Research On Integrated Optimization Of Process Planning And Scheduling For High Efficiency And Low Carbon

With the deterioration of the global environment,the greenhouse effect is becoming more and more serious.The traditional manufacturing development model with large energy consumption,high material consumption and serious pollution has gradually transformed into the low carbon manufacturing.The optimization of carbon emission in the manufacturing process has a great effect on reducing the waste of resources and improving the energy efficiency.So there is an inevitable trend of low carbon manufacturing with the development of manufacturing industry.Process planning and scheduling are two important parts in the manufacturing process.There are some integrated optimization researches of process planning with fixed cutting parameters and scheduling which could further reduce carbon emission in the manufacturing process than separated optimization.According to the influence which process planning(machining method,process resources,cutting parameters and process routes,etc.)and scheduling(machine tools and machining sequence of workpieces)have on carbon emission in the manufacturing process and completion time.A multi-objective integrated optimization model of cutting parameters,process routes and scheduling for reducing manufacturing carbon emissions and completion time is proposed.Processing time of all workpieces and idle time of machine tools processing two adjacent workpieces are taken into consideration in completion time.The carbon emission caused by energy consumption,cutting tool,cutting fluid consumption and carbon emission caused by machine tool in ildle processing two adjacent workpieces are included.A hybrid multi-objective Grey Wolf Optimizer(HMOGWO)is designed to solve this integrated optimization model.Since cutting parameter optimization is a continuous optimization problem,and selection of process routes,machine tools and scheduling optimization are discrete optimization problems.Any solution in the search space consists of for parts: process routes,cutting parameters,machine tools and machining sequence of all workpieces.Process routes,cutting parameters,machine tools and machining sequence of workpieces are mutated separately.Process routes,cutting parameters,machine tools of one workpiece are crossovered simultaneous and machining sequence of workpieces is crossovered to get a better optimization.Finally,multiple workpieces with multiple processes processed on multiple machines are taken as an example.Completion time isn’t directly connected with carbon emissions in manufacturing processes.The composition of carbon emission is analyzed.Carbon emission caused by energy consumption of machine tools and consumption of cutting-tools are high,the former is relatively stable,and the latter varies greatly.Based on the integrated optimization of process planning with fix cutting parameters and scheduling,the integrated optimization of cutting parameters,process routes and scheduling is compared with the integrated optimization of process routes and scheduling that cutting parameters are optimized in advance.The integrated optimization of cutting parameters,process routes and scheduling is is illustrated that it can further reduce carbon emission in the manufacturing process and completion time.