China started the boom arm pump concrete pump started in the early 1980s, the initial is basically the introduction of spare parts assembly, or through the introduction of technology and trade combined with the introduction of technology and part of the introduction of part of the production model. In the 1950s, China produced a mechanical concrete pump, due to the low level of technology at that time, production volume is very small, in the early 1980s, the total amount of domestic concrete pump truck is still less than 200 units, armored concrete pump The car is a blank. During this period, some large-scale concrete pouring projects in our country basically relied on imported equipment to a large extent. Since the early 1980s, after more than 20 years of hard work, our country boom-type concrete pump truck has made considerable progress, design level, manufacturing capacity has been greatly improved. According to statistics, at present, China's concrete pump manufacturer has reached more than 100, located in all parts of the country. However, due to the technical level of various manufacturers, production processes, production capacity, such as uneven, the product gap is also larger. At present, the strongest production capacity in China is the first tier represented by Sany Heavy Industry, Zoomlion, Xuzhou Heavy Industries and Futian Heavy Machinery. The second tier consists of Liaoning Hainuo, Hubei Construction Machinery, Anhui Xingma and Shanghai Hong Deli and other enterprises, their production accounted for more than 90% of the industry. In recent years, China's boom-type concrete pump truck has developed rapidly. Although the product stability and technology are not as good as foreign products, it has made great strides over the products of the 20th century. In terms of cost performance, after-sales service and other aspects of our products have obvious competitive advantages, and more in line with the actual construction of the domestic situation. Among them, Zoomlion, Sany Heavy Industry in the arm-type concrete pump truck research and development walk in front of peers. Zoomlion formulated the "concrete pump truck" standard, but also developed a remote maintenance and positioning system for pump trucks. Sany Heavy Industry concrete pump truck, whether in the pumping pressure, pumping displacement, or in terms of stability, reliability, etc., with well-known foreign brands comparable to the pump machinery products have been sold to the Middle East , North Africa and South Asia and other places. As can be seen from the 123 patents issued by the State Patent Bureau, the patents obtained by the domestic pumping machinery mainly include the pumps, pump gates and pump control, hydraulic and electrical appliances, etc. This shows that the domestic enterprises' Research more attention, this is also the field of domestic pumping machinery is relatively weak. Followed by the pump spare parts and jib, the number of patents in the past 20 years, only more than 100, which also contains foreign companies to apply for a patent, which shows that China's armor-type pump business R & D investment is not enough. However, our country has strong technical research and development capabilities of companies such as Sany Heavy Industry and Zoomlion are increasing research and development, and achieved gratifying results. First, the boom-type concrete pump truck major components of each dominate Domestic boom-type concrete pump truck as a late start in the past two years all domestic enterprises have stepped up the introduction of technology and quality control, design and development of the arm with independent intellectual property rights Rack-mounted concrete pump truck, technical innovation to become booster concrete pump truck development booster. The major components of the technological development trend also represents the development of the domestic boom truck concrete pump truck development. Second, the chassis presents a variety of chassis engine for boom-type concrete pump truck to provide work and driving power. Therefore, the performance of the chassis engine directly affects the performance of boom-type concrete pump truck. Currently domestic boom-type concrete pump truck commonly used Volvo, Mercedes-Benz, Isuzu chassis, 2005 has made use of domestic chassis boom concrete pump truck to the market. With the increasingly mature domestic boom truck pump market, vehicle profit margins continue to decline, in order to meet the different needs of users, using domestic chassis and imported chassis boom concrete pump truck will own a place in the market . Domestic boom-type concrete pump chassis almost all imported chassis. One Isuzu chassis technology is mature, perfect service in the country, the price is relatively cheap; Volvo and Mercedes-Benz chassis luxury appearance, driving comfort, high degree of automation, the use of diesel EFI technology, low fuel consumption. At present, the engine used in the domestic boom-type concrete pump truck chassis meets the Euro â…¡ or above standards, to meet the environmental requirements of large and medium-sized cities. Third, the structural components more applicability Boom concrete pump truck operation is often limited by the upper space, requiring the top of the boom when the boom is the lowest, 4-fold below the boom generally use a single R or Z-type folding. More than 5 knuckles of jib due to space constraints, the general use of folding type RZ to achieve the boom to expand, Shoulong, applicability, mobility and flexibility to enhance, especially in the tunnel and indoor work construction, the efficiency is significantly improved. The length of the first domestic boom to 37m majority, the past two years have become increasingly longer trend, the next few years, with the increasing demand, there will be a longer boom concrete pump truck to the market. Boom concrete pump truck leg operations are often subject to space constraints, especially large jib concrete pump truck. Therefore, all manufacturers have to combine their own experience to find solutions. Therefore, the arm-type concrete pump truck leg design presents a personalized, diverse features. Currently on the market with dual swing and X-shaped legs mostly. Longer fabric boom and more flexible outrigger structure are the major trends in the development of boom-type concrete pump trucks. Various types of folding are used in combination to make the boom design more flexible and lighter. The form of legs is also more and more flexible, the extensive use of