Siemens unveils new 6_Hi stand for CR

Siemens VAI Metals Technologies has announced an addition to its cold rolling mill range.

Compared to conventional four-high stands, the new Siroll Alusix six-high roll stand has a wider range of control on strip flatness. It is designed to allow flexible rolling scheduling and so increase productivity, especially in cases where there are frequent changes in widths or products.

Offsetting and bending of both the work rolls and intermediate rolls provides additional control options. In conjunction with the automatic flatness control system from Siemens VAI, this helps to improve the flatness of the rolled material. In the case of Siroll Alusix, roll grinding is simplified as all rolls are ground parallel.

It is therefore not necessary to prepare and store rolls with different crowns and re-grinding is made considerably easier.

The roll stand is equipped with long-stroke cylinders for setting the intermediate rolls. As a result, the position of the intermediate rolls can be adapted to the width of the material to be rolled.

The work rolls and intermediate rolls feature positive and negative roll bending, which is carried out by means of separate cylinders. This ensures a flowing transition between positive and negative bending and avoids the need to make sudden changes for compensation.

The hydraulic roll gap control function and an automatic flatness control system provide for optimum interaction of roll bending and offsetting. Compared to four-high roll stands, Siroll Alusix has a significantly wider control range providing improved strip shape correction.

The Siroll ISV (Integrated Solenoid Valve) spraying system is used for precise zone cooling and optimum lubrication of the rollers. Edge cooling is carried out with the help of the Siroll hot edge spraying system.

Siroll Alusix also dispenses with the need for flexible hydraulic connections to the work roll chocks. This facilitates fast and efficient roll change and avoids leaks at the connecting points.

Siemens VAI is adding Siroll Alusix to its portfolio for the operators of aluminium cold rolling mills. The portfolio already includes four-high stands with optional standard back-up rolls including the dynamic shaperoll (DSR) back-up roll in which the roll crown can be altered by means of internal pressure pads.