Sprint Electric has supplied digital DC converters for plant control in a Turkish steel plant. The high mechanical and electrical loads required DC motors and controllers in compact design, which could be easily integrated into the overall control. Retrofitting increased production output and reduced waste and downtime.
The Turkish company Kocaer Haddecilik, founded at the beginning of the 1960s, specializes in the production of steel profiles: T-profiles, square bars, flat steel and window profiles according to customer requirements. Recently, an increase in production capacity of the steel plant in Aliaga near Izmir has been planned. The contract was awarded to VIB Otomasyon, a Turkish specialist in automation and drive solutions and its system integration partner Teori Elektrik. With the help of a Scada system with Profibus and Ethernet connection via fiber-optic network, the production capacity of the steel mill could be increased while waste and downtimes were reduced. The entire plant - from the steel furnace to the metal scissors to the packaging - is now controlled by three control cabinets and one plant control room.
How to shape and cut the steel in the rolling mill and scissors is an important part of the process. Due to the high mechanical and electrical load DC motors and controllers in compact design were required, which could be easily integrated into the overall control. The decision was made for Sprint Electric's PLX series digital DC converters.
Modules integrated with application software
In the PLX DC converter, extensive modules with application software are integrated as standard. With the numerous existing macros, three important process steps can be controlled quickly and easily. A cascade control controls the tension in the steel between the rolls. That is, the operator controls the tension between any two rollers via PLC automation control without affecting the rest of the mill. This is done through a fast calculation of the reference speeds, a fast reaction of the PLX DC converters and the feedback of the 1000 encoders. The PLX is also used for closed-loop control - adjusting the motor speeds allows the DC converter to keep the voltage in the steel at zero. For precise control of the cutting device, the spindle straightening module is used in the PLX. The integrated software ensures fast acceleration, good repeatability and a precise stop position. The difference of only 5 cm between minimum and maximum product length shows that the steels can be tailored exactly to customer requirements. By improving the new mill, Kocaer Haddecilik expects a doubling of production output.
Not just metalworking
Sprint Electric's PLX series DC converters are used not only in metalworking, but also in many other industries such as pulp and paper, rubber and plastics processing, lifting, food processing, and the pharmaceutical and chemical industries. The PLX is considered a powerful, flexible and easy to program digital DC converter. The comprehensive functions of the application software enable the effortless and efficient fulfillment even of difficult tasks without complex external hardware. The PLX is part of Sprint Electric's line of two- and four-quad DC rectifiers. The functionality and compactness of this series are particularly suitable for retrofits, if more cost-effective, modern drive systems are required.