Theoretical discussion of the concept of wastes in the Toyota Production System: Introducing the throughput logic of the Theory of Constraints

Abstract

This study presents a theoretical reflection about the possible impacts on of the Theory of Constraints (TOC) indicators caused by the Seven Wastes in the Toyota Production System (TPS) and a type of waste which is not included in that context. It refers to the 'waste due to unsatisfactory definition of product mix' influenced by the use of inappropriate methods to formulate the product mix. Therefore, a conceptual neologism is introduced, identified as the "Pergas" to demonstrate the overall gain waste derived from this practice. The need to reduce process waste is due to the fact that no value is added to the product and the cost increase putting at risk, in some situations, the organizational competitiveness. Similarly, the fight against "Pergas" leads to an increase in the indexes monitored by the Global indicators of TOC, through the creation of a mix of products that contributes to the company's goal. A structural framework was developed relating the seven Wastes addressed in the TPS and TOC indicators, which will provide subsidies to support the relations that cause impacts and will enable the proposal of improvement actions focusing on reducing the impacts presented.