The main supporting pieces of machinery have power components, transmission components, hydraulic components and electrical components. Basically, the current construction machinery, power components are used internal combustion diesel engine (the engine); transmission sub-mechanical transmission, hydraulic mechanical transmission, hydrostatic transmission, electric transmission and so on. But most used construction machinery, the most common for the hydraulic mechanical transmission and hydrostatic transmission. The transmission system also includes the drive shaft, drive bridges. Hydrostatic drive a variety of structural forms, and some have drive shaft, drive axle, and some did not, as the case may be; hydraulic components are tanks, pumps, valves, seals and hydraulic accessories. Hydrostatic components of the pump (mainly variable pump), motor (variable and quantitative), and the corresponding reducer; electrical components prior to the impact of construction machinery is also not large, the first electrical system of construction machinery, mainly starting circuit and lighting circuits, systems and components are very simple and can start dragging start, do not work during the day light, so this system broke down two circuits can barely work. However, machinery development today, the electrical system and electrical engineering components has become a critical part of the machinery can be said that the vast majority of today's construction machinery, electrical system broke down simply can not work, and some even move an inch, equal to one iron and steel scrap heap. Therefore, electrical system, electrical components is currently the most important engineering machinery fittings most critical one. The main components in addition to traditional electrical components, there are a variety of sensors, a variety of control components and microprocessor and so on. Here the major international engineering machinery fittings such basic situation and development trends to talk about the view.1 Foreign principal component parts of construction machinery BasicConstruction machinery in foreign countries, most of the major component parts to produce a long history and mature technology, an adequate supply of high concentration of production, brand prominence. Supporting the development of pieces of the development with the development of the host, while supporting the pieces of their own development, in turn, promote the development of the host. Component parts of construction machinery in foreign countries, the development of the situation is better than the host developments.1.1 The component parts of construction machinery in foreign countries, the development of the situation is betterForeign construction machinery in recent years there is a trend, the host manufacturing enterprises gradually to the direction of assembly, parts and gradually by the supplier to provide. Example, hosts the world's most powerful U.S. manufacturer Caterpillar (Caterpillar), Case (Case), Japan's Komatsu (Komatsu), Sweden's Volvo (Volvo), the world on these large-scale construction machinery manufacturing enterprise, its component parts is also very strong supporting capacity, and their component parts to the number of foreign spouses is also a considerable increase in the year, a number of small and medium enterprises especially in construction machinery, auxiliary equipment, parts and components manufacturers to gradually mainly to provide . This has several advantages, the host enterprise can concentrate on their main products to prepare and reduce the component parts to fully borne by the host enterprise's own risk, and supporting documents be stronger for larger enterprises, have the ability to rapidly improve the matching pieces quality, technical level, while the host can provide more new products that make it easy for the host product development. Foreign construction machinery enterprises in 1988 850 billion in sales since, basically have not changed much, and contrary to ancillary pieces of the years from 150 billion dollars, up to 1000 billion U.S. dollars, an increase is quite large. Therefore, foreign engineering machinery fittings over the years has been rapid development.1.2 The foreign construction machinery component parts produce a long history and mature technology, full range, can meet the needs of various engineering machinery dealsMany foreign construction machinery enterprises are the main component parts for 50 years, or even 100 years of history, are relatively large-scale enterprises, technology is very mature, the variety is also very complete, almost everything. Such as the current production of seals and the world's largest enterprise shock absorber, Germany, Florentino Eden Baker (Freudenberg), founded in 1849, production of seals and damper than 100 years of history, its varieties of everything, from the Technically, the varieties can meet the hydraulic industry seals and sealing technology requirements. Also continue to introduce new materials and new seal sealing the structure, hydraulic sealing technology continues to promote to a higher level of technology development. The world's largest engine manufacturer in the large U.S. Cummins (Cummins) engine manufacturing company, founded in 1919, but also almost 100 years of history. 37.3kW (50 hp) or more of the diesel engine can be full for a variety of construction machinery, and even all the necessary machinery and auxiliary diesel power, it is technically possible to fully meet the most demanding Euro II, Euro III emission standards, even to Europe IV, Euro V emission standards.In the field of fluid products, the world's largest fluid products (mainly hydraulic parts, seals and hydraulic attachments, etc.) manufacturing companies, the United States Parker (Parket), founded in 1918, there are nearly 100 years of history, full range, high-tech level of hydraulic parts, hydraulic seals, and all attachments. The world's largest hydraulic system for static variable hydraulic components manufacturer, the German Doctor - Rexroth Corporation, more than 200 years of history, since 1953 a comprehensive manufacturer of hydraulic components, there are more than 50 years of history. The most unique product is used for the variable hydrostatic transmission system, hydraulic components, whether or oblique axis inclined disc, closed (pump control) or open (valve) system is very complete variety of hydraulic components, can needs of hydrostatic system components throughout the system complete the project mechanical support. There are parts of the world's largest drive manufacturers, the ZF of Germany, founded in 1915, there are nearly 100 years of history, for all kinds of construction machinery to provide a full range of transmission parts. In electrical fittings, the world's largest electric company Siemens of Germany, and Japan's Toshiba Corporation, Kawasaki, Germany Ph.D. (Bose) companies, has more than 50 years, or even a long history of more than 100 years, to meet the engineering machinery high levels of a variety of electrical systems and electrical components of the request.