The fluid dynamics are optimized in all headbox sections – tapered header, step diffusor turbulence generator, nozzle with lamellas, and slice area – to ensure a uniform and stable jet. This produces a homogeneous distribution of all raw materials within the final sheet. The compact design minimizes slice deflection even at high pressures. In combination with PrimeProFiler F dilution profiling system, the most uniform basis weight profiles are achieved. The papermaker’s requirements for operating safety and easy access for cleaning have been taken into account. Electro-polished surfaces ensure excellent cleanliness and high availability.
The PrimeFlow AT (accelerating tube) headbox reflects to successful combination of ANDRITZ and Paperchine‘s history and experience in papermaking. The patented accelerating tube headbox with unique nested trapezoid outlets features a rugged design structure, sheets in the nozzle for turbulence control, and capacity for high resolution dilution profiling. This provides excellent jet quality, fiber dispersion and fiber orientation control over a wide grade and speed range. This results in excellent 2 sigma results over a wide operating range. The headbox also includes flexible lamella and is available with or without the indirect consistency profiling injection. The PrimeFlow AT headbox is available for new machines, conversions, and rebuilds, for all kinds of paper and board machines.
The new soft-layering concept of the PrimeFlow AT headbox enables selective layer enhancement by feeding in various additives through the dilution control system. This simple system, where one of the rows is connected to an alternative supply system, results in low investment costs with high sheet formation quality. The soft-layering concept can also be added to existing PrimeFlow headboxes that are already in operation.
