National III Implementation of Heavy Truck Technology Lines Is Increasingly Fierce
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After several years of discussion and revision, on July 1, 2008, the third phase of the motor vehicle country's emission standards (ie, Euro III emission standards) was formally implemented. New cars that did not meet the National III standard will be completely suspended from sales and registration. .
As early as before and after the implementation of the National III Standard, the industry’s debate on what kind of technical route China's State III should adopt has not stopped. The 2008 China Commercial Vehicles III Technology Summit Forum jointly sponsored by the Research Department of the International Cooperation Center of the National Development and Reform Commission, the Automotive Engineering Development Research Institute of Tsinghua University, and the “Car Watch†magazine has pushed the intensity of this debate to a climax.
Technical dispute
With the changes in standards, China’s heavy-duty truck industry, which has been developing rapidly in recent years, has finally ushered in an earth-shaking revolution: On the one hand, the heavy-duty truck industry has ushered in an opportunity for industrial upgrading; on the other hand, around different emission standards, The heavy truck industry launched a game on which technology route to use.
This 2008 China Commercial Vehicles III Technology Summit Forum undoubtedly became a competitive platform for heavy truck companies to demonstrate their technology.
For China's heavy-duty truck industry, the implementation of the National III standard will comprehensively test the domestic auto companies' resilience and technical reserves, which is a huge impact on domestic auto companies. At present, there are mainly three kinds of technologies that can meet the national III emission standards. One is the electronically controlled high pressure common rail, the second is the electronically controlled pump nozzle technology, and the third is the electronically controlled monomer pump technology. These technologies are mainstream technologies. In addition, there is a non-mainstream technology of H-pump (mechanical pump or in-line pump) + EGR that has been eliminated internationally.
According to participating experts attending the summit forum, currently, in these several technical routes, electronically controlled high pressure common rail technology has occupied an absolute “overlord†status, and almost all heavy truck manufacturers in China have adopted the process of implementing State III. This is the technology. Most of the enterprises did not adopt EGR technology when they upgraded from State II to State III, with the exception of China National Heavy Duty Truck.
According to experts, the so-called electronically controlled high pressure common rail technology is in the common rail pressure accumulator injection system. The ECU (equivalent to the engine's computer) receives the signal from each sensor and uses the electromagnetic valve on the injector to allow Diesel fuel injection with correct injection pressure at the correct injection point to ensure the best combustion ratio, atomization and optimal ignition time of the diesel engine, as well as good economy and minimum emissions.
The mechanical pump + EGR technology is the technology of the 1980s. Its working principle is to add an exhaust gas cooler and an electronically controlled EGR valve. The technology has high fuel consumption and poor consistency, and cannot meet higher emission requirements. The biggest drawback is that it cannot take into account both fuel economy and emission targets. That is, when the emission requirements are met, fuel consumption will be 15% higher, so they are soon abroad. The company gave up.
Many domestic engine experts believe that “electronic control†is a sign of the State III heavy truck and is the mainstream of more advanced emission technologies such as the State IV in the future. This technology can effectively reduce fuel consumption and reduce user costs.
The mechanical pump + EGR working principle is based on the State II mechanical pump, the use of electromagnets to control the mechanical pump rack, the oil valve, made simple electronic fuel injection pump plus EGR exhaust gas reprocessing system to reduce emissions. Although the technology is cheap, it has repeatedly been questioned by people in the industry because its mechanical pump cannot accurately inject fuel, resulting in high fuel consumption.
Although most domestic companies and experts are optimistic about electronically controlled high pressure common rail technology, since the beginning of this year, in the context of the imminent implementation of the National III standard, discussions on the heavy truck industry around electronically controlled high pressure common rail technology and EGR technology have been in full swing. In progress.
Some experts worry that EGR technology was only adopted by a few foreign companies before, and its technical performance has not yet been fully tested by the market. Some experts also frankly stated that when the State III upgrades to the State IV, the high pressure common rail technology has more room for technological upgrading.
Experts in the industry believe that in developed countries, the technical route of EGR and high-pressure common rail has been adopted in the implementation of Euro III, but at the time of Euro III to Euro IV upgrade, it is difficult to raise the emission standard by relying solely on EGR, but the high pressure Common rail routes can do so, so foreign mainstream companies are using high pressure common rail technology to achieve Europe III.
However, Yang Fuyuan, a professor at Tsinghua University and a diesel emission expert, believes that if the engine's emission requirements are strictly complied with and the conformity requirements can be met, what systems are acceptable. The dispute between high pressure common rail technology and EGR technology is a problem of market competition.
Why is EGR frequently questioned?
There are several technical routes that the engine can choose from in order to achieve the national III emission standard. What kind of technical route is best for China? What kind of technology line is more sustainable in the future upgrade of emission standards? How to ensure that products produced through different technical routes can truly meet the national III standard? How to protect the interests of enterprises that seriously implement the National III standard? This has become a major issue for domestic heavy truck companies.
Why the EGR technology has still been questioned by many people in the industry under the premise that the country has clearly adopted several technologies including electronically controlled high pressure common rail technology that can meet the national III emission standards?
