Modeling And Analysis Of Carbon Emission In CVT Gearbox Manufacturing Process

The continuously variable transmission(CVT)has advantages of better fuel economy,continuous power output and simple mechanical structure,which is widely used in the automotive industry.However,China's automobile manufacturing technology lack of core competitiveness,in the face of continuous increase in the annual production of the car CVT gearbox,the ensuing environmental problems inhibit the development of the CVT gearbox manufacturing industry.Therefore,this paper studies the carbon emission in the CVT gearbox manufacturing process,and solves the environmental problems of the manufacturing process from the root causes,which is of great theoretical and practical value for realizing the sustainable development of the industry.In view of the carbon emission assessment of CVT gearbox manufacturing process,this paper does some work as follows:(1)Based on the theory of product life cycle assessment(LCA),the advantages and disadvantages of different carbon emission assessment methods and their application scope are analyzed synthetically.The carbon emission assessment method applicable to CVT gearbox manufacturing process is put forward,which is aiming to realize the purpose of accurate assessment of carbon emission in CVT gearbox manufacturing process.(2)The carbon emission characteristics of CVT gearbox manufacturing process is analyzed,the system boundary is determined and the basic carbon source types within the boundary are defined,and the basic carbon source calculation formulas are established by PAS 2050 carbon emission coefficient method.The process of carbon emission in the CVT gearbox manufacturing process is complex and the emission links are large,meanwhile the energy and material consumption are large.Considering the characteristics of the carbonemission in CVT gearbox manufacturing process,the hierarchical relevance analysis(HRA)theory is used to ensure the normality of the calculation process and the accuracy of the calculation results.Thus,the carbon emission assessment model of CVT gearbox manufacturing process is built,and the total carbon emissions in CVT gearbox manufacturing process are calculated.By comparing with the results of the example,it is verified that the model has feasibility.(3)Taking the Nissan JF011 E CVT gearbox as the specific research object,the established carbon emission assessment model is applied and the carbon emission data of the CVT gearbox manufacturing(including new manufacturing and remanufacturing)process are calculated by field survey.The analysis of carbon emissions results show that the total carbon emissions are mainly from the material carbon emission,and the material reuse ratio has the greatest impact on the total carbon emissions.(4)The carbon emissions results of Nissan JF011 E CVT gearbox new manufacturing/remanufacturing are compared comprehensively,the data show that the remanufacturing process has a significant advantage in reducing material consumption and carbon emissions,which verifies the environmental benefits of remanufacturing products.This paper effectively solves the carbon emission assessment problem of CVT gearbox manufacturing process through the establishment of a reasonable carbon assessment model,the model is applied in practice and the major carbon emission sources and carbon emissions factors are exhumed deeply,so the research is of great significance for the realization of the high efficiency and low carbon target of the CVT gearbox manufacturing process.