Pre- and
Remoistening

Paper and paper fiber stocks are natural products. The WEKO fluid application systems (WFA) return the desired moisture to the paper and create optimal processing conditions.

INSPIRED BY NATURE - HUMIDITY

Paper consists mainly of natural cell and fiber materials. If they dry out, they lose many of their good features. The paper fibers shrink up to 25% in width. The paper web becomes tense and the tendency to “curl” or “wave” increases. The same happens to static charging.
Particularly in the case of paper webs coated or laminated on one side, where the coating side represents the rigid, immobile part, curl or lack of flatness occurs very quickly after the drying process due to the tensions. For example, with siliconized or aluminum coated papers.

WEKO fluid application systems return precisely defined moisture to the paper. By applying very fine micro-droplets, the paper regains its original running and dimensional features. It lies flat in its original dimension, static charges are prevented. The paper fibers become flexible again.
Optimum processing speed, fewer production interruptions and higher-quality products are the result.

Advantages at a glance:

• Precise, minimal and repeatable application quantities

• Resource-saving due to minimal consumption

• Contact-free application of the emulsion

• Wide application spectrum for all paper grades and ink coverage

• No wear and tear or job-related exchange parts

• High flexibility - single- or double-sided application possible

• Intuitive, easy operation

The WEKO-SIGMA is the application unit and sprays contactless and precise micro droplets onto the paper web.

With the WEKO-FLOW, WEKO-C trend or WEKO-BASIC supply units, the application quantity can be precisely and reproducibly controlled and automatically adjusted to the web speed. When connected to a moisture measuring system, it is possible to react automatically to different material pre-humidities.
Optionally, there is the possibility of zonal moistening, which compensates for uneven moisture profiles of a paper or fabric web.

The WEKO-C trend combines all the necessary components (electrics, hydraulics and tank) compactly in a closed cabinet.

In web offset printing, the WEKO-RFS is used; here, the original moisture is returned to the paper with the aid of a press-in roller. With maximum flexibility, the dosing can be very precise and reproducible at any time.