Thickness measurement on cold strip:
Contact-free with high precision and irrespective of the alloy
New possibilities for highly dynamic thickness control
The new "VTLG" laser strip thickness measuring system is compact and robust, and thanks to its design features is the only laser strip thickness measuring device that measures the strip thickness in the mill during rolling. With this new system, the Friedrich Vollmer Feinmessgerätebau GmbH is giving new impetus to highly dynamic strip thickness measurement.
The new strip thickness gauge combines the benefits of many thickness measuring systems – but without their disadvantages: VTLG measures irrespective of the alloy and as precisely as contact gauges, but at the same time contact-free like X-ray and isotope gauges.
It is the only optical thickness gauge that is so compact and robust that it can be installed in the mill in the immediate vicinity of the roll gap. It thus opens up completely new possibilities for quick and precise thickness control and for quality assurance. With an internal scanning rate of 50 kHz, the scalable analog output provides the input signal for the high-speed thickness control within milliseconds.
VTLG measures the absolute thickness of the strip – just like the contact gauges for which Vollmer has been renowned worldwide for decades – but contact-free and from a safe distance. With a measuring accuracy of +/- 1 μm per millimetre strip thickness, it achieves the same precision as the tactile and X-ray gauges.
It offers different measuring ranges from 0.015 to 12.0 mm thickness. Thanks to its compact design and robust construction, it is suitable for installation in the mill. With an air gap of the C-frame of 125 or 285 mm, the sensors are positioned at a safe distance from the strip. The measuring depth lies between 400 and 1200 mm, depending on the gauge type.
But Vollmer has developed the VTLG not only for measurement in the mill – it is equally suitable for use on production lines, such as on the annealing line, in the finishing shop, on strip millers or in shear lines.