However, for the Chinese market, single pump is almost a perfect choice in the current situation. It has very few changes to the engine and only makes changes in the oil system. Moreover, the uni-pumps are much more tolerant of oil quality than high pressure common rail pump systems. Due to the fact that it has followed the oil refining model of the former Soviet Union, China’s diesel fuel has a very high sulphur content in addition to high impurities. At present, Europe can achieve a sulfur content of 10 to 15 units per million unit (10 ~ 15PPM), the average level in China only 300PPM, Beijing's best level is 50PPM.
The improvement of automobile emission standards is nothing more than the application of new technologies in the three stages of intake, combustion and exhaust gas treatment. However, the combination of technologies brought by these three links has made it impossible for China, a country that follows and imitates, to choose. This is also why China's automobile emission standard selection is closer to European standards, but the development of domestic diesel engines has lagged behind.
The advantages of the single-unit pump system in terms of cost and performance are highlighted on heavy-duty trucks where customers are advised to use single pump systems. From the cost point of view, when the domestic engine is upgraded from Euro II to Euro III , if a single pump is used, the change to the engine is very small. When you upgrade from Euro III to Euro IV , this structure remains unchanged, except that the mechanical injectors in the Euro III system were changed to Delphi's electronically controlled injectors. Under the overall adjustment of the engine structure, Euro IV emission levels can be achieved . In terms of performance, the pressure of the single pump is currently used in the country to reach a pressure of 2480 bar . When upgrading to Euro IV , in a two-valve system, this pressure can reach 2580bar . And the theoretical design principle of the single pump can cause gradual and gradually increasing injection pressure curve, which is an ideal curve for the engine. At the same time, the production properties of a common rail pump similar to that of a high pressure common rail pump are used on the single pump to optimize the performance of the entire system. In terms of oil supply control, if a double-valve system is used, not only pressure can be controlled but also injection can be controlled, and multiple injections can be used. Its standard can reach Euro IV or Euro V capabilities. Delphi's double-valve system is currently in mass production in Europe, supplying Euro IV engines, and Euro V engines are doing related development work. Another advantage of the unibody pump system is its reliability and longevity, and these properties have been proven in Europe and North America over more than a decade or even 15 years of actual use time, as evidenced by the use of millions of complete vehicles. Delphi's single pump system can ensure its emission levels and fuel consumption levels throughout the entire engine life. At present, this very hardened, very reliable performance and service life are still further improved. So from Delphi's point of view, in terms of technology, it is believed that by 2010 , all European and North American heavy-vehicle manufacturers will use monobloc pump and pump nozzle technology. Delphi is also developing a new system required by the new emissions regulations in 2010 .
High-pressure common rail technology is not unique to BOSCH . In fact, Delphi, Siemens, and Denso all have high-pressure common rail technology. Delphi and Siemens have good capabilities in high-pressure common rail technology, but Siemens currently has no force in China. Delphi China The strategy for heavy-duty diesel engines is to push the single-pump, and Japan Denso is now cooperating with Sichai, but from a technical point of view, the high-pressure common rail will be the final direction. In 2004 , the single-pumped Euro 3 was actually chopping firewood. Both Shanghe Diesel and Shangchai have been introduced, but in the final production line, the final decision direction is still to choose high-pressure common rail. Jinan Heavy Duty Truck to the current two production plants are producing WD615, temporarily estimated there is no extra funds on the high pressure common rail production line, Therefore, after the European heavy truck Jinan Road 3 of Delphi and should co-production of Euro 3 unit pump.
Tungsten Carbide Rings,Carbide Cold Rolling Rings,Tungsten Carbide Cold Rolling Rings
Non-Standard Carbide Co., Ltd. , http://www.nsnonscarbide.com