Li Dongbo

Research on Multidisciplinary Optimization Design of Bridge Crane

Bridge crane is one of the most widely used cranes in our country, which is indispensable equipment for material conveying in the modern production. In this paper, the framework of multidisciplinary optimization for bridge crane is proposed. The presented research on crane multidisciplinary design technology for energy saving includes three levels, respectively: metal structures level, transmission design level, and electrical system design level. The shape optimal mathematical model of the crane is established for shape optimization design of metal structure level as well as size optimal mathematical model and topology optimal mathematical model of crane for topology optimization design of metal structure level is established. Finally, system-level multidisciplinary energy-saving optimization design of bridge crane is further carried out with energy-saving transmission design results feedback to energy-saving optimization design of metal structure. The optimization results show that structural optimization design can reduce total mass of crane greatly by using the finite element analysis and multidisciplinary optimization technology premised on the design requirements of cranes such as stiffness and strength; thus, energy-saving design can be achieved.

Research on Charging Combination Based on Batch Weight Fit Rule for Energy Saving in Forging

As a traditional high energy-consuming industry, the forging industry consumes a lot of energy. The activity consuming the highest energy during forging process is the heating. The problem regarding how to separate workpieces with the same holding temperature and holding time and combine them for charging in forging was analyzed and a model based on batch weight fit rule for optimizing the charging combination with the goal of energy saving was proposed. A genetic algorithm was adopted to optimize and solve the model in order to reduce energy consumption in forging. In addition, an instance was given to prove the effectiveness of the proposed model.

Camber deformation estimation of bridge crane and energy-consumption analysis

The crane is a mechanical device used to move materials in modern production. It plays a very important role in the national economy by greatly reducing labor intensity, improving production efficiency, and promoting social development as an indispensable auxiliary tool. The energy consumption of a crane is very large. There are several factors influencing energy loss, especially the camber of the girder, which is thought to compensate for the operation downwarping and, thus, decrease the energy consumption of trolleys with improved operation performance. Thus, analysis and calculation of the camber for crane girder is necessary in order to design a reasonable camber curve for the compensation of girder deformation by self-weight and loading. In this study, the deformation source is analyzed, and an estimation model of camber for the bridge crane is proposed. The camber is theoretically discussed and estimated with respect to self-weight, wheel pressure, and welding. As a result, the optimal corresponding camber curve that could compensate the deformations by self-weight, wheel pressure, and welding were obtained. Calculation of the energy consumption of the trolley is also presented. By using a 50-t, 31.5-m double girder crane as the research object, calculation of its camber and design of the reasonable camber curve for energy-saving were analyzed and demonstrated. These results may provide a design reference for girder camber curve and validation of the effectiveness of crane simulation modeling.

Research of Forging Job-Shop Scheduling System Based on Quality of Service

Compared with the traditional discrete manufacturing, forging enterprise’s order-driven, integrated procedure, various product and multi-process, medium and small manufacturing mode result in the complexity of job-shop scheduling. To solve this complex scheduling problem effectively, a forging job-shop scheduling system based on quality of service was presented. Through analyzing the production mode and main processes, the key indicators affecting the quality of job-shop scheduling were proposed. Furthermore, the architecture of a forging job-shop scheduling system was established and the main functions were discussed. Finally, the data structure and the relationship between the tables were described detailedly.