Wang Yuanji, general manager of Wang's Witt EFI Co., Ltd. has worked abroad for many years. He said that in 1998, the United States began to implement the EPA 1 998 standard (equivalent to Euro III). In order to meet the North American EPA 1998 emission standard, the United States’ heavy truck company Including Caterpillar and Cummins, they adopted the EGR technology that they believe is technically feasible and economical. However, this resulted in poor reliability of the system and maintenance of the engine. For a long time, these problems have plagued US engine manufacturers. In addition, by doing a lot of reliability experiments, and finally to use them, they found that the service costs are very high, and the most critical EGR in them is very easy to get stuck, the coolant is often blocked, and the system must get to the factory if something goes wrong. Overhaul.
Zhu Yuanxian said that some practices adopted by US heavy-duty diesel engine manufacturers to meet mandatory emission standards 10 years ago are worthy of domestic enterprises' reference.
According to Zhu Yuanxian, on October 22, 1998, the U.S. Department of Justice and the Environmental Protection Agency jointly announced that they were involved in seven North American operations including Caterpillar, Cummins, Detroit Diesel, Mike Trucks, Polaris-Universal Trucks, Renault Trucks, and Volvo Trucks. Heavy-duty diesel manufacturers reached an out-of-court settlement agreement, and seven companies paid more than one billion U.S. dollars for their excess emission commitments, including a fine of 83.4 million U.S. dollars.
The US Environmental Protection Agency has determined that the seven diesel engine companies have installed certain programs on diesel engines since the end of the 1980s, that is, certain software programs that can change the engine emission control system under freeway driving conditions. With this software program, the engine can meet emission requirements during testing, and the emission control system can be shut off once the vehicle enters a normal high-speed driving state.
The US Environmental Protection Agency discovered the above problems in 1997 and began a large-scale investigation.
The US Environmental Protection Agency ruled that although these diesel engines can meet emission standards under test conditions, the emission of nitrogen oxides after turning off the emission control device on highways exceeds the upper limit of the regulatory requirements by three times.
In view of this, the U.S. Environmental Protection Agency calculated the weight of pollutants that exceeded the standard for the above-mentioned seven diesel engine manufacturers based on the number of engine sales and the size of the emissions, and penalized the amount of punishment.
The US EPA also requires these companies to invest at least US$850 million in the production of a new generation of low-emission diesel engines, and invest an additional US$195 million in the development of new emission control technologies.
Foreign Technology Routes vs. China's National Conditions Although the industry's disputes have been intensified, Zhu Yuanxian believes that only the technology line that suits the Chinese market will have vitality.
Zhu Yuanxian believes that under the requirements of meeting State III emissions, China's situation is somewhat different from that of foreign countries. The United States upgraded its mechanical pump to an electric jet pump more than a decade ago. At that time, there was no change in its price. Now in China, regardless of how to increase production efficiency and how to plan carefully, this price is always difficult to reach the current level of mechanical pumps. Only the purchase cost of the sensor is more than two thousand dollars higher than the mechanical pump. Therefore, we must fully consider the situation in the Chinese market.
Zhu Yuanxian believes that EGR technology can meet Euro III emission, but in the case of using EGR technology, due to the decrease of effective air-fuel ratio, EGR technology has the effect of delaying combustion. Domestic diesel vehicles generally have such a problem that black smoke is emitted when the high-speed road accelerates. If the use of EGR air-fuels deteriorates further, black smoke will become more serious.
For the reliability of the EGR system, Zhu Yuanxian proposed static cyclic monitoring on the engine using the system, install an OB D system (auto-car diagnostic system) on this system to monitor whether EGR is working properly.
Yang Songlin of Dongfeng Motor Company's marketing department stated that Dongfeng Motor currently uses two technical routes, one is a high pressure common rail, and the other is a single pump. The heavy trucks of these two technical routes have been brought to the market and reflect a good response.
Regarding the question raised by reporters on why Dongfeng Motor did not adopt EGR technology, Yang Songlin stated that the company's decision-making committee after a lot of argumentation and research found that the EGR system has problems of consistency and poor reliability, and this aspect has not yet matured. Inspection. Therefore, when selecting the technology route, the mature technology that Europe had applied 10 years ago was adopted.
According to report, the domestic mainstream engine manufacturer Weichai had invited foreign companies to help design the engine several years ago. The foreign company believed that the use of EGR technology was more in line with China’s national conditions, but later, the Weichai shares were eventually adopted. High pressure common rail technology.
Why do you choose between these two technical routes? Li Shaohua, assistant to president of Weichai Co., Ltd., believes that high pressure common rail technology has proven to be a mature and advanced technology in Europe and the United States. Although the heavy truck with high-pressure common rail technology is priced at about 20,000 yuan more than the EGR heavy truck in terms of vehicle, the high pressure common rail technology saves at least 5% to 7% of the mechanical pump or EGR technology in terms of fuel consumption. The service fee will be reduced by 60%, and the fuel consumption per hundred kilometers will save at least 2 liters. From the perspective of cost reduction, high pressure common rail technology can be completely accepted by the market and users.
Experts attending this forum generally believe that customers' commercial vehicles are used to make money. Therefore, what they are most concerned about is cost. There are two major areas where users consider the cost of car purchases. One is the fixed cost of one-time investment, and the other is the cost of after-sales costs, fuel costs, and other costs. Therefore, companies should be responsible for the user's attitude, the products launched must be able to withstand the test of the market in various circumstances.
View related topics: State III standard commercial vehicle companies usher in new challenges
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