Decoilers

Managing the decoiling speed control

The metal forming process involves the so-called decoilers. Such machines are used to feed transversal or longitudinal cutting plants.

The material to be decoiled can be: cold or hot rolled steel, coated steel, silicon steel, stainless steel or aluminium.

The hydraulic driving system is dimensioned in order to handle coils weighing up to 20 tons with a metal thickness from 0.3 to 4 mm. The system can also manage the decoiling speed control of the strip up to 200 meters per minute with an average width of 1000 mm.

The hydraulic system supplied by Duplomatic Oleodinamica consists of two power units: the former is used for the line which enables the spindle expansion and the decoiler transversal alignment, the latter is dedicated to the circuit for the decoiler breaking.

The aim of the application is to ensure the “pull back” with a constant opposite strength through the breaking of the hydraulic motor via two pilot operated pressure relief valves (one for each rotation direction); such valves are used in this specific case as counterpressure valves.

The breaking regulation occurs through a potentiometer which gives the reference signal to a proportional pressure reducing
valve.

The involved flow rates reach 200 l/min and are generated by the rotation of the hydraulic motor with a breaking pressure up to 200 bars.