Automatic painting plant in Merlo SpA: digitalization of pre-assembly workstations, plant interconnection and tracking of material production flow

The Merlo Group, a technological leader company in the design and manufacture of telescopic handlers, is gradually starting a process oriented towards digital transformation, with high investments in robot applications, innovation, automation projects and new technologies in line with Industry 4.0 optics. The company has recently invested in the installation and commissioning of a new automated paint shop, the VER50, for the liquid electrostatic painting of Merlo telehandlers’ components by anthropomorphic robots. The VER50 plant will entirely replace the previous manual paint shop, so the entire painting process of axles, tie-rods and hydraulic cylinders will change from manual to automatic, thus increasing the machines' daily production and achieving component repeatability and a higher level of standardization. The VER50 project aims to digitalize the manual workstations for the assembly of mechanical components and the processes upstream of the painting phase, hence optimizing the traceability of material flow within the pre-painting processes and streamlining the passage of data at the IT level. A new application program, through a user-friendly interface, will help operators during the assembly phase by displaying the components to assemble or test according to the production sequence and giving the possibility to declare the work done and call Merlo Logistics for the transport to the paint shop. Developing the application has required the analysis of all the functional logic and requirements for allowing its correct functioning as well as the study of the pre-assembly process in the various workstations and the differentiation of the main production flows. The interconnection between the paint shop system and the Merlo system consists of various exchange data flows and enables real-time monitoring of the painting process, thus allowing for component tracking and distinction between raw and painted material. The painting plant functionality relies on some IOT technologies such as RFID tags and readers for the identification of the transport units entering and exiting the VER50 and a 3D vision and scanning laser system, which verifies the consistency between scanned items and data declared to the system during the assembly process. The VER50 project is currently undergoing the start-up phase, which has led to further analyses, discussion of criticality and resolution of issues, such as design modifications of some transport units due to painting problems and the high number of different components, which requires teaching the robot for as many dedicated painting programs. The VER50 project will be finalized when all workstations are digitalized and the painting plant functionality is fully validated.