In order to evaluate the resources and environmental load of typical sand casting process more intuitively and effectively, a comprehensive evaluation index is proposed based on the evaluation results of resources and environmental load. The calculation process of comprehensive evaluation index is as follows:
(1) Select the evaluation object, determine the system boundary, and use inventory analysis to obtain the input and output raw data in the life cycle process.
(2) According to the evaluation index system of typical sand casting process resources and environmental load, the life cycle assessment results are calculated, and the evaluation values of each index of the process are obtained.
(3) Normalize the evaluation results according to the benchmark values of each indicator to obtain the dimensionless evaluation results of each indicator.
(4) According to the weight of each index and the dimensionless evaluation results, the comprehensive evaluation results are obtained by using the linear weighting method. The comprehensive evaluation method is as formula.
Where: CIj – comprehensive evaluation results of the jth typical sand casting process, SERi, j and α i. J is the normalized evaluation result and index weight of the ith index of the jth typical sand casting process.
(5) According to the comprehensive evaluation results, the typical sand casting process resources and environmental load are compared and analyzed, the results are explained, the links with greater impact on environmental load are identified, and the improvement suggestions are put forward.