Materialförsörjning: Effektivisering för ökad leveransservice och minskad totalkostnad
Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
Materials and components are essential for all manufacturing companies to manufacture their products and meet customer requirements. Large order quantities contribute to higher inventory levels and increased holding costs but allow high delivery service. Small order quantities contribute to lower holding costs but there is a risk that shortage arises that may cause disruptions in the manufacturing process. Changed conditions, such as increased demand or delayed delivery from suppliers, make it even more difficult for companies to meet customer requirements. It requires constant tradeoffs between resource utilization, working capital and delivery service to find the best overall solution. The purpose of this study was to examine how the supply of material can become more efficient to achieve enhanced delivery service and reduced total cost. More specifically the study focused on how demand can be forecasted, how order quantities and time between orders can be calculated and how uncertainties can be managed. A case study has been conducted at Lundqvist Trävaru AB in Öjebyn, Sweden. The company manufactures wooden buildings such as garages, cottages and similar according to customers wishes. Wood, also known as timber, is their most important raw material for the products. Specially treated wood for roof trusses (C24) are used for all buildings and standard panel represents over 70% of all timber used for panel. In the current situation Lundqvist Trävaru AB purchases C24 and standard panel in large order quantities and the average inventory levels are high, for example the average inventory level of C24 is equivalent to more than half of its annual consumption. Collection of primary data was conducted through interviews and observations, and secondary data has been collected from the company's sales history and accounting. Empirical data combined with the theoretical framework has been the basis of the analyzes which the study's findings and recommendations are based on.The study shows that Lundqvist Trävaru AB can reduce their total cost of C24 and standard panel by 82% and 41% respectively. The study only included one case and therefor its results cannot be generalized. The work methodology and the analysis can be applied to other manufacturing companies in efforts to streamline its supply of materials to achieve enhanced service delivery and reduced overall cost. The working methodology and analyzes are presented in the study's conclusion and can be summarized in the following activities: 1. Mapping of current materials supply and related activities 2. Forecasting of demand taking into account identified demand patterns 3. Lot sizing with an appropriate method 4. Design of safety stock according to the required level of service and the prevailing uncertainties. A suggestion for further study is to examine whether the lot sizing method Wagner & Whitin algorithm always will result in the lowest total cost, or if different lot sizing methods are preferred for different demand patterns.
Place, publisher, year, edition, pages
2013. , 95 p.
Social Behaviour Law
Samhälls-, beteendevetenskap, juridik, Materialförsörjning, prognostisering, partiformning, säkerhetslager
IdentifiersURN: urn:nbn:se:ltu:diva-53131Local ID: a323278e-0a02-43f8-82ad-4678d997ccacOAI: oai:DiVA.org:ltu-53131DiVA: diva2:1026505
Subject / course
Student thesis, at least 30 credits
Industrial and Management Engineering, master's level
Validerat; 20130611 (global_studentproject_submitter)2016-10-042016-10-04Bibliographically approved