Solutions for the Global Metals Industry

PAYOFF REELMOTOR POWER (KW)BRIDLE 1 ROLL 1MOTOR POWER (KW)BRIDLE 1 ROLL 2MOTOR POWER (KW)ACCUMULATORMOTOR POWER (KW)BRIDLE 2 ROLL 1MOTOR POWER (KW)BRIDLE 2 ROLL 2MOTOR POWER (KW)INERTIALOSSES (KW)+INERTIALOSSES (KW)INERTIA+ +LOSSES (KW)INERTIALOSSES (KW)+INERTIALOSSES (KW)+INERTIALOSSES (KW)+FRICTIONLOSSES (KW)FRICTION+LOSSES (KW)+FRICTIONLOSSES (KW)+FRICTIONLOSSES (KW)+FRICTIONLOSSES (KW)+FRICTIONLOSSES (KW)+ROLL 1 LOADCONSTANT (%)XROLL 1 LOADCONSTANT (%)XROLL 1 LOADCONSTANT (%)XROLL 2 LOADCONSTANT (%)XTENSIONPOWER (KW)TENSIONPOWER (KW)TENSIONPOWER (KW)TENSIONPOWER (KW)XLSCONSTXLSCONSTXLSCONSTXLSCONST–+ +–+ –+–ROLLS DOWNBRUSHES DOWNFLATTENERLOSSES (KG)PRECLEANERLOSSES (KG)0.5* TOWERLOSSES (KG)ZERO (KG)0.5 * TOWERLOSSES (KG)ZERO (KG)PAYOFFTENSION (KG)LS = LINE SPEED (METERS/MINUTE)ACCUMULATORTENSION (KG)LS = LINE SPEED (METERS/MINUTE)TANKTENSION (KG)Designing the Strip Transport Control SystemTMEIC executes three major steps in designing an effective striptransport control system:• Analyze the primary strip transport machines (reels, accumulators,and bridles) using off-line models to determine the capacitiesand limitations of each.• Develop a tension profile one-line diagram to outline therequirements for tension reference distribution, losscompensation, tension limits, and regulator configuration.• Develop a run/jog matrix showing which drive and/or drivegroups are involved in each run or jog function, the regulatorconfigurations for each mode, and the drive loading requirements.Implementing the Open Loop Feed-Forward ControlThe feed-forward network consists of on-line control algorithmsproviding:• Compensation for the inertia of the motors, gearboxes, anddirectly connected mechanical equipment.• Compensation for friction and windage losses of motors,gearboxes, and directly connected mechanical equipment.• Strip tension referencing to load the drives with the torquesdetermined from line tension setpoint data and process losscalculations.The complete system consists of closed loop regulators and openloop feed-forward elements. However, the main element is the feedforwardcontrol which minimizes the need for reactive correctionby the closed loop regulators. The result is superior strip transportperformance.ModelsOff-lineAlgorithmsOn-lineDrivesLine parametersStrip flattenersTension levelersTemper millsReduction millsSide trimmers/slittersStrip bendingCatenary tension/positionConfiguration ParametersControlTorqueBridle load distributionFriction & windage loss compensationInertia compensationStrip bending loss compensationStrip catenary/position controlSide trimmer/slitter loss compensationWeld trackingSetpoint distributionAutomation System Delivers Significant Customer BenefitsTMEIC’s advanced process line controls have been applied to metal processing lines with excellent results. Our experienceincludes controls for galvanizing lines, pickle lines, tinning lines, coating, and painting lines. Actual system operation andline performance data obtained from operating mills have demonstrated the following customer benefits:• Reduced operator intervention• Zero product quality degradation• Maximized line throughput and uptime• Maximized product capacity• Seamless product transitions© 2011 TMEIC Corporation. All Rights Reserved.Page 19 of 40