Reporter 2 from was informed that the enterprise independently developed multi-specification roadheader main bearing has passed the working condition simulation test verification, entered the batch engineering application stage.
Roadheader is a high-end equipment in the field of tunnel engineering and construction, bear the rock drilling and road opening, across the river and across the sea construction of the country’s major infrastructure projects of the heavy responsibility.
The main bearing, as its core key components, works in underground tunnels for a long time, and its reliability and safety requirements are extremely high. Once a failure occurs, it is difficult to dismantle and replace, which will lead to construction paralysis and cause huge losses. Previously, due to the lack of test and application data to support the domestic main bearing, it is difficult to effectively verify the reliability of the product, engineering applications to promote the difficulties.
In order to break through the three major dilemmas faced by the domestically produced main bearings, which are “can’t be used, don’t dare to be used, and won’t be used”, Tiejian Heavy Industry gives full play to its advantages of knowing both the design of roadheader and the working conditions of the main bearings, combines with the experience of construction application, collects the data of the load of complex working conditions, and matches the characteristics of the working conditions to carry out targeted R&D and research and breaks through the high-performance materials, high-reliability design, high-precision manufacturing, and high-reliability manufacture of the main bearing. It has broken through the key core technologies of the whole life cycle, such as high-performance materials, high-reliability design, high-precision manufacturing, and high-reliability test, and replicated the simulation test of the main bearing in soft soil, hard rock, and uneven soft and hard geological conditions, which systematically verified the long-life service capability of the independently-developed main bearing to adapt to the complex and harsh working conditions, and has laid a solid foundation for the development of the batch engineering application and industrialisation of the domestically-made main bearings.
The breakthrough of this core component is inseparable from Tiejian Heavy Industry’s investment in science and technology research and development. According to reports, only in the first quarter of this year, Tiejian Heavy Industry R & D investment totalled 233 million yuan, R & D investment accounted for the proportion of operating income of 9.84%.
In promoting the application of domestically produced main bearings, Tiejian Heavy Industry overcame heavy resistance, spoke with technical strength and test data, and steadily pushed forward the application of domestically produced main bearings in phases and batches, and dug more than 20 kilometres in typical representative projects, and the application locations ranged from coastal cities to central and western regions, including Beijing, Shanghai, Shenzhen, Hunan, Jiangsu, Inner Mongolia and other provinces and cities; the application scenarios covered vertical wells exploration, oil pipelines, urban metro, pumping and pumping. The application scenarios cover vertical well exploration, oil pipelines, urban metro, pumped storage and other key projects; the application geology covers unstable soft rock strata, compound strata with uneven hardness and softness and high pressure fluctuation, as well as hard rock strata with full section.
Especially in the Pearl River Delta region, known as the “geological museum”, overcame the multiple tests of 130MPa extremely hard granite, multiple sections of large depth on the soft and hard strata, as well as long tunnels, high-pressure and frequently changing strata and other harsh geological conditions, and successfully achieved the goal of the tunnel project section through, and fully verified the reliability and stability of the main bearings made in China. The reliability and stability of the domestic main bearing is fully verified.
The person in charge of TCCI said that the series independent development and batch application of domestic main bearings breaks the inherent notion of “domestic main bearings” that has long been talked about in China, and provides a strong guarantee for promoting the safe and high-quality development of the tunnel boring machine industry.