A high-end wire and cable manufacturer in Connecticut had several older Syncro wire drawing lines with continuous-resistance annealing. Some of the lines had a fixed voltage process consisting of a contactor, transformer, and manually-set voltage taps while others had variable voltage supplies. With fixed voltage, the annealing process cannot begin until the line is at running speed. The variable-voltage design lacked a control algorithm to properly control the voltage as a function of line speed to maintain a constant elongation of the wire. EDC upgraded the existing drives with state-of-the-art Vector AC drives and EDC’s AlphaNeal™ Annealer Control with its field proven square root and annealer control algorithm.
In the continuous-resistance annealing process, the secondary of the step-down transformer is connected to the wire through a rotating sheave. The voltage potential and the low resistance of the wire cause a high current to flow through the wire, heating it up. If the wire was not passing over the sheave at a high speed, it would melt. The root mean square (RMS) power level has to increase with speed. Too little power results in hard wire and too much can burn, discolor or melt the wire. EDC has mastered the control of the annealing process solving mathematical equations in real time to provide repeatability of a quality product. EDC is able to provide a constant anneal from near zero speed to full speed and back to zero at varying line speeds resulting in a predictable, flexible, and more resilient product for secondary processes and final sale to the customer.
EDC Systems specializes in the wire and cable industry. We have retrofitted and built new applications for hundreds of annealing sections of copper and aluminum wire drawing lines ranging from 15kVA to 850kVA. Our team looks at the customer’s entire process – from the drawing machine, the annealer, to the spooler. In addition to utilizing our control solution with an algorithm to vary the voltage to the sheaves as a function of line speed in order to maintain a constant anneal, we oversize the power section. The system is digital and thus can be recipe-driven and controlled from an HMI and PLC. The result is a controller that will give the customer the performance and reliability that EDC is known for in the industry.
Many wire manufacturing plants around the world have wire drawing machines dating back to the 1970s. Many machines are workhorses and have proven to be reliable with a long productive life. However, technology has come a long way and machine upgrades can incorporate design improvements that can substantially improve productivity, serviceability, and the economic life of older drawing lines. EDC has retrofitted drawing lines from industry leaders like Syncro, Niehoff, SAMP, and more. Contact us today if you would like to evaluate a retrofit plan.