Abstract: The current network planning technique is mainly concern with single-layer network, which lacks the efficiency in guiding the production of large-scale manufacturing project. The production process of large-scale project whose activities are tens of thousands is complex, which brings extremely difficulty in describing the corresponding network. However, according to the hierarchical network technology, a complex network can be divided into several simple sub-networks, which means a large type of network can be transformed to a single-layer network, and single-layer network technology can be used to analyze the complex network. In this paper, based on the process of building a large type of network, the issue that how to simplify the network of large-scale project is studied in this paper, several single-layer networks is divided, and the calculation of the float in hierarchical network is carried out. Finally, correctness and feasibility of the conclusion are illuminated through example analysis.

Key words: large-scale projects, hierarchy network, float time