China's milling machine production started late in the early 1980s began to develop, the main structure of two forms: First, in the agricultural wheeled tractor mounted on the milling device and constitute a simple cold milling machine, its simple structure , For moderate strength below the asphalt pavement milling; Second, self-type cold milling machine, the past two years have a certain development, the main models of the use of performance has been fully able to meet the domestic high-grade highway and municipal road maintenance requirements , A good performance and cost compared with foreign imports of products also have a greater competitive advantage, but in the variety specifications, technical level and accessories, etc. there is still a big gap.
At present, the domestic models more reference to the European milling machine technology and experience in the power, hydraulic and control systems are used on the international support, it can be said in the system configuration reached the international advanced level. From the perspective of intellectual property rights, some domestic products such as Shanghai DOAN Machinery Co., Ltd. produced DA2000 and Xi'an Hongda Transportation Technology Co., Ltd. produced DA1900 and DA1200, not only has a complete intellectual property rights, but also in the machine system, control system and software The design and manufacturing processes and other aspects have reached the international advanced level.
In the future market competition, China's milling machine manufacturers should play the following advantages: ① the use of China has joined the WTO favorable conditions, establish an international design ideas, strengthen international technical cooperation, technical and international development Level of synchronization, and strive for greater high-end products market; ② to play the advantages of localization, to provide users with timely machine technology to the supply of accessories, such as all-round services; ③ the use of low labor prices, lower machine costs, Play a price advantage, for more low-end users, to expand the market; ④ attention to research and development in line with China's road characteristics of proprietary technology and product line for the road maintenance project services to promote China's road transport technology progress. Foreign road milling machine development and engineering applications have a long history, has accumulated rich experience, formed to DOAN products as the representative of the European style and the United States RoadTech company, CMI company, Caterpillar products as the representative Of the North American style. They work the same principle and process, the engine installed capacity is basically the same, the difference is that the European milling machine using four-track walking mode, compact structure, compact, more use of electronic control technology, especially the current digital electronic network control Technology; and North America's milling machine are used three crawler walking mode, rough shape, more solid. Table 2 lists the major technical parameters of several typical foreign products.
Foreign road milling machine technology has reached a high level of technology, summed up the following characteristics.
1, advanced and reasonable chassis structure Milling machine chassis mainly to the whole frame and four-wheel walking structure, drive and steering methods are mainly hydrostatic transmission.
2, give full play to the best milling power Milling machine on the automatic hydraulic power regulator can be based on road surface hardness and milling depth to control the milling rotor feed speed, you can automatically adjust the milling rotor speed and milling machine walking speed, The milling machine is always in the maximum power utilization state, and does not occur overload work.
3, the engine power increases the same milling width of the new milling machine power is growing, the production efficiency.
4, the larger the depth of milling The new milling machine a milling depth of more than 300mm, so that the entire carriageway full thickness of the pavement possible.
5, the performance of good milling rotor Most of the cold milling machine will be fixed on a few pieces of semi-circular tiles on the tiles, the number of tiles installed on the rotor to adjust the milling machine milling width.
6, simple milling load milling machine rear loading conveyor conveyor to complete the rapid receipt, and milling objects into the car. Through the hydraulic mechanism to adjust the discharge height, and the conveyor belt can swing about 40 ° ~ 50 °, in order to achieve roadside loading.
7, a large number of advanced technologies such as all-wheel drive technology and mechanical and electrical integration of integrated control technology, intelligent fault diagnosis and maintenance system, accurate automatic leveling system, safety self-protection system and automatic power distribution system.
8, large capacity container tank, diesel tank volume larger, the machine work fuel, cooling water filling interval is long, short standby time.
9, the modular design of the engine and its peripheral components - hydraulic pumps, hydraulic valves and cooling systems are installed in the same chassis, all the solenoid valve are assembled in the same distribution valve, easy to adjust, testing and maintenance.