Materials and Spare Parts Management for Gas Pipelines

The challenge for materials and spare parts management is to keep an economical inventory level and assure reliability to end-users. Another challenge is to have end users committed to the management model and procedures. The usual models call for re-order points and statistics analyses that do not fit the normal demand profile of pipelines. The proposed model works in committees by equipments or installations (as compressor stations, city-gates, etc.). The committee defines the necessary level of reliability for each material or component, estimated demand, normalized specification, etc. The Stock Base model supplies the statistical support for defining the quantity to maintain during the leading time plus a standard interval between semiannual or annual analyses. The model combines the most important concepts practiced by material management: Pareto’s Principle to indicate the economical standpoint to be considered in the analyses, statistical concepts to indicate the level of reliability required (accepted interval between two consecutive non-stock situation), traditional methods of material management (as the replenishment stock level) and the most important: the end users recommendation. The main results of this model are: low inventory levels, non-repetition of items in stock, different treatment for classes A, B and C items, combination of economical and operational importance resulting in reliability and stock investment reduction.