Paper and Board

Equipment for carrying heavy, wide paper and board rolls safely, unwinding them under control and adapting one shaft to different core diameters.

Paper and board usually reach converting lines as wide, heavy rolls. In slitting and rewinding, coating, laminating, printing and sheeting, these rolls are unwound, processed, and then either rewound or cut into sheets. Paper stretches very little yet is sensitive to tearing and creasing, so choosing the right equipment to carry and brake the roll affects both throughput and waste.

Roll handling on paper lines

At the unwind, a heavy roll is paid out with a brake torque that has to change as the diameter falls. Too much tension and the paper can break; too little and the web goes slack, creases and starts to flutter. On wide rolls, the shaft’s own weight and deflection also need to be taken into account: a long shaft that bows in the middle can spoil winding quality and edge alignment. Paper dust and frequent roll changes add to the maintenance load on mechanical parts.

Which equipment goes where?

Air shaft: For heavy rolls, a steel air shaft offers the strength required. On wide machines where shaft weight needs to come down, a carbon fibre air shaft is an option to consider.
Safety chuck: Transfers the roll weight to the machine frame and transmits torque. Depending on the frame design, an inside-frame or frame-mounted type is selected.
Brake: At the unwind, a pneumatic brake or caliper brake provides unwinding resistance that can be adjusted by air pressure. Brake selection should take the required torque and heat dissipation into account together.
Adapter: When one shaft has to run cores with different inside diameters, a mechanical aluminium adapter matches the shaft to the core.
Tension and web guiding: A tension controller and a web guide controller reduce the risk of web breaks and lateral drift.

What to consider when selecting

Roll weight and width are the first criteria for choosing the shaft body material and the load capacity of the safety chuck.
On long shafts, deflection and balance should be assessed together.
Board cores can be damaged on the inside depending on how the lugs grip, so the gripping method must suit the core.
When choosing a brake, consider the heat generated in continuous running, not only peak torque.
In dusty conditions, regular checks of the air bladder, valve and lugs should be part of the maintenance plan.

For technical values see the technical dimensions page, or request a quote for your application through our contact page.