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A modified model was presented for describing corrosion fatigue crack growth rate of aluminum alloy accurately. Considering the local damage around the crack tip is more reasonable for accelerating crack growth rate under corrosive environment, a damaged influence factors which characterize the damage degree of local damage near the crack tip has been introduced to revise the corrosion fatigue crack growth rate, and the experimental results are in good agreement with predictions of amendment fatigue crack growth rate model. The proposed model based on damaged influence factors is reasonable, and proposed a theoretical reference for aluminum alloy damage tolerance analysis.

The fatigue crack propagation behavior of the prior corrosion 2A12 aluminum alloy fastener involving a central hole was investigated. The virtual crack closure technique (VCCT), is straightforward and not sensitive to the FEA mesh size, was carried out to calculate strain energy release rate and SIFs of AA 2A12 under different stress levels and corrosion years. Based on the VCCT, the simulation carried out to analyze the corrosion fatigue crack growth behavior. It was proved to be convenient to simulate the crack propagation life and the predicted crack growth curve was in good agreement with the experimental results.

This paper presents an indoor positioning system based on RFID, which introduces electronic tag assisted positioning, according to the plurality of the electronic tags which are arranged in the target area as equilateral triangle, and the reader reads the information and Received Signal Strength Indication (RSSI) within its reading range. Sampling and calculation of the positioning result is controlled by the core circuit. Experimental results show that the indoor positioning system has excellent positioning accuracy, with high efficiency and low cost.

The door operator in metallurgical equipment is a spatial 6-bar linkage mechanism. The numerical model of motion and force of the mechanism was developed and the numerical solution was applied. A computer simulation was implemented. There is a high level of consistency between the solution and simulation. The torques required on driving crank have been studied. The influences of the self-lock conditions on the crank length and con-rod length have been explored. The effects of the length of crank and con-rode on the needed maximal torques of the crank have been studied, too. And the kinematics analysis attributes the lightening design of the slider structure on the basis of considering the sliders rigidness and intensity.

The two-dimensional O-ring seal nonlinear axisymmetric finite element model are established which is used for swinging hydraulic cylinder. Some factors influencing rubber O-ring sealing performance were taken into account, such as rotating shaft diameter, O-ring seal section diameter. The results indicate that when medium pressure is zero, the two factors influence Von Mises and maximum contact stress of sealing face greatly. Under medium pressure (P=10Mpa), the two factors have a little influence to Von Mises and maximum contact stress.

The ladle is an important equipment of the metallurgical industry. Distribution of thermomechanical stress in linings has an essential influence on its life, and the size of its life-span influences the economic benefits of the iron and steel enterprise directly. Two-dimensional model of ladle based on law of finite element method is built, and the influence of thermal conductivity, thermal expansion coefficient, elasticity coefficient and thickness of work lining on ladle stress field are discussed. The calculation results indicate that stress increases with the increase of thermal conductivity, thermal expansion coefficient and elasticity coefficient and decrease of thickness.

Coke combustion process, the constant proportion of the combustion air-fuel ratio control results in low combustion efficiency and fault-prone, difficult to adapt to changes in complex working conditions. Application of intelligent technology of case-based reasoning, fuzzy control, proposed for intelligent energy saving air-fuel ratio control method. Based on current trends in working conditions and combustion process in case of failure, predict the typical faults with case-based reasoning technology to the combustion process. On this basis, through case-based reasoning algorithm realize the real-time air-fuel ratio correction. Based on fuzzy-PID temperature cascade control we can obtain the appropriate flue gas flow and flue suction and realize the stability of the combustion process to achieve optimal control.

According to the requirements and characteristics of air compressor control systems in the process of air separation, an intelligent control method based on the fuzzy PID was proposed. Through simulating the designed control method, it is concluded that the control effect was extraordinarily satisfactory. It can offer a certain meaning of guidance and reference for the control of other equipment in air separation systems.

The sealing contact pressure is critical in determining the film thickness of elastohydrodynamic lubrication (EHL) on the seal. Contact pressure in sealing surface of non-rectangular section vane seal was obtained via FEA, and the polynomial equation of the contact pressure distribution was fitted with regression analysis. Therefore, the numerical model for the EHL film thickness can be developed and solved. Typical results of film thickness distribution and frictional force for the vane seal at room temperature were obtained. The EHL film thickness distributions follow the variation of the related contact pressure, and the sliding speed is also significant on the average film thickness and the hydrodynamic friction.

