[Chinese dream, great country craftsman] From repairman to great craftsman Li Gang ＂intelligently built＂ China people’s own shield machine.

    International Online Henan Channel Report (Jia Qinqin): The shield machine is known as the "king of construction machinery" and is also known as the domestic "pangolin". From introducing foreign technology to independent research and development and exporting overseas, the domestic shield machine has gradually led the world from scratch. In the wave of tackling difficulties in the localization of shield machines, Li Gang, who is currently the deputy director of the technical management department of the shield company of China Railway Engineering Equipment Group, has grown from a technical school student to the top electrical senior technician of shield machines in China after 20 years of experience in electrical engineering.

Li gang da Guo gong Jiang innovation studio photography jiaqinqin

    As a technical school student majoring in electrical engineering, Li Gang went to work in the overhaul factory of the Tunnel Bureau of the Ministry of Railways in 1992, and learned to repair electrical machinery with his master. "My parents are old railway workers and have been digging tunnels all their lives. At that time, 200 to 300 people could only dig tunnels of tens of meters to 100 meters a month, and the safety factor was low. Some workers even died in the tunnels. Nowadays, with the shield machine independently developed by China, a driver and a dozen auxiliary workers can dig more than 20 meters a day, and it is very safe. " Li Gang said that every time he thinks about the hardships of his fathers when they dug tunnels, he is more devoted to technological innovation.

    According to reports, the earliest tunnel construction mainly used artificial steel hammer drilling and blasting, which is a very primitive method. Up to now, full-face roadheader has been used. However, at the beginning, China’s full-face tunnelling machines were all imported, and "foreign shield" once occupied more than 95% of China’s market.

    Li Gang said that in 1997, the Ministry of Railways spent about 300 million yuan to buy two shield machines from Germany for the construction of the Qinling Tunnel on Xikang Railway. "Even such expensive equipment, because it is not tailored according to the geological conditions of the construction area, often stops working during the construction process. Because of the monopoly of technology, foreign experts and technicians try their best to keep China people away when providing maintenance and technical guidance. At that time, my main job was to carry a toolbox for foreign experts. " Li Gang said with a smile that this also gave him an opportunity to observe the process of assembling and debugging machines by foreign experts.

    "In 2002, we established the first national shield industrialization base in Xinxiang, Henan Province, which is the predecessor of China Railway Equipment." Li Gang said that at the beginning, there were only 18 people involved in the domestic research and development of shield machines, and he was one of them. In order to fully understand the shield equipment, the R&D team carried out construction during the day and disassembled, installed and reassembled the equipment at night, taking the road of introduction, digestion, absorption and re-creation.

    In 2007, the "shield machine simulation experimental platform" passed the acceptance of the national "863" plan expert review group. Later, he devoted himself to the manufacture of the first domestic shield and was responsible for the electrical system of this shield. In 2008, the first shield successfully rolled off the production line and was applied to the construction of Tianjin Metro. It was also the first time that a domestic shield was used in "actual combat" and passed through the famous "Porcelain House" and Zhang Xueliang’s former residence. The mission was successfully completed and won unanimous praise. "At that time, we didn’t dare to say that it was made by ourselves at first. We were afraid that the other party wouldn’t believe it, so we said it was a joint venture. Later, after everyone knew it, they said that they didn’t expect our domestic shield to be so awesome. " Li Gang said proudly when he recalled the first domestic shield machine.

Li Gang is testing line photography Wang Wei.

    As he participated in witnessing the process of localization of shield machine, he deeply understood the importance of independent innovation. "Don’t think that technological innovation is a matter of design, research and development and technical personnel. As front-line workers, we also have a lot of work to do in innovation." Li Gang always educates the employees in his workshop in this way at work, and he also practices it himself.

    In November, 2013, the date of the world’s largest rectangular shield, China Railway No.88, which was used in the tunnel construction of Zhongzhou Avenue in Zhengzhou Metro, was coming off the assembly line. During the debugging process, communication interference was encountered, which made people helpless and seriously affected the production progress. Li Gang led the debugging team of China Railway No.88 in the electrical workshop, and after repeated tests, put forward a scheme to filter out foreign waves by adding winding coils, which solved the communication interference problem well.

Li Gang (right) introduces Wang Wei, a domestic shield machine photographer.

    The liquid level sensor, the core component of shield machine developed and manufactured by Li Gang, has broken the monopoly of foreign enterprises for a hundred years, and its performance ranks first in the world, which has been unanimously recognized by leaders and employees in the field of electrical specialty. In the previous innovative design competitions of China Railway Equipment Group, Li Gang and his team won the third prize twice and the second prize once, and also won the title of "Top Ten Technology Model Equipment", which is rare among front-line workers.

    With excellent technology and innovative spirit, Li Gang has successively won the honorary titles of "2015 Locomotive Medal" and "Henan May 1st Labor Medal" from the All-China Railway Federation. In 2016, the country named the No.436 shield machine after the advanced figure name "Li Gang".

    Chang Xiaolin, Li Gang’s apprentice, said: "Master has not only made many achievements and won many awards, but also has no reservations about technology. He often tells us that we should not only learn the superficial knowledge, but also solve the problem and do the best in every little thing."

    From the beginning of "1", China Railway Equipment opened the door of shield localization. Nowadays, the shields manufactured by China Railway Equipment are not only used in the construction of subways, mountain tunnels and water conservancy projects, but also go abroad and show their talents in international markets such as Singapore, Malaysia, India and Lebanon.