Paper and paperboard machine

Headbox

After being deaerated, diluted and screened in the approach system, the suspension consisting of fibres, additives and water is pumped into the headbox of the paper machine. With hydraulic headboxes, the material reaches the sieve via a tapered cross-flow distributor as well as several pipe manifolds leading to the slice outlet. The exit speed from the slice is adjusted to the speed of the wire mesh conveyor via the headbox pump pressure. The area around the headbox is extremely damp and warm.

Pressure measurement with VEGABAR 52

A pressure measurement in the hydraulic headbox is used for direct speed control of the stock feed pump. It must be very precise and is thus implemented redundantly. The measuring points are located near the slice on the tender side and drive side of the machine. The optimal solution is VEGABAR 52 in absolutely front-flush version, with accuracy class 0.05 and high protection rating IP 68. In headboxes with superimposed air cushion, stock flow is often regulated via the level. The ideal solution here is the radar sensor VEGAPULS 63. It can be installed front-flush from above, has an encapsulated antenna system and measures with millimetre precision.