The rolling line automation system contains the entire equipments and centralized controls such as roll table, rolling mill, flying shears, loop etc from the rough-mill to the cooling bed steel roll table. The electrical equipment contains the high-voltage switch cabinet as well as the local compensation, single-quadrant DC machine speeder, four-quadrant DC machine speeder, frequency control speeder and all kinds of detection elements. And its core control methods contain:
Micro tension control: it could obtain accurately the real and stable elongation; calculate the rolling torque and compensation during the biting, rolling and tailing-out.
Loop control: data obtained by detections of the heat detector and scanner; it adopts the 6RA70 internal processing PID regulation algorithm to accurately control the loop height and maintain the values by regulating the upper and lower moving frameworks. The loop is stable during rolling the closed loop so as to guarantee the product quality.
Double-rule flying shears control: it works at the rotational speed closed-loop during the shearing process; it shears at the steady-speed section with small shearing dynamic speed-down. It works at the closed-loop of the cutting edge angle so as to return the zero-position rapidly and correctly without zero-position vibrations. The perfect detecting system could guarantee the fixed-length cutting and length measurement as well as the upper monitor communication count so as to record the production state.
Speed Cascade Control: the speed cascade could guarantee that the speed of the two rollers can be regulated by the stable elongation ratio. At the same time, in order to guarantee the effectiveness of the micro tension, the cascade speed needs to be interrupted or input in between the units.
Cooling bed steel control: the program automatically calculates the parameters of the rolling pieces such as the accelerating distance, accelerating time, braking length, braking time etc, and meanwhile it also provides interfaces for the convenience of docking with other systems.
Water-cooling Control: the water-cooling generally has three closed-loop controls: pressure closed-loop, flow closed-loop and temperature closed-loop, in which the output of the temperature closed-loop regulator is regarded s the flow input set value of the flow closed-loop regulation. It enters the flow closed-loop control when there is steel and sets the flow of the next steel according to the temperature condition of the last steel when there is no steel, at the same time, it will enter the pressure closed-loop control so as to make the backflow pressure constant at the cooling water pressure when rolling the last steel so that the flow and pressure will not change suddenly during the control switch, and not influence the cooling quality at the head of the steel.