Detection of strip position is the absolute crucial element for all strip guiding solutions. Traditionally this task is performed either with optical, capacitive or inductive sensors. EMG has a track record for stable sensor solutions also for furnaces and high temperatures up to 1100 °C.
The latest generation of EMG’s technology portfolio for furnace solutions is based on the so called Vivaldi antenna technology. Vivaldi antennas are co-planar antennas with Ultra-Wide-Band characteristics. With EMG-Vivaldi® the current limitations of radar, capacitive or inductive sensor solutions for furnaces could be overcome. The EMG-Vivaldi® sensor is located outside the furnace atmosphere and measures through the furnace wall in a certain wavelength region of the radar spectrum. It focuses on the edge of thin metal strips (> 0.1 mm) through a non-conductive / non-metal and gas-tight isolation of the furnace wall. Therefore costly cooling of sensors inside the furnace is not necessary. The furnace wall is completely closed and the strip can never hit or damage the sensor itself. Another important feature is the easy calibration based on simple reference measurements. The system is maintenance-free and promises therefore very low costs of ownership.
The results of one of the first installations at California Steel, USA, show the EMG-Vivaldi® technique can also replace older systems, in a riskless and comparatively easy manner: “The installation was easy and accomplished on schedule. System set-up was coordinated well by EMG personnel and the steering control was excellent from the very beginning” and further: “The system has been operating very well since the installation (in 2013) without any issues” (John Wray, Senior Engineer at California Steel Industries).
In summary: EMG-Vivaldi® represents the newest generation of EMG strip guiding sensors for application in harsh environments, like high temperature annealing furnaces. It utilizes Ultra- Wide-Band radar technology for a sensor solution enabling the strip edge detection through gas-tight furnace walls. By that it realizes a long-held dream of strip position measurement in continuous annealing furnaces without interfering the furnace atmosphere or the furnace geometry. In the meantime various industrial projects e.g. at California Steel, ThyssenKrupp Steel, ArcelorMittal and others proofed the industrial robustness and accuracy of EMG-Vivaldi®.
Do you want to know more about EMG-Vivaldi®? If so, you are heartily invited to visit the the ESTAD conference in Düsseldorf which takes place parallel to the METEC trade fair to observe our presentation about "EMG-Vivaldi®: Industrial proof of the new paradigm for strip guiding in furnace atmospheres". This presentation will be given on June 17th at 11:40.