Simulation of large precast operations

The paper presents the analysis of the optimization for the production of precast pieces in a workshop with the help of simulation to obtain several working alternatives. The main objective is to improve the productivity and therefore reduce the production costs. Since the analysis was done with the workshop in full production, it was not possible to plan for changes that would stop the production. A first model was designed, duplicating the already established production method, which had a production rate of 75 pieces per turn. The results obtained were similar to the real method. The analyzed alternatives were based on progressive changes to the initial model: assigning tasks to the personnel, homogenizing the number of in-process pieces for the successive phases, and schedule variations. The simulated production rate of the last model was 108 pieces per turn, with a productivity increase of 44%. Implementing the solution proved the excellence of the model when the forecasted production rate was obtained after only a few days and with absolute regularity. Previous to the description of the case, the paper presents the changes that Dragados implemented to adopt simulation as a tool to improve productivity. Dragados is a group of more than 50 firms that were born after a process of intense diversification from its main purpose, construction