RFID Identification of the Metal Forms for Track Sleepers
InSystems Automation implemented for a track sleepers manufacturer the sleepers forms and the wagons for rail transports with RFID (Radio Frequency Identification) and integrated a MES (Manufacturing Execution System) for data collection in the production and in the manufacturing of track sleepers, in order to optimize the processes.
The automatic identification via RFID allows a real-time backtracking of the forms and wagons in the production cycle. Thanks to the data storage, every produced sleeper gehts a CV with correlated values, temperatures and hardening time. These data are correlated with the measured data in the 3D measuring plant, in order to interact in the production control and to improve the manufacturing process. With the statistical process control (SPC) of the measurement data, different sleepers can be recognized and the damages as well as the wear and tear can be automatically identified and the forms get taken out before faulty sleepers are produced. This increases the added value of the whole production process.
Process and System Description
The sleepers production process consists of several steps. The metal forms are cooled, cleaned, equipped with prestressed steel and filled with concrete. Up to seven cooled metal forms are stacked on a wagon, which transports them through a tunnel, where the sleepers harden. In the tunnel there are sensors, which record the temperatures during this process. So the operators can determine, in which stage of the hardening process they are, when it terminates and if it should be extended. After the hardening process, the metal forms are taken out of the wagons and checked by a measuring plant. The empty metal forms are taken back to the cooling system, so that the production process starts again. In order to track back the wagons, a RFID tag is applied. This tag contains an unique transponder number, which is associated to a sleeper track and a wagon. The RFID-tags are heat-resistent and resist to mechanical stress and to a harsh environment with a strong concrete dust pollution and frequent transport of the forms with cranes. The metal forms of the track sleepers consist of a frame. The sleeper form is fixed on this frame.
If a form is faulty, weil zum Beispiel neue Schwellentypen produziert werden sollen, wird die Form aus dem Produktionsprozess ausgeschleust und umgerüstet. Dabei muss der RFID-Tag nicht ausgetauscht werden. Die Transpondernummer des Tags wird einfach dem neuen Schwellentyp zugeordnet.
Der RFID tag is read by RF antennas, which are mounted at different process point. The transponder number is tracked by the MES software (Manufacturing Execution System) and the exact wagon position is shown on the user interface. Der RFID tag allows an idenfication in the measurement plant. The plant recognizes every type of sleeper before the measurement, because it reads the RFID tag and gives the informations to the measurement system.
Material Backtracking and Product Data Collection
The MES software guarantees, that every sleeper has an own production record. It visualizes the material flow of the forms and contains following functions for product data collection:
- Process data are provided with a time stamp (date and time)
- Measurement and storage of temperature and cooling time of the sleeper forms
- Saving, management and visualizing of the product and form data, so that the forms can be associated to the products
- Real-time backtracking of the sleeper forms
- Management of use and repair work time, recording and evaluation of dimensional deviations.
- Interaction with the production process, so that the forms can be automatically replaced
- Redirection of product informations between processing steps, so that deviating parameters and measurement algorithms are changed automatically
- Shift report, shift data and data recorded by the MES are displayed