Remanufacturing Evaluation And Active Remanufacturing Time Determination Of Concrete Pump Truck Boom System

Construction machinery usually faces problems such as the weight of the whole machine,the consumption of materials,and the environmental pollution after decommissioning,the five development concepts proposed by China and the China Manufacturing 2025 plan put forward the requirements for sustainable development of the machinery manufacturing industry,remanufacturing is a series of technical measures or engineering activities for the repair and transformation of used mechanical and electrical products,with significant energy conservation and festivals.The characteristics of materials and environmental protection are effective ways to solve the problems faced by used construction machinery.The remanufacturing of construction machinery and the research on remanufacturing time points based on performance improvement are important issues in the development of the remanufacturing industry,and the support of relevant theories and practical support tools is urgently needed.In this paper,the remanufactured concrete pump truck boom system is taken as an example.The following research work is carried out around the remanufacturing evaluation of waste electrical and mechanical parts and the starting point of active remanufacturing of mechanical products based on maintenance:(1)Based on the analysis of the structural composition of the concrete pump truck and its boom system,the important part structure and the main failure modes,the functional level of the boom system is decomposed from the perspective of remanufacturing;the influence of waste mechanical and electrical products is analyzed.Remanufacturing factors,and related parameters affecting these factors during remanufacturing implementation and their acquisition,determine the remanufacturability evaluation process of the boom system.(2)The life assessment and prediction of remanufactured parts is a prerequisite for implementing remanufacturing and ensuring the reliable quality of remanufactured products.The failure behavior and life assessment of the construction machinery meet the Weibull distribution.Most of the failure behaviors in construction machinery meet the Weibull distribution.The average life of the boom is determined by the Weibull distribution and the service time of the boom system in the ECC system.The data samples are continuously expanded to determine the effective value and pass under different working conditions.The finite element fatigue life analysis of the boom system is compared with the average life of the Weibull failure distribution to improvethe average life results and the validity of the parameters evaluated by the Weibull failure distribution.The reliability of the boom system is determined by the reliability function of the two-parameter Weibull distribution,and the boom system can be evaluated for remanufacturing.(3)According to the specific process flow of the boom system remanufacturing,the remanufacturing evaluation index system of the boom system was established,and the relevant parameters of technical feasibility,economic feasibility and environmental feasibility were analyzed in a deeper level.The data determines the specific values of the relevant parameters,uses AHP to determine the weight of each factor and indicator,determines the membership degree by the specific value of each parameter,and obtains the final evaluation score of the boom system,which is evaluated by the benchmark set by the expert.The score comparison is used to determine the remanufacturability of the boom system.(4)For the point-in-time study of performance upgrade and remanufacturing,the concept of active remanufacturing based on update and maintenance is proposed,that is,the time when remanufacturing is started when components start to enter a stable failure period.At this time,the performance of mechanical components begins to stabilize;Based on the failure distribution density function of the same mechanical parts,the mechanical system failure time model based on the update and maintenance is established.The relationship between the system component failure rate and the component failure distribution time parameters is simulated.The system failure probability and time approximation are given.The mathematical model calculates the system failure stabilization time point based on the approximate mathematical model,which is the active remanufacturing time point based on the update maintenance.