Research On Optimization Decision Of Remanufacturing Process Scheme Of Used Machine Tools With Multiple Objectives

Remanufacturing is a high-level form of resource recycling and becomes an important development direction for advanced manufacturing models,which it plays a catalytic role in alleviating energy crisis and resource shortages.The remanufacturing of used machine tools as a key research object in the remanufacturing field,it is a course of taking remanufacturing technology to repair worn-out machine tools and restoring their initial behavior.However,the remanufacturing carbon emissions and process time of used machine tools are subject to differences due to the degree of damage of used machine tool parts.As a result,the decision of the process scheme is uncertain,thus restricting the progress of the remanufacturing of used machine tools to standardization and scale.This thesis takes the remanufacturing of used machine tool parts as the research object,and establishes the carbon emissions and process time model for the remanufacturing of used machine tool parts at various stages.Based on the correlation between the damage of the used machine tool parts and thecorresponding process routes,the thesis achieves the optimization decision of used machine tools with multiple objectives by finding the order of remanufacturing of used machine parts and the combinations of process equipment.The thesis is supported by the Natural Science Research Foundation Grant Program of Anhui Province,and makes a study on the optimization decision of remanufacturing process scheme of used machine tools with multiple objectives.The main research contents are as follows:First of all,the thesis summarizes the literature on the remanufacturing of used machine tools,and finds it focuses on two aspects.The first aspect mostly focuses on closed-loop supply chains,carbon tax policies,recycling behaviors,and production models for remanufacturing of used machine tools,and the research conclusions are relatively complete.The second aspect mainly analyzes the impact on the remanufacturing workshop scheduling and process routes from the perspective of the uncertainty of the damage of used machine parts,and seeks the best remanufacturing process routes under the goal of production cost and process time.However,research on such issues does not involve the analysis of remanufacturing carbon emissions and also has not optimized the sequence of process of used machine tool parts and the combinations of process equipment.Therefore,according to the literature shortages,this thesis proposes the research on optimization decision of remanufacturing process scheme of used machine tools with multiple objectives.Secondly,the thesis introduces the time Petri net from the point of view of the uncertainty of the damage of used machine tool parts.Describing the differentiation of the remanufacturing carbon emissions and process time caused by the uncertainty of the used machine tools and establishing a remanufacturing process model for used machine tools based on the time Petri net.Then,based on the time Petri net remanufacturing process model of the used machine tools,fuzzification and rule-based reasoning are used to evaluate the damage of the used machine tools in this thesis.Through the analysis of CO2 release at each stage of the remanufacturing of used machine tools,the energy-reduction method is used to quantify the remanufacturing carbon emissions.Based on the analysis of the remanufacturing process time of used machine tools,the thesis establishes a multi-objective optimization decision model for the remanufacturing process of used machine tools.For this model,the genetic algorithm is used to solve this problem,so as to find the optimal solutions of the remanufacturing process sequence and the combinations of process equipment under the low carbon and short-term.Finally,an example verification of the used spindle remanufacturing process scheme is carried out,and the genetic algorithm is used to seek the target solutions of the lowest carbon emissions and the shortest process time for the used spindle remanufacturing,and the remanufacturing process sequence and the combinations of process equipment of the used spindle parts are arranged.The result proves thevalidity of the decision model and the feasibility of the algorithm.The research provides theoretical support for the optimization decision of remanufacturing process scheme of used machine tools,at the same time,it gives an example for remanufacturing enterprises to implement low-carbon and short-time processing.