unilateral legs, so that the boom concrete pump truck to adapt to different site conditions. Fourth, the center pumping system pressure is higher, the larger the pressure transmission pressure, the greater the amount of transmission will become the future boom pump pump center boom system development trend. In the initial stage of the design of domestic boom-type concrete pump truck, the diameter of concrete transportation is about 200mm, the output displacement mostly concentrates below 100m3 / h. Since 2004, the concrete delivery cylinder with the diameter of 200mm has exited the pump truck product, Pump products have applications. At present, the market is the most common transport bore 230mm, travel in 2100mm, or even longer, the output displacement of 120m3 / h or more. With the booms of boom-type concrete pump truck getting higher and higher, the models become bigger and bigger, and the cylinder diameter of the delivery cylinder is also getting larger and larger. The cylinder with the largest diameter in China has reached 260mm and the displacement of concrete is greater. However, From the overall configuration of the machine, due to the height of the machine and the width of the frame, the larger cylinder diameter concrete conveying cylinder is greatly restricted in the application of the arm type concrete pump truck. At the same time, the larger the cylinder diameter of the concrete delivery cylinder, the greater the output displacement, the greater the required chassis engine power will be, and the greater the vibration displacement of the boom will be when the whole machine is working in large displacement. Therefore, large-diameter arm-type concrete pump truck if you want to replace the common bore diameter of 230mm, but also do a lot of work, go a long way. Due to the progress of the project requirements are getting higher and higher, now require pumping displacement of 80 ~ 120m3 / h more and more projects, large displacement will become the future development direction of boom-type concrete pump truck. In addition, pumping pressure is getting higher and higher. Before 1971, most of the concrete outlet pressure does not exceed 2.94MPa, later increased to 5.88 ~ 8.38MPa, has now reached 22MPa, but also continue to increase the trend. Fifth, the hydraulic system to the integrated direction of the development of hydraulic system is the core of boom-type concrete pump truck, hydraulic system quality will directly affect the host performance and efficiency. Domestic arm-type concrete pump truck hydraulic system mostly imported technology design, there are 2 kinds of control circuit, a closed-loop hydraulic system to Xuzhou Heavy represented, the other is open hydraulic system circuit to Sany Heavy Industry to represent. Open circuit and closed circuit have their own advantages and disadvantages, closed circuit commutation impact is small, small heat, simple structure; and open circuit is the most prominent feature is able to easily control the pump displacement according to the load, in particular When pumping over short distances, the pumping capacity is large enough to take full advantage of the engine power. After years of experimental verification, these two kinds of hydraulic circuits have been relatively mature in the application of boom-type concrete pump truck, but have their own characteristics in achieving various functions, technically there is no problem of who is superior and who is inferior, Only in the selection of hydraulic components there are some differences. Boom concrete pump truck commonly used open system and constant power control, especially the large flow pump, open system with low oil temperature, high reliability, easy maintenance and many other advantages. At the same time, the whole hydraulic control technology, computer control technology has made a breakthrough. Such as Sany Heavy Industry Products hydraulic steering and computer closed-loop control technology has been widely used. Sixth, the control system function More electrical control is the key to determine the efficiency of the pump truck. Boom concrete pump truck electrical system developed rapidly in the past two years, all domestic manufacturers have been from the initial relay control for the PLC control, greatly improving the reliability of the product. Boom concrete pump truck electric control system from the traditional PLC control to the dedicated controller and computer intelligent control of the development, through the touch screen, you can achieve man-machine dialogue, a variety of operating parameters can be stored and displayed to achieve the vehicle's auto monitor. Once the machine running failure, in addition to alarm tips can also be transferred to the relevant parameters for fault analysis, diagnosis. The application of boom intelligent control system technology can realize the luffing of boom with the same level and intelligent pouring. VII. Technological innovation has become the focus of the new round of competition With the intensification of market competition, the development trend of domestic boom-type concrete pump trucks has a direct impact on the development of domestic manufacturers. How to grasp this trend has become the domestic boom-type concrete pump The focus of car manufacturers Domestic boom-arm concrete pump truck developed rapidly in our country, more and more features, performance, superior and reliable. PLC control, automatic electric displacement control, automatic load feedback control, high and low pressure automatic switching has gradually become the standard armor concrete pump truck manufacturers. At the same time, the development of pumps with mixing drums, jetting machines and other auxiliary devices such as cloth truck will be the development direction of domestic boom concrete pump truck. Boom concrete pump truck in our country so far, the product has matured, the system will not be a big problem. After the hot competition will be reflected in the improvement of function and reliability, reflected in some design details, some seemingly insignificant issues, will be able to further develop in the market, or even the decisive factor for survival. The use of ergonomic design, focus on operational performance, improve the working environment for the operator to improve comfort, reduce noise and vibration, embody the people-oriented features to increase the appearance of design, which will be our future for quite a long time Research topic At the same time pay more attention to environmental protection, health, real body