Using the RDMS profile measurement system from LAP, steel industry plants can measure the contours of glowing wires, bar steel and tubes in the production process completely automatically. Software warns in real-time about imminent tolerance infringements even before the product quality suffers. Users can specifically optimise the capability of the individual structures locally and avoid costly rework. The RDMS profile measurement system can also be integrated in existing lines where space is limited. It is currently the most compact measuring system on the market.
In times of increasing competitive pressure in the steel industry, maximum production efficiency is required. For this, many manufacturers are migrating to measuring wires, steel bars and tubes not only at the end of the production process but between each production step. They can thus assign tolerance errors directly to the respective systems and adjust these optimally.
Completely automatic profile measurement using six axes
"The profile of common bar steel geometries can be measured with the RDMS profile measurement system – including rounds, squares, flats and hexagons", explains Frank Lohmann, Senior Sales Manager Steel Industry at LAP. "Stationary sensors measure over several axes during the rolling. Not only diameters of wire, bar steel and tubes - they also provide precise measured values about roll offset and breakout, eccentricity, ovality and tension and pressure influences."
Up to six METIS measuring systems can be integrated in the round measuring frame of the RDMS which the product passes through. They consist in each case of transmitter and receiver. The laser beam of a diode laser in the transmitter falls onto a rotating polygon mirror. A precision lens converts the deflected laser beam into a parallel running beam which passes through the measuring range cyclically.
The glowing steel shades the opposite receiver when it passes through the maximum 500 millimetres wide measuring field. The time interval can be converted into dimension values. Each pair of devices provides an authentic cross section profile from different viewing angles even at high rolling speeds.
Software warns in real-time about imminent tolerance infringements
The LAP software evaluates the measurements in real-time. "With comprehensive trend analyses and statistics functions, they can indicate on a monitor to the local employees in good time when tolerance infringements are approaching", says Lohmann. "They can then optimise the rolling process directly and specifically and thus reduce rework."
This pays for itself for companies, even for frequently changing products. As employees can dispense with sample cutting thanks to the RDMS profile measurement system, the start-up times for product changes can be significantly shortened.
As a standard feature, various movement modes can be selected using the software. From the stationary RDMS to the constantly swivelling RDMS SWING to a cyclically swivelling operating mode which LAP calls the RDMS MIXED MODE.
LAP provides software enhancements specially for ribbed steel and for products rolled using triple plate technology.
The results of several measurement systems can be visualised in one software application for 100% quality control. From the furnace to the cooling bed, the user can install a measurement system after each production step. This provides him with an overview of the complete production process. The user can thus detect sources of error immediately and eliminate them specifically. All measured data can be stored in the IT system, optionally in an open SQL database of LAP, whose data can then be further processed statistically. Frank Lohmann: "LAP is also planning a closed control loop for the future so that rolling lines can be automatically controlled in real-time using the measured data."
RDMS – the most compact measuring system on the market
The RDMS profile measurement system can also be integrated in existing process control systems and material tracking systems using standard interfaces and Ethernet. The measuring frame itself is also very narrow as the system does not require any complex rotating mechanism and can also be integrated in existing lines where space is limited. "The newest version of our RDMS is the most compact gauge on the market", says Lohmann. Dispensing with the rotating mechanism also makes the measuring system particularly low maintenance.
