.

Determining the best inspection cycle should not only make the vehicle run in a trouble-free state, but also minimize the cost of "regular inspection, mandatory maintenance, and repair according to the situation" in my country's maintenance system, so it is necessary to do a good job on "regular" .

To formulate the optimal detection cycle, the following factors are mainly considered:

(1) The technical condition of the vehicle The optimal detection period specified will not be the same when the vehicle is old or new, mileage, technical condition level, performance, structural characteristics, failure pattern, and quality of accessories.For new cars or overhauled cars, cars with less mileage, and cars with a technical condition grade of one, the optimal detection cycle should be long, otherwise it should be short.

(2) Conditions of use of automobiles, which include conditions such as weather conditions, road conditions, loading conditions, driving skills, whether tow or not, fuel quality, etc.For cars with bad weather, extremely poor road conditions, frequent overloading, poor driving skills, trailer driving, and unguaranteed fuel quality, the optimal detection cycle should be short, and vice versa.

(3) Expenses It includes the expenses of detection and diagnosis, maintenance and repair, and stop loss.If the cost of detection, diagnosis and maintenance is reduced, the optimal detection cycle should be extended, but the loss cost of the car due to failure will increase; if the cost of stop loss is lower, the optimal detection cycle should be shortened, but The cost of detection, diagnosis, maintenance and repair has increased.

[-]. Relevant regulations and standards for vehicle testing

In order to ensure traffic safety, reduce environmental pollution and ensure that the vehicles in use are in good technical condition, the national public security, transportation, environmental protection and other departments have successively issued a number of laws, regulations and relevant standards to strictly manage the vehicles in use.

1. Relevant laws and regulations
The relevant laws and regulations promulgated by the state and various departments in recent years mainly include the following:
The 1987 "Law of the People's Republic of China on the Prevention and Control of Atmospheric Pollution" proposed the supervision and management of air pollution by motor vehicles and ships.

The "Regulations of the People's Republic of China on Road Traffic Management" issued in 1988 put forward the requirements for motor vehicles to drive on the road.

In 1989, the Ministry of Public Security issued Order No. 2 "Administrative Measures for Motor Vehicle Safety Technology Inspection Stations", which proposed the functions and management methods that safety inspection stations should have.

In 1990, the Ministry of Communications issued Order No. 13 "Regulations on Vehicle Technology Management in the Automobile Transport Industry", which put forward the requirements for the technical status of transport vehicles, technical grades, and conditions for inspection, maintenance, and scrapping of vehicles.

On April 1991, 4, the Ministry of Communications issued Order No. 23 "Administrative Measures for Vehicle Comprehensive Performance Testing Stations in the Automobile Transportation Industry", which mainly stipulated the functions and levels of comprehensive performance testing stations established by the transportation department.

2. Relevant standards
The main standards promulgated by the state and various departments are as follows:

The national standard "Technical Conditions for Motor Vehicle Safety Testing Equipment Appraisal" (GB/T2001-11798.1-11798.6), revised in 2001, proposes a method for calibrating safety testing equipment.

1995年《汽车技术等级评定标准》(JT/T198-1995)与《汽车技术等级评定的检测方法》(丁/丁199一1995)，根据技术状况将汽车分为一、二、三级，并提出了评定等级的检测方法。2004年两标准合并为JT7T198-2004《营运车辆技术等级划分和评定要求》。

1999年的国家标准《汽车综合性能检测站通用技术条件》(GB/T17993-1999)，是依据交通部1990年第13号令《汽车运输业车辆技术管理规定》、1991年第29号令《汽车运输业车辆综合性能检测站管理办法》以及1998年第2号令《道路运输车辆维护管理规定》中提出的检测站的主要任务、等级、职能和检测条件等要求制定的。该标准明确规定了汽车综合性能检测站的检测项目、设备、厂房、人员、场地以及管理制度等条件。

国家质量技术监督局于2000年12月28日发布了强制性国家标准《在用汽车排气污染物限值及测试方法KGB18285-2000)。2001年颁布的GB18352.1一2001轻型汽车污染物排放限值及测量方法（I)和GB18352.2-2001轻型汽车污染物排放限值及测量方法（II)，2005年出台的机动轻型汽车号排放标准将于2007年7月1日起实施，该标准将代替现行的轻型汽车n号排放标准等九项机动车排放和检测方法标准。

