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Development of space grid structure in our country, especially the bolt ball node network frame originated in xuzhou city, jiangsu province, in the late 1980 s and 90 s, xuzhou rack industry thriving, almost scored the most domestic project, and enter the international market, for our country become the world's superpower rack wrote a glorious page.

Xuzhou: bolt ball node grid township. What is bolted ball joint grid? At present, in the toll station, gas station, sports hall, convention and exhibition center, airport terminal, railway station elevated waiting room and platform can be found everywhere. The appearance of bolted ball nodal grid structure in China reflects the wisdom of Chinese people.

At the end of 1960s, in another international exhibition, the exhibition shed built by a foreign enterprise with bolted ball joint net frame aroused many people's interest. Although Chinese engineers have consulted them in various ways, they have refused to answer.

In the late 1970s, engineers in the third room of the steel structure of the standard design institute of the Chinese academy of building sciences, after studying and designing the bolted ball joint net frame and hollow welded ball joint net frame typesetting diagram, nearly 80 kinds of various specifications and sizes and 3 kinds of load level net frame diagram, are available for users to choose.

Xuzhou city network frame manufacturers like mushrooming emerged, according to statistics, there were more than 200 licensed network frame production enterprises, the network frame, steel structure enterprises and accessories production and other employees nearly 30,000 people. At that time, xuzhou, the construction of the network is booming, is the well-deserved home of the network.

With the further increase of steel output in China, the country has put forward the policy of actively adopting steel structure in construction, and popularizing steel structure as a new construction technology, the steel structure industry in China has been developing rapidly. In particular, the state general administration of quality and technology supervision, inspection and quarantine approved in xuzhou city to build the state grid and steel structure product quality supervision and inspection center, the glory of xuzhou grid home is not far away.

Xuzhou network frame in the domestic and international are renowned, in addition to the town of the network frame reputation, xuzhou or the national network frame parts production base, therefore, under the support of the government, xuzhou's network frame, steel structure enterprises will have great success.