Slitting machine is to strip into a number of required specifications strip base by the steel and steel welded together, qualitative treatment.
1. Constant tension control principle
For the constant tension control during the unwinding and unwinding process, it is necessary to know the change of the coil diameter during the running. Due to the change of the winding diameter, in order to keep the load running, the split machine needs the output torque of the motor to follow the change of the winding diameter . For the V series inverter, because it can do the torque control, so to complete winding constant tension control. V series inverter provides three analog input ports, AUI, AVI, ACI. This three-channel analog input can be defined as a variety of functions, so you can choose one as a torque reference, the other way as a speed limit. 0 ~ 10v corresponds to the inverter output 0 ~ motor rated torque, so by adjusting the voltage of 0 ~ 10v can complete the constant tension control. The Du Yu slitting machine, calculate the diameter of the coil is part of the tension controller to calculate, of course, to achieve with the PLC architecture is also no problem. In other words, you can set the tension in the human machine or text, through the PLC volume diameter calculation, T = F * D / 2, it can calculate the required torque output motor size, through the analog output connected to the V series frequency The torque given to the end of the device on it.
2. Synchronous speed calculation
As we know that the inverter works at low frequencies, the sub-machine AC induction motor characteristics of the poor, the activation torque is low and sub-linear, so in the whole winding process to avoid winding motor work in 2HZ the following. So the winding motor has a minimum speed limit. For a four-stage motor its synchronous speed is calculated as follows: n1 = 30f1 / p = n1 = 1500r / min = 2HZ / 50HZ = N / 1500 = N = 60rpm / min
(F1 is the nominal frequency, p is the pole number, n1 is the synchronous speed)
3. Limited speed operation
When the maximum winding diameter is reached, the minimum speed for the entire winding operation can be determined:
V =? * D * n / i = Vmin = 3.14 * 1.2 * 60/9 = 25.12 m / min
Tension control, the sub-machine to limit the speed, otherwise there will be speed, so the speed limit to run.
4. Tension and torque calculation
If F * D / 2 = T / i (F - tension, D - diameter, T - torque, i - reduction ratio), = F = 2 * T * i / D 3.7KW AC Motor, the rated torque is calculated as follows: T = 9550 * P / n = T = 24.88Nm so Fmax = 2 * 24.88 * 9 / 0.6 = 74.64N (T - rated motor torque, P - motor Rated power, n == rated motor speed)