Discussion on the repair of crawler mechanism of t

2022-08-24
  • Detail

As we all know, crawler walking is one of the main walking modes of construction machinery. It is one of the mechanisms that use the most metals and have a high price in construction machinery. At the same time, due to its severe wear and frequent replacement, the repair of crawler walking mechanism has great economic and social benefits, but it must adopt a socialized and professional production mode, At the same time, it is urgent to pay close attention to the development and research of repair equipment and repair technology, so as to meet the needs of this socialized production as soon as possible. Therefore, it is very necessary to discuss and study the repair of crawler walking mechanism of construction machinery

1 has great economic and social benefits

Beijing integrated service department of caterpillar products has a long history in the repair of crawler mechanisms, and has advantages in the repair quantity and repair quality. On the basis of referring to a large number of statistical data and practical experience, they wrote an article that: it takes 6-12 months to purchase new crawler mechanisms, while the repair period is only 1 month, which can greatly improve the utilization rate of machinery; The repair cost is only 20% - 40% of the purchase of new parts, and the service life after repair can reach 80% of the new parts. Therefore, engaging in the repair of crawler mechanism can bring huge economic benefits to users and repair enterprises at the same time

when the wear of the crawler mechanism reaches the service limit, only 3-27mm is removed from the surface of its main part - "three wheels and one belt". At this time, the products shall be delivered properly; In depth epidemic prevention and control related medical equipment production enterprises to carry out measurement and enterprise assistance activities, the wear and tear loss only accounts for less than 10% of the total quality of the "three rounds and one belt". If the method of replacing new parts is adopted, it means that the remaining 90% - 99% of the usable metal will be discarded for the 1% - 10% of the metal lost due to wear, which is really uneconomical; If the repair method is adopted, such as%-99% of the metal can be reused, which is obviously very reasonable, because these metal materials consume countless energy from mining, transportation, smelting, processing to finished products, and produce countless wastes harmful to the environment. The most important thing is that mineral resources are non renewable

at the Ninth National Academic Conference on mechanical maintenance held in September 1999, many experts wrote that the mechanical maintenance mode of the ZI century should be green mechanical remanufacture engineering. At the same time, they pointed out that "the fundamental feature of mechanical maintenance is the reuse of existing equipment. It has the important characteristics of energy saving, material saving, resource saving, especially reducing the primary processing of raw materials, and has the characteristics of natural green engineering". However, the traditional workshop maintenance production mode cannot be compared with it. Only by gradually adjusting the platform center and transforming the machinery maintenance industry according to the flow operation mode of modern machinery manufacturing, can the role of green engineering be brought into full play Due to its large production volume, obvious benefits and mature technology, the restoration of "three rounds and one belt" is particularly suitable for the mode of modern industrial production, and has a successful precedent, which can be promoted as a typical case of our implementation of green machinery remanufacture engineering

it can be seen that the repair of crawler mechanism can not only achieve great economic benefits, but also is a typical technical transformation project to promote green machinery remanufacture engineering and implement the policy of sustainable development. We should strengthen development and research, and actively take measures to promote it in an all-round way

2 it should be organized according to professional production methods

as early as the 1970s, many large construction machinery repair plants carried out the repair of crawler mechanisms, among which the machinery repair plant of the second Engineering Bureau of the Ministry of Railways and the machinery Construction Department of the first Engineering Bureau of the Ministry of railways had relatively perfect equipment, relatively reasonable technology and relatively stable business development. They used electric wrench disassembly, submerged arc surfacing repair, flame surface quenching and other processes, but limited to the planned economy mode at that time, almost all of these repair plants only repaired the crawler mechanism of the construction machinery undertaken by this plant, so there were few repair tasks, and the service life of the repaired parts was not very ideal. Since the 1980s, due to the highly dispersed construction tasks and the insufficient market-oriented development of mechanical maintenance, these large machinery repair plants have shrunk day by day, and the repair industry of crawler mechanism has also gradually disappeared

After the 1980s, some foreign professional construction machinery factories have set up several maintenance centers in Guangzhou, Shanghai, Beijing and other central cities, including track mechanism repair workshops. These repair workshops are equipped with foreign imported and special repair equipment, and adopt advanced and mature repair technology. The repair quality is very good. The service life of the repaired parts is close to 80% of the service life of the new parts, and the price is reasonable. Therefore, the production task is very full. In the repair workshops in Beijing, it is even common to see the "three wheel belt" sent from Xinjiang for repair, which marks the beginning of the prosperity of the repair industry of crawler mechanisms

this decline shows that the track mechanism repair industry is viable, and the difference lies only in the production organization mode. As long as we follow the professional and social model and strive to improve the repair quality, we can turn decline into prosperity. However, these repair workshops alone, regardless of their production capacity and distribution, are far from enough to meet the needs of the repair industry of construction machinery all over the country. Therefore, it is suggested that large machinery repair workshops or construction machinery leasing companies should pay close attention to the establishment of crawler mechanism repair workshops, which will surely create good efficiency for the society and themselves, otherwise it will affect the measurement and operation benefits of equipment

3 pay close attention to the development and research of repair equipment and repair technology

comparative analysis of repair technology and repair equipment of crawler mechanisms at home and abroad shows that they are very similar and have few differences, but the required investment and repair quality are very different. Therefore, it is completely possible and necessary to pay close attention to the development and research of track mechanism repair technology and domestic repair equipment

submerged arc surfacing is used for the repair of "three wheels and one belt" at home and abroad. Domestic "three wheel and one belt" submerged arc surfacing uses general welding wires and fluxes, and mechanical processing and flame surface quenching are also required after welding. Due to the low wear resistance of the surfacing layer and the unstable performance of the quenching layer, the service life of the repair parts is not long; In foreign countries, the "three wheel one belt" submerged arc surfacing adopts special welding wire and flux. Because the weld is well formed, there is no need for machining after welding. At the same time, because the surfacing layer has good wear resistance, it can achieve a long service life without heat treatment. The comparison between the two can clearly see the progressiveness of foreign repair technology. The performance of submerged arc surfacing layer completely depends on the materials of welding wire and flux. Domestic welding experts have made great achievements in the research of submerged arc welding. It is not difficult to introduce the research results of welding experts into the repair process, improve the repair process, and develop special welding wire and flux to achieve a long service life

the repair equipment of "three wheels and one belt" at home and abroad is almost the same, which is made of surfacing machine tools for supporting rollers and supporting rollers, and surfacing machine tools for guiding wheels. It is composed of rail link surfacing machine tool, rail link disassembly and assembly pressure machine tool, rail plate disassembly and assembly machine tool and other special equipment. These foreign equipment are made by WTC. Maru Ma and two professional maintenance equipment factories have made it after years of research and finalization, so the quality, appearance and convenience of the equipment are very good. These domestic equipment are self-developed by the repair technicians of the construction machinery repair factory in the way of technological innovation, so the gap is inevitable. Since these equipment are only relatively simple and low-level products in the machine tool manufacturing industry, it is easy to make up the above gap if they can be jointly developed by the repair technicians of the machine repair factory and the professional technicians of the machine tool manufacturer

according to the preliminary inquiry and estimation, in order to build a "three rounds and one belt" repair workshop, if all the equipment is imported, about US $400000 will be invested; If domestic equipment is selected, it will not exceed 800000 yuan, and the difference between the two is also large, which should be selected according to the specific situation

according to the above discussion, it can be seen that the construction machinery repair plant will take the lead and invite welding experts and machine tool manufacturers to participate in the joint research, joint development and mass production of "three rounds and one belt" repair equipment, and its market prospect is certainly very good

Copyright © 2011 JIN SHI