Overmade DynaFlow headbox to Pratt Paper
Overmade SrL, Verona, Italy, recently delivered a DynaFlow FL hydraulic headbox to Pratt Paper (USA).
With a pond width of 6.2 m and an operational output of about 750 tpd, the headbox is intended for the bottom layer of a machine producing up to 1200 tpd of high-quality testliner and fluting at 1100 m/min. The modification is to improve the efficiency of the forming section when basis weights ranging from 100 gsm to 273 gsm are produced using up to 80% mixed waste paper and 20% OCC.
A dilution system controls the CD basis weight profile. The headbox features an additional edge flow control system, capable of locally adjusting the flow from 60% to 160% of its nominal value, designed to optimize the fiber orientation across the paper width.
The headbox has stiff lamellas in the slice area to maintain a high level of micro-turbulence up to the jet exit thus improving paper formation at high speeds.
DynaFlow-FL multi-layer headboxes are also available to permit the use of stocks of different characteristics or qualities to produce multilayer paper with a single forming section.