PROGRESS TOWARDS LEAN THINKING THROUGH IMPLEMENTATION OF TRADITIONAL VALUE STREAM MAPPING OF MANUFACTURING PROCESS. CASE: VILPE OY.

Abstract

Use of Lean philosophy has resulted in many benefits for the companies, including reduced lead time, improved quality of products, greater productivity and smoother operations. Lean consists of many tools and methods which help to minimize inefficiency for example through identification and elimination of 8 types of waste. One of Lean tools called Value Stream Mapping (VSM) was applied in case company in order to discover areas for improvement of the process within VILPE Oy. The objectives of the study were to identify what wastes can be found in the company through implementation of traditional VSM and suggest methods of reduction or better control over found waste.

VSM tool can be combined with other seven mapping tools for better identification of wastes. However, as wastes in the form of transportation and motion were identified in the company before – only traditional VSM was applied in this study. In addition, future value stream map is not created, because standard improvement methods usually utilized after implementation of VSM are not used. Instead as inventories, especially end-product (finished goods) inventory, were discovered to be main waste, further analysis of inventories was performed. Analysis revealed that end-product inventory is anticipation inventory. Solutions for better control of anticipation inventory are formed based on theories of inventory management and demand forecasting. One solution suggests to use numbers forecasted through Holt-Winters model in reorder point calculation, while another solution suggests more simple way to consider seasonality in reorder point calculation. Currently reorder point is calculated based on average demand, what is not suitable for products with seasonality. Adjustments in reorder point together with improved qualitative forecasting are suggested as measures for better control over anticipation inventory.