The air compressor system is a time-varying, delay and nonlinear complex system, it has a very important sense to ensure that the supply pressure is stable in the compressor control system. According to the working characteristic of air compressor system, the fuzzy control theory, as one of the modern control theories, was applied into the constant pressure control system to design a fuzzy pressure controller. The simulation results show that the controller was more convenient and effective; it has certain directive significance and reference for the other parameter’s control of air compressor system.

In accordance with the main flow characteristics of steel and iron production process, some problems are analyzed coming from the making, performance and feedback of the production planning of iron and steel business enterprises in this paper. By using operation research theories and genetic algorithms, one advanced planning model of iron and steel productions suitable of various circumstance and environments is established to set up on the factor of the segment and environment variety. Penalty function is adopted in the course of getting solution. These parameters of scale of father population, crossover probability, mutation probability and penalty factor are combined and optimized. At the same time, to improve these algorithms and the solution process actually, some optimized models and projects were put forward from some plans on the basis of collecting information. It accords with the actual conditions of this enterprise basically that the optimization solution to production plans of real iron and steel enterprise by using the algorithm.

Green manufacturing is an effective way of realizing the sustainable development strategy. From the view of evolution of production chain and goods value, energy-saving, cleaner production and green manufacturing of iron and steel industry is discussed and the importance of system optimization of steel manufacturing process is stressed. Connotation of green manufacturing for the iron and steel was explained, the function of steel production process for green manufacturing was discussed and the content system of implementation of green manufacturing for the iron and steel enterprise was established. Finally the steel production process was optimized. The function of iron and steel manufacturing procedure are broaden-manufacturing function of steel product, function of energy conversion and function of waste recycling, which will enhance enterprise’s competitiveness and sustainability.

In order to improve the level of control and management of coke oven, the research on control and management integrated system is carried out. In modern advanced control system of coke oven, the control scheme of feedback combined with feed-forward, and control merged with management is widely used. The integrated control and management system of coke oven is introduced systematically, including the system model, production planning and management, heating control system, the model and method of evaluating temperature, intelligent combustion control and the pressure control gas collector of coke oven. It is pointed out that the integration of control and management is the developing orientation of coke oven control system.

According to the characteristics and control demand of coke oven, research on intelligent control of coke oven production process was carried. Firstly intelligent control structure of coke oven production process was established. Then intelligent control of blending coal, collecting main pressure, combustion and heating intelligent control of coke oven were discussed simply, while production planning and scheduling was discussed in detail. The control principle of combining the intermittent heating control with the heating gas flow adjustment was adopted, and fuzzy compound control was proposed to establish heating intelligent control strategy and model of coke oven, which combined feedback control, feedforward control and fuzzy intelligent control. Production planning and scheduling of coke oven were optimized by using dynamic programming and genetic algorithm. The practical running indicates that the system can effectively improve quality of coke and decrease energy consumption, stabilize production of coke oven, and has great practical value.

With the development and application of the Internet and Intranet, it shows that the response of the traditional manufacturing model to the information lags behind the change. Based on the computer technology, web technology and modern communication technology, the information flow of networked manufacturing system can be transferred timely among virtual alliance regardless of regions. So social manufacturing resource can be used fully. In order to share timely the information and optimize the social manufacturing resource about designing and producing car wheel hub, a solution to establishing networked manufacturing system of car wheel hub based on ASP and SQL Server was put forward. According to detailed analysis the process of design information transferring and the hub designing, a prototype networked manufacturing system of car wheel hub had been developed. It has very great practical value.

At present, iron and steel enterprise develops towards the direction with many procedure, many process, many variety and many specification, and reaches hundreds and thousands of product series and product mix, how to plan, organize and control steel production, production schedule of its product line is a key issue. Mixed production plan model of product line can be summed up in a kind of network flow plan issue. According to the characteristics of network flow plan issue, the production schedule model of product network flow is established through describing digraph-connected graph of production procedure of iron and steel enterprise. Its goal function is the biggest profit of production of product line, restrain functions are the capacity limiting conditions, the balanced condition of the middle peak point, capacity restrain with supply and sell production and restrain with enterprise procedure process resources. Several key resource production procedure processes are chosen to calculate by using standard library function of the Matlab7.0 genetic algorithm toolbox to program. Penalty function is adopted in the course of getting solution. These parameters of scale of father population, crossover probability, mutation probability and penalty factor are combined and optimized. Results indicate that goal value reach convergence after finish 119 iterative operations. It accords with the actual conditions of this enterprise basically that the optimization solution to production plans of real iron and steel enterprise by using the algorithm.