Application of lean manufacturing using value stream mapping (VSM) in precast component manufacturing: A case study

Abstract

Prefabrication of structural concrete elements and assembly at site offers advantages such as reduction in construction time, improved quality and reduction of material wastage. These advantages depend on standardization and good organization of work at the precast component manufacturing unit. The need in a precast factory is to ensure a smooth and delay-less manufacturing process so that wastes can be eliminated and better productivity can be achieved. The aim of this research paper is to apply lean principles and lean thinking using value stream mapping to reduce the processing time and increase the production in a precast component manufacturing unit. A precast component manufacturing unit in Chennai was chosen for the case study. The precast plant was visited to understand the entire manufacturing process. Value stream Map (VSM) of the manufacturing process was created using Lucidchart software. The wastes were identified based on seven wastes of lean. Changes were proposed to eliminate the waste which included change in layout of the manufacturing unit and handling devices. Future state map was created for the improved manufacturing process. Comparison of cycle time and lead time was made for before and after the proposed changes. The lead time decreased from 1102 to 739 min and the production increased from 33 units to 40 units per day. Also, it is found that the efficiency and effectiveness improved by 49% and 21.2% respectively. The study demonstrates that it is possible to achieve improvement in production of precast component manufacturing unit using lean principles. Improvements in the reduction of lead time, reduction of waste and increase in production are achieved with simple techniques.