2001年12月13日发布、2002年8月1日实施的国家标准《营运车辆综合性能要求和检验方法KGB18565-2001)，是依据国家有关安全、节能、环保等方面的政策、法规和我国汽车运输车辆技术管理有关规定，并参照先进国家相关标准制定的。该标准大量引用国家标准《机动车运行安全技术条件KGB7258-1997)及其相关标准，所以也具有与GB7258-1997类似的框架结构。其中在排气污染物限值和测量方法方面，则引用了国家标准GB18285-2000，后者是参考了较先进的国际标准制定的。

The national standard "Technical Conditions for Motor Vehicle Operation Safety KGB2004-12" issued in December 7258 was revised based on the same standard issued in 2004.This is an authoritative standard for motor vehicle inspection and the most basic technical regulations for motor vehicle safety technology management in my country; it is the main technology for new car registration, regular inspection of in-use vehicles, accident vehicle inspection and other safety technology inspections by traffic management departments of public security organs It is also one of the important technical basis for the mandatory inspection of new motor vehicles in my country, the factory inspection of new vehicles and the inspection of imported motor vehicles.

In May 2008, the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China and the Standardization Administration of China jointly issued the "Motor Vehicle Safety Technical Inspection Items and Methods" (GB5-2009), which was implemented on June 6, 1.With reference to the newly added technical requirements of GB21861-2008, combined with the actual needs of my country's road traffic safety management, according to the current road traffic safety laws and regulations such as the "Road Traffic Safety Law of the People's Republic of China" and its implementation regulations, on the basis of GA7258-2004 National standards for motor vehicle safety technical inspection items and methods formulated on theClarify the motor vehicle safety technical inspection items, refine the inspection methods and audit requirements, in order to further improve the scientificity and operability of the standards.This standard applies to motor vehicle safety technical inspection agencies conducting safety technical inspections of motor vehicles running on roads in my country, and this standard is also applicable to import and export motor vehicle inspection agencies conducting safety technical inspections of motor vehicles in traffic.This standard can be referred to when conducting safety technical inspections of motor vehicles approved by relevant departments for actual road tests.

3. Relevant management system
Carrying out regular inspection and timely maintenance and repairs on the vehicles in use is an effective management system to ensure that the vehicles in use are in good technical condition, and has been adopted by many countries.

my country's public security and traffic management departments implement an annual inspection system for in-use vehicles.The traffic management department mainly conducts regular inspection and maintenance management on the operating vehicles in use.In addition, the traffic or environmental protection departments of many cities often conduct spot checks on the exhaust emissions of vehicles driving on the road.

The I/M (inspection/maintenance, inspection/maintenance) system originated in the United States in the 20s. It is a system in which developed industrial countries and regions in the world conduct mandatory regular inspections of in-use vehicles and mandatory repairs of failed vehicles. .The traditional car repair and maintenance process does not pay much attention to the internal relationship between the various systems of the engine, so it cannot adjust the performance of the engine to the best condition. The core content of the I/M system is to adjust the data of the important parts of the automobile engine. The operation of the engine reaches the best state, so as to effectively control the fuel consumption and reduce the exhaust pollution. The I/M system adopts a centralized testing method, forcing vehicles in use to be tested at special emission testing stations. The implementation of I/M has enabled the vehicles in use in the United States to meet the strict environmental protection requirements of the United States, and at the same time greatly reduced the occurrence of vehicle failures. In the decade from 80 to 1980, the number of auto repair shops in the United States decreased by 1990, and the number of gas stations equipped with auto repair decreased by 31.5. From 5000 to 1985, the number of related car maintenance centers increased by 1995.

After my country joined the WTO, the number of cars increased sharply. By 2008, the number of cars in my country had exceeded 6400 million. Vehicle exhaust emissions have become an important source of air pollution in large and medium-sized cities.On the basis of absorbing advanced foreign experience, my country has restricted the exhaust pollution by strengthening the maintenance and management system of automobile inspection.At present, my country has generally implemented national emission standards for motor vehicles, and Beijing and Shanghai have implemented national emission standards ahead of schedule.On the basis of absorbing foreign advanced management experience, cities such as Beijing and Shanghai research and test the I/M system suitable for my country, build authoritative I station (testing station) and M station (maintenance station) to implement regular inspections, mandatory maintenance and maintenance. The monitoring and evaluation management system has achieved good results.

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