Implementation of Lean Manufacturing Principles in a Colombian Machine Shop: Layout Redesign and Theory of Constrains
This paper describes the Lean Manufacturing strategies, implemented in a medium-sized machine shop located in Bogotá, Colombia, that led to major improvements in productivity. The main objectives of this project were to better use the plant capacity and to reduce overtime expenditures. The project consisted of three stages. In the first stage the plant layout was redesigned using a Group Technology philosophy for manufacturing cells. In the second stage, the precise number of resources (machines and workers) was established at each manufacturing cells using a Theory of Constraints (TOC) approach. In the third stage a training program for the employees was implemented. The consequences have been significant: the plant layout was reorganized, halls were opened, and the shop floor is now cleaner, more pleasant and more comfortable. Overall productivity increased about 15% in terms of throughput, and defect rates were reduced 20%. Workers are now specialized and more willing to learn and participate in their work procedures. Additionally, according to the production manager, the relationship between workers and management has greatly improved.
KeywordsIdle Time Process Route Production Schedule Shop Floor Cellular Manufacturing
Santiago Piñeiro, mechanical engineer, Universidad de los Andes, Bogotá, Colombia, firstname.lastname@example.org.
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