Development of small hydraulic excavator with the

Comprehensive analysis of the development of small hydraulic excavators

Guide: as earth rock construction machinery, hydraulic excavators play an increasingly important role in various engineering construction fields, especially in infrastructure construction. They are fully utilized in airports, oil fields, mineral reserves, urban and rural construction, agricultural water conservancy and other fields, and are the largest and increasing middle-class sales in the construction machinery industry

as earth rock construction machinery, hydraulic excavator plays an increasingly important role in various engineering construction fields, especially in infrastructure construction. It is fully utilized in airports, oil fields, mineral deposits, urban and rural construction, irrigation and water conservancy and other fields. It is one of the products with the largest sales volume and the highest growth rate in the engineering machinery industry. Among them, the production and sales of small hydraulic excavators (hereinafter referred to as small excavators) have also increased rapidly in the past two years, which has attracted the positive attention of many construction machinery manufacturers in the hardness value of cloth hardness across the country. At present, there are many projects in the production of small excavators or preparations. The following is a simple analysis of the development of small excavation combined with its characteristics. 1、 In the small excavation market, domestic small excavators mostly refer to products below 10 tons. Because they have many functions of medium-sized excavation machinery, and have the advantages of transportation, energy consumption, flexibility, adaptability, low price, light weight, convenient maintenance, they are widely used in small-scale construction and production fields such as hydropower, transportation, municipal administration, gardens, farmland reconstruction, oil pipelines, etc. From the current sales situation in China, more than 90% of the market share is occupied by 16 ~ 32 ton medium-sized excavators. In 2003, 20 ~ 23 ton excavators accounted for 86% of the excavator market share. Compared with medium-sized excavators, the domestic market for small excavators started late, and excavators below 15 tons account for about 5% of the total domestic market every year, which is still in its infancy. However, driven by the unprecedented prosperity of the whole market, there is a clear demand for small excavation in economically developed areas, from more than 300 in 2000 to more than 1500 in 2002 (in 2002, the sales volume of China's small construction machinery was only 2786), and more than 3000 in 2003. Although with the economic development, the refinement of division of labor, the active attention of local manufacturers and the massive involvement of foreign brands, China's small excavation market will be rapidly expanded, and the market competition pattern will also change dramatically. However, there is an indisputable fact that China's small excavation market has been started. The large-scale construction in Japan, the United States, Europe and other developed countries and regions has passed, the infrastructure construction has been relatively perfect, and has entered the period of maintenance, repair and renewal. The market of small and medium-sized and multi-functional construction machinery products is quite good, accounting for 50% - 70% of the total sales of heavy construction machinery, and the sales volume is large. In terms of small excavators alone, from 1999 to 2002, the annual demand for small excavators in Japan, North America and Western Europe reached 70000 to 80000 units, of which 19272 units were sold in Japan in the first half of 2003, accounting for more than 46% of the total domestic excavator market in Japan. The proportion share of Europe and the United States is greater than this example. Looking at these small hydraulic excavation machines, their models and machine weights are developing in the direction of miniaturization (models less than 6 tons), and the concept of rear tailless rotation is becoming more and more popular, which is widely used in farmland construction, management, manor construction, material handling, pipeline laying, etc. 2、 Domestic and foreign manufacturers and product characteristics 1. Main domestic manufacturers and product characteristics: many construction machinery manufacturers across the country are actively involved in small excavation projects. Domestic manufacturers and sellers of small mining machinery mainly include Guangxi Yuchai, Hunan Shanhe intelligent, Jiangxi Nante and other manufacturers. As the largest production base and export base of small construction machinery in China, Guangxi Yuchai mainly produces small excavation products of YCl3, yc25, yc35, yc65, yc85 and other models. Recently, it produces more than 1000 small excavation products of different models every year. The products adopt Yuchai engine, some of which are equipped with Cummins engine, and the main hydraulic parts use imported components such as Nachi from Japan. YC type adopts international configuration of key components, Toshiba load sensing system, pilot control, computer monitoring, and excellent performance. The factory has a complete range of small excavation products, mature technology, and many self-made parts, so that its products have a price advantage. Hunan Shanhe intelligent set up a project to develop a small hydraulic excavator in July 2001. In October of the same year, it completed the prototype and participated in the 6th BICES (Beijing International Construction Machinery Exhibition), which was highly praised. In recent years, it has produced series products such as swe45 and swe80. The products use engines such as Changchai and Perkins, main hydraulic components such as Kawasaki, variable flow total power control system and pilot control. Relying on the technology and talent advantages of Central South University, it plans to build a research institute and a new 157000 M2 Shanhe intelligent industrial park to ensure product quality and large-scale production capacity. The shape and appearance quality of the small excavation products of the factory are good, and the components have formed an international configuration, which has gradually grown into a bright spot in China's small excavation market. Jiangxi Nante has been engaged in the manufacturing and sales of four wheels and vulnerable parts of excavators. In 2001, it began to try to produce small hydraulic excavator (nt60) and achieved good sales results. At present, the developed products include nt15, NT45, nt60, nt80, nt130, NT200 and other models. At present, due to the limitation of production and service capacity, it mainly produces NT45 and nt80 small excavation models. In 2003, more than 100 sets of two products were sold. The hydraulic system of the product is similar to that of Yuchai. The main hydraulic components are components such as Kawasaki or Nachi from Japan, load sensing system and pilot control, but the engine configuration adopts domestic products such as Changchai and shangtuo. Because it has been engaged in the manufacture of excavator accessories and domestic matching of components, it has great flexibility in sales price, but there is still a certain gap between product quality and Yuchai and Shanhe intelligence. In recent years, Korean Hyundai and Daewoo have made and sold r60-5, dh55 and other models in China. Kubota of Japan also wholly-owned production of small excavators in Shanghai. Hitachi, Kobe Steel, Ishikawa island (IHI), Kaikai have achieved 42billion yuan of industrial added value, and world-famous excavator manufacturers such as Ingersoll Rand and JCB are actively promoting their series of small construction machinery to China. 