Research On Life Cycle Cost Evaluation Method Of Bogie

Bogie is key component of railway vehicle. And its cost is also an important part of railway vehicle cost. Reducing bogie life cycle cost effectively will greatly reduce railway vehicle cost. Traditional cost evaluation methods mainly include analogy evaluation method, parametric evaluation method, engineering evaluation method and expert evaluation method. Each method has respective advantages, also has disadvantages. Therefore, aiming at the disadvantages of traditional evaluation method, this paper proposed a new method for the prophase of train-set bogie life cycle. This method is a combination of three methods which are expert evaluation method, TOPSIS method and support vector machine method. This paper proposed a new method for the anaphase of train-set bogie life cycle. This method is a combination of unascertained number analysis method based on expert evaluation method and grey system theory method.For development phase, using experts’ experience built evaluation criteria of quantitative indexes which contain reliability, mean time between failures, service life and cost. For manufacturing phase, using experts’ experience built evaluation criteria of non-quantitative indexes which contain material quality, processing equipment automation level, employee comprehensive productivity and cost. Eight experts were invited to give their scores based on the evaluation criteria. The scores would be used as the original data of TOPSIS method. Then according to the actual situation, the best solution and the worst solution would be selected. The closeness function of TOPSIS method would be used as the objective function of support vector machine method. Finally, the prediction results would be output. For operation and maintenance phase, the cost is produced year by year. But in our country the similar referential product put into operation only few years. The data could be collected is particularly scarce. So at this phase only unascertained number analysis method based on expert evaluation method could be used. Through the operation and maintenance cost situation in recent years of the similar train-set, the operation and maintenance cost of the first five years would be evaluated. Then the first five years evaluation would be used as the known information of grey system theory method. And after the 5th years, the operation and maintenance cost of each year in train-set bogie life cycle would be obtained by the grey system theory method. Finally, because the evaluation method is mastered, using Visual C++ as programming tool based on MFC frame made the life cycle cost evaluation software. All phases would be combined by this software effectively. And each phase is no longer a single phase of the life cycle.It could be known from four cases in this paper that the cost of development phase was about 550,000 ￥ to 570,000 ￥, the cost of manufacturing phase was 980,000 ￥ to 1,000,000 ￥, the cost of operation and maintenance phase was 2,552,000 ￥, the cost of abandoned disposal phase was 74,000 ￥. The evaluation result showed that the cost of operation and maintenance phase accounted for about 61 percent of the total life cycle cost. However, the cost of this phase is influenced by the bogie performance directly. Therefore, when evaluated cost is less than the original cost, the cost of development phase could be increased appropriately. Then the bogie performance will be improved and the operation and maintenance cost will be reduced. Thus, the life cycle cost could be evaluated under the condition of lack of data and information. It is not only beneficial to optimize the bogie performance, but also significant for the cost control.