HEADBOXES
OVERMADE headboxes family extends from the traditional air-padded, two-roll headbox, for applications on low-speed Fourdriniers, to the hydraulic headbox "Dynaflo" for high speed formers and Crescent formers.
Hydraulic headboxes are conceived to guarantee:
- Excellent stock dispersion through the exclusive Dynaflo device for turbulence generation
- Best sheet formation
- Negligible residual wake signature on the jet
Options:
- Edge flow control system capable to modify locally the flow from 60% to 160% of the nominal flow to optimize fiber orientation.
- Stiff lamellas in the slice area
- Multilayer layout
- Dilution system for CD profiling control
Overmade Paper & Board Headboxes:
Dynaflo-TW: hydraulic headbox for applications on twin wire formers, at speeds from 600 to 1,500 mpm, and basis weight up to 160-180 gsm and it is designed for writing & printing paper, newsprint and packaging types
DYNAFLO-F: hydraulic headbox entirely in solid stainless steel, with thorough finish and electropolishing of all the surfaces in contact with the stock, guarantees a safe and trouble-free operations for many years. The different sizes of the Dynaflo-F cover a range from 2 to 18 m3/m.
The edge flow control is another important optional for this headbox, indeed a special system is designed to modify locally the flow on the edges, from 60% up to 160% of the nominal flow, thus permitting an optimal fibre distribution on the entire paper width
Roll Set-S: two-rolls, air-padded headbox, designed for special applications (decorative papers, highly charged papers) on Fourdrinier machines with speeds from 100 to 600 mpm and basis weight up to 180 gsm. The CD profiling is realized manually or automatically, QCS driven, by micro-screw jacks spaced 150 mm, or optionally 100 mm. The different available sizes of the Roll Set-S cover a range from 1 to 8 m3/m
Roll Set-F: traditional, two-rolls air-padded headbox. Its typical application is on the Fourdrinier, at speeds from 100 to 700 mpm, basis weight from 80 to 250 gsm, and can reach, for special board, the production of 500 gsm.
Flo Set Mk II is a hydraulic headbox designed for inclined Fourdrinier with suction breast roll tissue formers, at speeds up to 1,200 mpm
Flo Set Mk III is a hydraulic headbox designed for twin wire formers, at speeds up to 1,600 mpm. All the surfaces in contact with the stock are 316 L stainless steel clad, with thorough finish and electropolishing
Overmade Tissue Headboxes:
Dynaflo-C: hydraulic headbox for tissue Crescent formers at very high speeds, up to 2,400 mpm, and basis weight from 10 to 40 gsm.
Dynaflo-C2: hydraulic headbox specially conceived for Crescent formers on two-layers tissue grades, at speeds from 1,000 to 2,500 mpm and basis weight from 10 to 40 gsm.
Dynaflo-TWC: hydraulic headbox for tissue twin wire Formers, which operates at speeds from 750 to 2,000 mpm and basis weight from 10 to 32 gsm.
An excellent stock dispersion is guaranteed by the exclusive Dynaflo tubes, the turbulence generating device at the basis of OVER's modern hydraulic headbox design.
