Machine overhaul refers to the process of thoroughly inspecting, maintaining and repairing a machine, plant or equipment to improve or restore its performance, reliability and service life. This may involve repairing or replacing parts, renewing wearing parts and making technical improvements.

Retrofitting refers to the updating or modernization of an existing machine or system in order to equip it with new functions, technologies or specifications. This can include, for example, the integration of new control systems, sensors, safety functions or efficiency improvements. The aim of retrofitting is to improve the performance, safety, efficiency or compatibility of the machine without having to replace the entire system.