According to Industry 4.0 the process of digitization in manufacturing companies has advanced to the virtualization phase. The final state should be a complete virtualization of the production plant. However, virtualization has a high demand for innovation. This article summarizes the findings of the implementation of the "Digital Twin" methodology in a real manufacturing company. The main topic is virtualization of heavy machine tools of Skoda Machine Tool Co. For the virtualization are used modern software tools Siemens NX, Mechatronic Concept Designer, Simit and VNCK kernel.