As a traditional tillage machine in China, large and medium-sized rotary cultivator has played a positive role in improving the level of Agricultural Mechanization in China. Since entering the new century, driven by the policy of benefiting farmers, users have strong demand, products are constantly upgraded, the market is growing steadily, and has maintained a rapid development trend. After the 18th CPC National Congress, the support for "agriculture, rural areas and farmers" will be further strengthened. It is estimated that in 2012, about 350000 large and medium-sized rotary tillers will be sold, continuing to maintain a historical high. Facing the future, large and medium-sized rotary cultivators should achieve their own development, gather development factors, accelerate industrial transformation and meet the upgrading needs of the market and users.

1、 Development history of large and medium-sized rotary cultivators

The development of large and medium-sized rotary cultivators in China began in the late 1950s, completed matching with domestic tractors in the early 1970s and rapidly promoted in the north. It has experienced three stages: single machine development, series development and transformation and upgrading. At the beginning of this century, it has developed rapidly, showing the phased characteristics of steady start, rapid growth, maturity and looking forward to breakthrough. The pace of industrial structure adjustment has been accelerated, and the large and medium-sized rotary cultivators have basically achieved the goals of serialization, diversification and information development.

1. The market is developing steadily. After years of development, China has gradually formed rotary tiller industrial clusters in Jiangsu, Jiangxi and Henan, with hundreds of large and medium-sized rotary tiller manufacturing and supporting enterprises. The industrial manufacturing capacity has begun to take shape, and the production and sales volume has gradually increased. A number of rotary tiller production enterprises such as Henan Haofeng, Yinhua Chunxiang and Xi'an Yaao have emerged, which can manufacture more than 300 types of rotary tillers, It meets the needs of different regional markets. In particular, Henan Haofeng has continued to maintain the momentum of leading the development of the industry in recent years. The market sales of large and medium-sized rotary cultivators increased steadily, and the social ownership exceeded 5 million units. More than 250000 units were sold in 2007, a record high of 350000 units in 2009, and about 35 units are expected to be sold in 2011. It continues to be consolidated at a high level, showing a trend of sustainable development, which is basically consistent with the tractor market. Winter wheat area is the traditional main market for large and medium-sized rotary cultivators, and Northeast China is the main demand area for large-scale composite rotary cultivators.

2. Quality continues to improve. After years of development, the manufacturing level of rotary cultivator in China has been continuously improved, the investment in technology and technology has been continuously increased, the gap with the advanced level has been shortened, and the product quality has been continuously improved. New technologies such as CNC machine tools, complete sets of machining centers, computer automatic welding and flexible machining lines have been applied in the product manufacturing of some enterprises. The degree of product matching has increased and the adaptability has been continuously improved. The application level of materials has been continuously improved. From the products in the current market, materials with corrosion resistance, wear resistance, antifriction, impact resistance and fatigue resistance have been widely used in products. The gear materials of large and medium-sized rotary cultivators in China are mostly 20CrMnTi and other low-carbon alloy steel, which has greatly improved the product quality compared with the previous products; The cutter shaft is made of low-carbon steel pipe, the box body is made of ball milled cast iron, the rotary tillage cutter is made of manganese steel or rare earth steel, engineering materials and composite materials have been applied in product manufacturing, which has promoted the continuous improvement of the overall quality of large and medium-sized rotary cultivators.

3. Product development is diversified. With the acceleration of the adjustment of modern planting methods, farming agronomy and agricultural structure, China's rotary cultivator industry has realized the development of multi lineage and serialization, initially formed dry land, paddy field, single and composite rotary cultivator products, and basically realized the coverage of large and medium-sized tractor products. In terms of product characteristics, large and medium-sized rotary cultivators and tractors mainly adopt three-point suspension mode. Rotary cultivators are divided into two modes: intermediate transmission and side transmission; The frame structure is mainly composed of auxiliary beam structure and frame structure, and the cutter shaft is divided into integral structure and split structure. Due to different working conditions, dry field and paddy field products differ greatly in product structure, cutter shaft bearing and so on. The product has developed from single function to multi-purpose and composite function. Based on rotary cultivator, regional products with different combination functions such as stubble removal, rotary tillage, subsoiling, sowing, ridging and suppression have developed rapidly according to different agronomy.