What's the SWA principle?

Derichs-SWA-rolls are double-shell heating and cooling rolls that can be opened thanks to a patented design.

While conventional rolls can not be opened after assembling and welding, the sleeve of a SWA-roll can be removed and reassembled as often as you like due to removable, conical rings. The mechanical properties of the roller (truth of running a.s.o.) are not influenced by opening and reassembling of the sleeve.

Why use SWA-rollers?

The interior surface of each annealed roll is stressed by the temper-medium. Especially when the heat-exchange-rate as also the temperature precision by using water is reduced a lot with the increasing lifetime of the roll.

Reasons for these disadvantages are interior pollutions that are caused by very small soiled particles, rust, dirt and encrusted oil-residues.

Furthermore the attrition and destruction of the spirals by using aggressive mediums or cleaning of the roll with aggressive acid can reduce the heat-exchange-rate of the roll, too.

By removing the outer shell easily the interior body can be cleaned and repaired thoroughly. Even badly polluted or damaged rolls can be renovated by turning off the interior surfaces or assembling of new spirals.

By "reworking" a roll in the described way its quality can be restored as if it was a new delivery.