SMART Segment & DynaGap SoftReduction. Fast thickness change and optimized slab quality for top performance. Metals Technologies

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1 SMART Segment & DynaGap SoftReduction Fast thickness change and optimized slab quality for top performance Metals Technologies

2 SMART Segment & DynaGap SoftReduction Thickness on demand / optimum center quality The challenge: If you want to reach a better internal strand quality and quick and simple remote change of casting thickness you have to answer the following questions: How long do you need to change the casting thickness? Are you satisfied with the center quality of your products? Do you intend to produce sour gas steels or heavy plates? Does your caster taper dynamically adapt to changes in steel grades or casting speed? Our solution: The technological package with numerous patented solutions featuring the combination of SMART Segments with Siemens VAI s DYNACS Dynamic Cooling Model allows dynamically optimized adjustment of the roller gap and taper during transient casting conditions, and quick and simple remote changing of casting thickness between the casts. This results in improvements of internal quality, especially for pipe and plate grades. The thermal tracking model of DYNACS determines the final point of solidification, and the DynaGap model automatically adjusts the set points for the SMART Segment for an optimum roller gap. Excellent access to SMART Segments SMART Segment robust and reliable

3 Good reasons for Siemens VAI SMART Segment & DynaGap SoftReduction : Minimized center line cracking Demonstrated thickness change of one SMART Segment in 1 minute Slab thickness tolerance improved by up to 50% Dynamic adjustment of the roll-gap profile for the entire strand guide using DynaGap SoftReduction Flexibility to cast any slab thickness within the design range Increased machine availability with the use of simple and reliable on/off valves Connect & Cast package for quick start-up and reliable function

4 Dynamic control for precise adjustment Intelligent and functional design to meet all conditions DynaGap System DynaGap practice setup Actual process data and events Gap setpoints for: Tapered strand gap DynaGap SoftReduction Liquid core reduction DynaGap Fully automatic strand-taper control for improved internal strand qualilty DynaGap control concept Functional description: Siemens VAI s revolutionary SMART technology allows for the dynamic adjustment of the roll-gap profile, even during casting! SMART is ideal for producers of plate grades and for plants with frequent casting thickness changes. Siemens VAI s trend setting SMART Segment is the ideal solution for enabling rapid changes in the casting thickness, particularly for soft reduction requirements. Contrary to other systems based on the manual adjustment of the roller gap using shims, the SMART Segment features four hydraulically activated cylinders with integrated position transducers which automatically determine the dimension of the roller gap on the basis of on-line position measurements. With this elegant and simple solution, fast roller gap adjustment is assured for any slab thickness within the design range. Manual interaction at the segments is no longer required for adjusting the casting thickness, which improves convenience and safety. With the installation of the SMART strand guide system it is possible to dynamically control the roll taper of the entire strand containment. The DynaGap SoftReduction Package featuring the combination of SMART Segment and Siemens VAI s thermal tracking module allows to dynamically adjust the roll-gap profile even under transient casting conditions. The thermal tracking module determines the point of final solidification. Thus even for changing casting speeds SMART Segments automatically readjust the roller gap taper for optimum soft reduction.

5 1 6 Main design elements of the new VAI SMART Segment with DynaGap SoftReduction for slab casters: Segment inner frame 2. DynaJet nozzle 3. Segment outer frame 4. Support frame 5. Segment fastening unit 6. Adjusting cylinder for driven rollers 7. Clamping cylinder with integrated position control for DynaGap 8. Piping 9. Integrated driven rollers Design features: Minimum maintenance requirements with the use of standard manufacturer components Achievements of close tolerances without servo valves on the basis of hydraulic control with standard valves Position locking of the inner frame of the segment for high system reliability Non contact electronic stroke sensors integrated within the cylinders for high operational reliability Well proven mechatronic design of the SMART Segments, which are already in operation in around 100 strands with excellent results DynaGap SoftReduction Package based on Siemens VAI s proven DYNACS cooling model assures dynamic gap adjustment independent of casting speed and steel grades Built in reliability concept that involves DynaGap SoftReduction, segment controller and hydraulic backup mechanismus to assure unprecedented level of operational safety 5

6 Optimized casting operations Brilliant solutions for high speed casting SMART Segments precision for success Integrated rotary joints for strand guide rollers Achieved results: Thickness change time approx. 30 minute for strand guide Thickness change of one SMART Segment in 1 minute Reduction of NACE test rejections for HIC resistant steel grades Yield optimization through thickness tolerance minimization Visually no center line defects Successfully tested for thickness ranges from 120 to 300 mm, a wide range of steel grades (incl. stainless steel) and casting speeds up to 3,3 m/min DynaGap results inner quality center segregation coefficient API-X70: mm thick plate quality (microalloyed): mm thick plate quality (microalloyed) : Strand containment with SMART Segments 6

7 casting speed 1.3 m/min grade A; thickness 254 mm at steady casting conditions casting speed change from 1.3 to 0.7 m/min grade A; thickness 254 mm after 7 min transient casting conditions Dynamic gap practices Dynamic gap practices achieve the optimum thickness reduction within a predefined range near the point of final solidification. A tunable reduction profile defined over the solidification range is used to calculate the set points for the roll gap taper. Dynamic gap practices allow safe tracking of cold steel pieces that may originate e.g. from tundish exchanges as they pass through the machine. Gap practices can be defined as absolute or relative to the mold-exit thickness. So-called relative practices have the advantage of producing a smooth transition from an accurately measured mold to the first SMART Segment. casting speed change from 1.3 to 0.7 m/min grade A; thickness 254 mm after 20 min steady casting conditions again casting speed change from 0.7 to 1.3 m/min grade A; thickness 254 mm after 14 min transient casting conditions 7

8 For further information, please contact: Siemens VAI Metals Technologies GmbH & Co P.O. Box 4, Turmstr Linz, Austria Phone: +43 (0) The information provided in this brochure contains merely general descriptions or characteristics of performance which in actual case of use do not always apply as described or which may change as a result of further development of the products. An obligation to provide the respective characteristics shall only exist if expressly agreed in the terms of contract. Order No.: E10001-M3-A21-V Printed in Austria Dispo No.: K-No.: SPS VAI PA Subject to change without prior notice Siemens AG All rights reserved.