1.2.1 Research and Development Abroad
The role of the undercarriage is to support and install the engine and its components to form the overall shape of the vehicle, and to transmit power to make the vehicle move and ensure normal driving.
In foreign countries, the development of crawler-type walking undercarriage was earlier. As early as 1986, W.C.Evans and D.S.Gove completed a research on the traction performance of a rubber track and a four-wheel drive tractor on hard ground and cultivated land. Under the same undercarriage structure, the traction efficiency of rubber crawler is higher than that of dynamic traction. The maximum traction efficiency is 85% to 90% on cultivated land and hard ground, and 70% to 85% for four-wheel drive tractors. Since then, there have been many researches on the performance tests of rubber track tractors and four-wheel drive tractors, such as the performance tests of rubber track tractors and four-wheel drive tractors on four types of ground (unploughed, raked, plowed oat stubble and corn stubble). The relationship between traction performance (dynamic traction ratio, traction coefficient and slip rate), etc.
In terms of market development, crawler tractors produced abroad have strong competitiveness in terms of technical level and production capacity. The international competitor of crawler tractors is Caterpillar’s line of rubber crawler tractors. YTO’s products are not competitive in terms of technical level or production capacity, only the price is attractive, but from the analysis of the performance-price ratio, YTO’s products are still at a disadvantage. Therefore, the company’s new generation of high-power rubber crawler tractors will be put on the market as soon as possible, so as to consolidate the traditional market and give play to the competitive advantage.
1.2.2 Domestic research and development
my country has a short history of producing crawler undercarriage, which is basically the same as the development of cranes. Compared with the advanced countries in the world, the domestic crawler undercarriage has a low technical content and a low degree of serialization, and there is still a certain gap in manufacturing and design. In recent years, the rapid development of domestic crawler cranes has brought opportunities for the development of crawler undercarriage, and the series has been continuously improved.
For more than 20 years, some domestic universities, research institutes and enterprises have done certain research on rubber tracked vehicles, such as: China Agricultural Mechanization Research Institute and Nanjing Agricultural Mechanization Research Institute on the rubber track of rice harvester, Qingdao Institute of Architecture and Engineering The experimental research on the ground pressure of the grounding teeth of the rubber track, the research on the rubber track tractor by China YTO Group Co., Ltd. and the research on the rubber track by the Hangzhou Yonggu Rubber Factory, etc. The following mainly introduces the research on rubber track tractors. In 1994, China YTO Group Co., Ltd. carried out a comparative test using metal crawler and rubber crawler on a crawler tractor with a traction rating of 3 t, and the test was carried out on hard loess ground. At the same time, the relevant undercarriage has also developed to a certain extent. Since then, YTO has also carried out use tests on tractors and bulldozers using rubber tracks. It is mainly the wear resistance test of the rubber track, the derailment test of the rubber track, the life test of the rubber track, the reliability test of the rubber track with different structures, the elongation test of the rubber track and the general work verification.
Crawler tractors and deformed products in the domestic market are still dominated by YTO products. The sales of such products are in a state of fluctuation due to the influence of national macroeconomic policies. Whether as a variant of construction machinery, traction or drive power for farm work, or as a walking undercarriage for agricultural machinery, its functions are not completely replaceable by wheeled tractors. However, affected by national policies and the development of high-power wheeled tractors, it will be in a passive situation in the market competition in the long run. In a word, the development direction of the undercarriage corresponding to the crawler, as the running mechanism of the related machinery, has always revolved around the development of safety and reliability, operational comfort, environmental protection and energy saving. In this regard, domestic and foreign efforts have been constantly improving.
Post time: May-29-2022
