Digital twins is a recent paradigm. It creates an entangled link between the physical system and its digital twin. The digital twin has obviously no sense without the existence of the physical system, but the physical system highly depends on the digital twin. This concept opens many new challenges and opportunities. Authors contributed to the construction of a digital twin architecture to manage a shop floor. The experience concerns a complete shop floor. To reach the status of digital twin, it was expected to reach simulation capacities and a complete digital chain to ensure the real time synchronisation of the real world with the underlying model which is the core component of the digital twin. A bottleneck was to create a coherent information system connecting information coming from various sources (MES, Machine Design, ERP, etc.), then to propose first functions to demonstrate the added value of this digital twin; here a production simulation was expected within a visual 3D realistic representation of the shop floor. The simulation uses data directly captured from the shop floor to support better decision making.This paper presents the developed digital twin and its added value respect to production needs. It focuses on key performance indicators synchronisation as observed in the physical world and the impact on anticipation of the various futures depending on production decisions. It reports a first step of a digital twin deployment.