Delft University of Technology
Faculty Mechanical, Maritime and Materials Engineering Transport Technology / Logistic Engineering
D.J. Wijnschenk Voorraadbeheer in een distributie-omgeving. Een generiek conceptueel model en feitelijke toepassing voor Bührmann-Papyrus N.V.
Masters thesis, Report 93.3.LT.4134, Transport Technology, Logistic Engineering.
Bürmann-Papyrus is a Belgian company which, among others, includes a paper merchant. In this company a new, integrated computer package was put into use in January 1993. However, a sound support for stock control was not included. There was a need to develop a new stock control system, in which an order policy had to be sought which could operate optimally as far as costs were concerned.
This report describes of a generic, conceptual model for stock control, in which topics including demand classification, demand forecast, and order models have been developed. This generic, conceptual model has been chosen in order to arrive at an optimal stock control system, which is
independent from the present situation at Bürmann-Papyrus. Eventually, after an extensive analysis of data, it has been indicated in which way the various parts of the stock control system at Bürmann-Papyrus have to be completed. An important aspect, which was concluded from the conceptual model, is the necessity of a good control system, that enables a continuous checking of the stock. This checking forms the basis of the entire stock control system, and should both easily and efficiently be executed. Developments in stock control show a reduction of the number of suppliers, curtailment of the delivery time, an increase of delivery reliabilities, a rise in commencing quality, and a reduction of order quantities. The recording and control of agreements with suppliers is of great importance. In the conceptual model this is clearly demonstrated. The results of the 1992 data analysis demonstrate that a reduction of the range of products does not seem unwise. Reduction of the range of products should not only result in the deletion of products from the catalogue, but should also result in the removal of products from the warehouse. Adjustment of the order position on the basis of a certain service level, instead of the present adjustment, will lead to a considerably better service level for a large number of products.
The developed stock control system makes use of demand forecasts for certain future periods and for estimated deviations of the forecasts. With the aid of these forecasts the optimal order volume will be established. Requisite parameters for this system are: delivery time, deviation of delivery time, cost factors, and service level. Practical introduction of the recommendations is only possible in stages. Immediate results with respect to the stock control will be possible by adjustment of the product range, a different calculation of the order position, the specific attention paid to a small percentage of the product range, the introduction of a control system and a graphical presentation of the data.
Reports on Logistic Engineering (in Dutch)
