摘要:
A method for making delivery gauge corrections at low mill speeds during threading and tailing out of a workpiece by varying the interstand tension of the workpiece. The tension between the last two stands is used with a desired tension and the delivery AGC by tension mode of an existing delivery automatic gauge control (AGC) to change the speed of the downstream stands. During the threading and tailing out phases, the delivery AGC by speed is turned off and set to zero. In the full run phase, the interstand regulators are changed to a tension by roll gap mode, and an existing delivery automatic gauge control (AGC) by speed is used to provide a stand speed reference for the downstream stands. In the full run phase, the delivery (AGC) by tension is turned off an set to zero. In the tailing out phase optionally, the tension between each stand is used in a similar manner to provide a speed reference change for each stand immediately downstream from where a tension controller is located.
摘要:
A method and apparatus are provided for the rolling of bars, rods or wire to avoid thickened ends in which a number of rolling stands are provided in tandem forming a rolling line and in which one or more of the last rolling stands in the line have separate drive means with means to regulate the speed independent of the other rolling stands to provide momentarily increased speed and tension on the two ends of the material being rolled.
摘要:
There is disclosed a method of controlling inter-stand tension in rolling mills in which a tension measuring device is provided on each stand. The tension measuring device comprises a pair of load sensing devices provided respectively at the entry and delivery sides of the roll stand. Difference between outputs from the pair of load sensing devices is used as an output value of the tension measuring device. First, while a workpiece is captured by the second stand but is not yet captured by the third stand and when the tension in the workpiece between the first and second stands is consistent with a desired value, the output value from the tension measuring device of the second stand is stored. After the workpiece has been captured by the third stand, the difference between the stored output value and the output value from the tension measuring device of the second stand is used as the measured value of tension. The tension control for the workpiece between the second and third stands is carried out on the basis of the difference between the measured value and a desired value of tension between the second and third stands.
摘要:
There are provided operation apparatus and presetting apparatus for presetting a rolling program into the operation apparatus. In response to the preset value the operation apparatus computes the forward tension stress coefficient .gamma. and the rearward tension stress coefficient .delta. in accordance with the following equation.gamma. = .delta. = (A.multidot.V/.omega.) .multidot. Kwhere .omega. represents the angular speed of the roll, K a unit conversion constant, and A.multidot.V mass flow.
摘要:
In a tandem rolling mill consisting of at least a first rolling stand and a second rolling stand, the interstand tension is controlled by the steps of detecting the rolling force P.sub.10 and rolling torque G.sub.10 at the first rolling stand after a workpiece is fed into the nip between the rolls of the first rolling stand but before the workpiece is fed into the nip between the rolls of the second rolling stand, storing in a memory the ratio G.sub.10 /P.sub.10 representative of the reference torque arm value for the first rolling stand in a tension-free state, detecting the rolling forces P.sub.1B, P.sub.2B and rolling torques G.sub.1B, G.sub.2B at the respective rolling stands immediately after the workpiece is fed into the nip between the rolls of the second rolling stand, computing the reference torque arm value G.sub.20 /P.sub.20 for the second rolling stand in a tension-free state on the basis of these detected values, and controlling the rolling speed of the first or second rolling stand so that (G.sub.10 /P.sub.10) - (G.sub.1 /P.sub.1) representing the deviation of the torque arm value detected at the first rolling stand in rolling operation from the reference torque arm value G.sub.10 /P.sub.10 stored in the memory is equal to (G.sub.20 /P.sub.20) - (G.sub.2 /P.sub.2) representing the deviation of the torque arm value detected at the second rolling stand in rolling operation from the reference torque arm value G.sub.20 /P.sub.20, whereby the workpiece can be rolled tension-free.
摘要:
A control system for the length of workpiece between stands in a multi-stand rolling mill combines a thickness signal, a width signal and a speed signal for each stand to provide a signal representing the rate of material volume going through the stand. This signal is then compared with the desired rate for each stand and the roll speed for that stand corrected accordingly. Adjustments are made for slippage and workpiece grow-back.