Dynaflo-TW is a 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.
The excellent stock dispersion is guaranteed by the exclusive Dynaflo tubes, the turbulence generating device at the basis of this modern hydraulic headbox.
The flow coming from the computer designed tapered header passes through a first perforated plate into a mixing/equalizing chamber that optimizes the stock pressure and fiber suspension just before the turbulence generator, which is the core of the DYNAFLO concept. The stainless steel Dynaflo tubes present a conical cross section, transitioning gradually from round to rectangular. After a high acceleration at the inlet orifice, a gradual diffusion of the stock flow along the Dynaflo tubes weakens the large-scale turbulence, while sustaining small-scale turbulence, thanks to the many boundary layers generated by the friction with the tube walls.
Each tubes row has an optimum velocity range: by multiplying the tubes row, a great range of flow rates can be accommodated, giving this headbox design the greatest adaptability to all operating conditions. The configuration of the tubes row ensures a negligible residual wake signature on the stock jet.
Our team is ready to assist you from the design phase to the complete turn-key service. Ask more information.
DYNAFLO-TWL
Like for the model DYNAFLO-FL, also in the DYNAFLO-TWL the headbox can be supplied with lamellas, which maintain high the level of micro-turbulence up to the jet exit improving paper formation at high speed.
The special lamellas' tip design is performed to avoid wake effect in of the slice flow.
The DYNAFLO-TWL is available also in a multilayer layout, which makes possible the use of two or three different stock characteristics and quality to produce multilayer paper with one forming section. 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 of the headbox, from 60% up to 160% of the nominal flow, thus permitting optimal fibre distribution on the entire paper width. The Dynaflo construction, 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 CD profiling is performed by a dilution profiling control through QCS. A manual CD profiling by micro-screw jacks spaced 150 mm is also supplied. The different available sizes of the Dynaflo-TWL cover a range from 3 to 20 mᶟ/m.
Our team is ready to assist you from the design phase to the complete turn-key service. Ask more information.
