Due to the physicochemical properties of diesel, diesel engines must be equipped with more complex injection systems. Since the first diesel engine was invented in 1892 by Diesel in 1892, the diesel fuel injection system is mechanical, and the oil pump nozzle is the two main key components in this system. They have a decisive influence on key indicators such as the efficiency of diesel combustion, emission levels and power performance. Within a certain range, the oil pump nozzle has become the name of the diesel fuel injection system and is called the "heart of the heart of the car." This habit even extends to the EFI era.
Due to its technical complexity and difficult processing, and relatively independent of other parts of the engine, the oil pump nozzle equipment is often produced by some professional companies and gradually forms a relatively independent branch industry.
Until more than a decade ago, the performance of diesel engines was still unsatisfactory, with huge noise and smoky smoke. The diesel locomotives have always been considered as a typical example of industrial civilization. It is because of the high noise, vibration, emission pollution and other defects, so the diesel engine has long been rarely favored by the car, although it has better dynamic performance.
Two major motive forces of the technological revolution
In the last 10 years, a major technological change has dramatically changed the performance of diesel engines.
The first impetus for technological change comes from changes in market demand under government control. With heightened awareness of environmental protection, from 1982 to 1998, the U.S. government’s response to the emission of nitrogen oxides and particulates for automotive diesel engines was reduced three times; European emission regulations have also rapidly progressed to Europe II from European Standard I, which was implemented in 1993. Euro III standard, the current passenger car has begun to implement the Euro IV standard, and commercial vehicles in January 2006 began to implement the Euro IV standard. National laws and regulations have exerted increasing pressure on the development of diesel engines, forcing companies to seek technological solutions.
The second impetus for technological change comes from changes in the supply of new technologies. After entering the 1980s, great progress has been made in electronic technology and precision machining technology, especially the addition of electromagnetic control means. The new electronically controlled injection system has completely replaced the traditional mechanical fuel injection system. It is generally believed that the improved mechanically controlled injection system can meet the Euro I and Euro II emission standards at most, but if it is to achieve Euro III or even more stringent emission standards, it must adopt the electronically controlled fuel injection system. With the more precise control methods, the vibration and noise of the diesel engine are greatly reduced, and the comfort is greatly improved, which in turn makes the advantages of the diesel engine such as good economy and large power fully manifest.
Faced with the pressure of market demand and important technological breakthroughs, the relevant international companies have made a lot of investment in the development of a new generation of fuel injection systems. In the late 1980s and 1990s, Germany's Bosch, Japan's Zexel, and US-based Stanadyne launched electronically controlled diesel injection systems based on different design concepts. Before and after 1987, the electronically controlled high pressure common rail system first put forward by Fiat gradually became a mainstream direction. From around 1993, Bosch bought patents from Fiat and began the research and development of common rail systems. Electronically controlled common rail system is the key to solve the problem of diesel engine emissions and further improve performance.
The diesel engine trend of cars
The revolution in electronically controlled injection systems has greatly expanded the range of applications for diesel engines. Due to the emergence of a series of fuel injection technologies such as the electronically controlled high pressure common rail, the noise of the diesel engine has been greatly reduced, and the comfort has greatly improved. In addition, the inherent advantage of the diesel engine in terms of energy efficiency, the original car industry dominated by the gasoline engine has apparently appeared "Dieselization" trends, especially in Europe. With the continuous introduction of diesel-equipped car products by major international automobile manufacturers, this trend has been accelerated.
At present, 90% of the automobiles with a total mass of more than 3.5 tons are diesel engines. In 2004, 48.2% of European cars were produced with diesel engines. BMW's diesel engine car ratio has reached 60%, while Mercedes-Benz new models have also improved the proportion of diesel engines. At present, among domestically produced cars, only Jetta, Bora and Audi have diesel engine products, but none of them are the most advanced technologies in the world.