2. Major foreign manufacturers and product features: Volvo, Terex, Kobelco, IHI, Yanma R and other world-famous excavator manufacturers have a wide range of small excavators. It can be said that almost all excavator manufacturers are involved in small excavators. Daewoo produces dh55, dho35, dho3op, dho15p, dho10 and other series of small hydraulic excavators. Except that the boom of dh55-v type has two options: rotatable and non rotatable, the boom of other dho3 5, dho30p, dho15p and dh010 are all rotatable. JCB product series covers all the functions that small excavator products can provide, and forms a product structure with high-low matching. Equipped with JCB diesel engine and walking and slewing motor, it has two mining operation modes that meet ISO standards and SAE standards for selection, LCD displays all kinds of data, and has good function integration. It can easily plug and unplug hydraulic quick connectors of various tools. Case's CX series excavator is the first excavator to be introduced to the Chinese market with the most advanced "tailless rotation" characteristics of excavators in the world. Case's CX series tailless Rotary has two models, Cx35 and Cx45. The boom can swing back to the left and right, ensuring normal excavation when leaning against the wall, and improving the working vision. The two speed driving system, with the unique buffer groove design of the control valve rod, can prevent the sudden speed change of the machine from causing vibration or impact to the system. Hitachi produces EX Series rear ultra small rotary micro excavator. Zaxls55ur, launched in 2003, has been tested in Japan for many years and has been improved accordingly for the Chinese market, so that its construction scope can be further expanded and the construction period can be shortened. The new HHH hydraulic system can provide the best flow to all actuators regardless of high or low load, so as to ensure the stability of composite action and reduce operator fatigue. The load sensing hydraulic system equipped with Volvo small excavator represents the most advanced technology today. This system can combine all the control systems together, and belongs to the standard configuration of Volvo small excavator series. Even if other actions are carried out, the machine can still maintain linear motion. The quick connect system is optional. 3. The main technical parameters of some models (5 ~ 6 tons): III. suggestions for developing small excavators. 1. XCMG has a certain degree of technical advantages over other new product development in terms of technology, manufacturing and quality assurance of excavators. Products such as 20, 21 and 22 ton Crawler excavators that have been produced in batch, WYL20B and ew20 tire excavators that have been trial produced, WZ S300 tunnel excavators and loaders that have been developed, and WZ excavators and loaders have provided some experience in the development of small excavators in various aspects such as technology and manufacturing, and are of great help to the correctness, inheritance and realization possibility of the overall scheme of the products. Therefore, as a member of the excavator series, the development of small excavation has no major problems in technology, manufacturing, quality and so on. 2. Referring to foreign brands of small excavators, the developed products should have the following main characteristics: low engine noise and emissions, high environmental protection requirements, to adapt to urban residential buildings· Flexible operation, small turning radius, even zero turning at the tail, suitable for narrow occasions· The operation is convenient and safe, and electronic control and monitoring technology are applied to improve the comfort of operation· In order to adapt to urban working conditions, rubber or toothless track shoes are preferred to protect the road surface· 360 ° rotation, (even the boom can rotate within a certain range) to increase the adaptability of operation· Quick change device, quick change of various working accessories· With bulldozer function· Convenient maintenance: 3. The key to the successful development of small excavation · product positioning: This is the basis for the successful development of new products. Products below 10 ton level are classified in more detail, including 10, 8, 6.0, 5, 4, 3.2, 1.3 ton level products. Which type is suitable for which user groups? Which category sells the most? The largest market potential? These require in-depth research. Only with accurate market positioning can we seize market opportunities, grasp the mainstream of the market and win market share. It is understood that at present, Beijing Hyundai produces two types of 6-ton (R60) wheeled and crawler models; Daewoo Yantai increased investment, established a base specializing in the production of small excavators, and introduced new 5.5-ton improved models and 7.5-ton new models. Its 5.5-ton model maintained a monthly production of more than 100 units for several consecutive months; Chengdu Shengang sells 5, 1.5 ton small excavation; Hefei Hitachi and Komatsu Shantui also sell small excavations below 6 tons. According to the statistics of relevant sales data, during the period, 5.5 (6), 3.5 and 1.3 ton small excavation products dominated, of which 5.5 (6) ton small excavation increased the most, and the sales volume in 2002 accounted for nearly half of China's small excavation market; In addition, jiangxinan special class first tried production with type 60 (6 ton class); Therefore, referring to the above information, it is suggested to develop products with 5.5 and 6 ton small excavation as the leading· Cost control: the small excavator system is complex, and cost control is difficult. The purchasing power of user groups must be considered in product development. High cost performance is the main competitiveness of long-term product development, so cost control is an important means to determine product profits and competitiveness. It is particularly important for the actual situation that the purchasing power of domestic user groups is still insufficient. The user group that the product is suitable for determines the high-end and low-end configuration of the product. The small excavation is mainly composed of working device, cab, slewing mechanism, turntable, power device, crawler chassis, machine shed, counterweight