Solutions for the Global Metals Industry

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Slab Sizing Press & Roughing MillThe slab sizing press and roughing mill reduce the widthand thickness of the slab in preparation for the finishingmill. With a large width reduction, the slab sizing presstailors each slab to a particular order. The roughing millmodels provide the target width reduction to the level1 controller, which takes each slab to this desired widththrough a series of press actions. The press is electricallydriven by a large medium voltage motor and drive.Hydraulically driven top and bottom hold down rollsprevent buckling of the slab. Width gauges at the pressentry and at the roughing mill exit validate that the targetwidth is achieved. The entire process is monitored byoperators on HMI screens.Significant Improvements to Operation of the Slab Sizing Press & Roughing MillAdvanced features of the TMEIC system includeimproved caster efficiency, increased mill widthreduction capability, improved width uniformity, andimproved control tolerances. Control features includemicro-tracking (fast tracking) of slab position and speed,performed for the position and pressure regulators.The advanced sizing press model calculations include:• Die gap calculations for the anvil control• Head, body and tail draft calculations for widthreduction• Hold down roll force calculations for buckleprevention• Preforming length calculations for the taperedsections• Table lift calculations to compensate for increasingslab height• Slab elongation ratio and travel time calculationsSlab Sizing PressRoughing MillThe roughing mills (RM) reduce the width and thickness of the bar. They can bereversing, continuous, or a combination of both.Roughing Mill ScreenSlab Tracking RM ModelsControl starts with the level 2 slab tracking function, directing the level 1 sequencingand regulators based on which zone the slab is in. Hot metal detectors and othersensors are used to define the zone transitions. Specific mill references distributedfrom the tracking and set-up models include:• Horizontal roll positions, side guide positions, and RM speeds• Vertical roll positions and draft compensations for the RM edgers• Spray selection for each of the millsDynamic References for Roughing MillAfter leaving the sizing press, the slab travels through the universal roughing millstands where the width is further controlled by the edger drafting. Prior to each pass,the level 2 set-up model provides a new set of references to the mill.Reversing Mill ScreenLooperless Tension Control Between Close Coupled Tandem Roughing StandsClose coupled roughing stands further reduce the width and thickness preparing theslab for the finishing mill stands. Low tension control is applied between the closecoupled stands including coupled edgers.Page 8 of 40© 2011 TMEIC Corporation. All Rights Reserved.
Edge & Bar Induction HeatersInduction heating is a fast and efficient method of heating moving metal, and it has been applied to various metalprocessing lines. TMEIC has applied large capacity induction heaters to hot strip mills since 1984. They are used for edgeheating and bar heating to obtain uniform temperature before the bar enters the finishing mill, and have been installed onmany new hot strip mills in recent years.Three types of induction heaters are available:Solenoid TypeThis type has a flat heating characteristic, used inhot strip mills for bar heating.Transverse TypeThis type has a partial heating characteristic andhas been used for bar center heating.C-shape Transverse TypeThis type has high heating efficiency and is usedfor edge heating.Solenoid Type Bar Heater- Power level: up to 9,000 kW- Inductor frequency: 1,400 Hz- Temperature rise: 40°CC-Shape Transverse Type Edge Heater- Power level: up to 4,000 kW- Inductor frequency: 300 Hz- Temperature rise: 50°CTemperature [Deg.C]1120110010801060104010201000980960BAR TEMPERATURE CURVEBAR TEMPERATURE CURVE (Hot Bar 1730 mm - 40 mm T)0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18DistanceAverageCenter-CenterCenter-SurfaceEdge-CenterEdge SurfaceBar Heating Temperature SimulationBefore the edge heaters, thetemperature differential between thebar edge and the center is about 50º C.After the bar heaters, the temperaturedifferential has been reduced to about10º C.EDGE EDGEHEATER HEATER1EDGEHEATER2BARHEATER1BARHEATER2SIDE GUIDECROP SHEAR© 2011 TMEIC Corporation. All Rights Reserved.Page 9 of 40
Page 1 and 2: Solutions for the Global Metals Ind
Page 3 and 4: Why Our Systems Set Production Reco
Page 5 and 6: Total Solutions for Mill Automation
Page 7: Caster & Furnace ControlCaster Cont
Page 11 and 12: Coiling Temperature ControlSteel cu
Page 13 and 14: Steckel MillThe Steckel mill is a u
Page 15 and 16: Material Properties Prediction Syst
Page 17 and 18: Integrating Models for Superior Con
Page 19 and 20: PAYOFF REELMOTOR POWER (KW)BRIDLE 1
Page 21 and 22: Section MillsTMEIC has automated ma
Page 23 and 24: Early 1980’s Legacy System Archit
Page 25 and 26: Early 1990’s Legacy System Archit
Page 27 and 28: ServicesTMEIC’s Metals Engineerin
Page 29 and 30: Detailed Hardware/Software Design &
Page 31 and 32: Industry Leading Process Simulation
Page 33 and 34: Drive Training at our Training Cent
Page 35 and 36: ProductsA Family of AC & DC System
Page 37 and 38: nv Series ControllerThe Unified nv
Page 39 and 40: Mill Level 2 Software and ModelsLev

Solutions for the Global Metals Industry

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