3 thoughts on “Jet/wire ratio calculation”

  1. cho hỏi thêm công thức này đả tính đến hệ số ma sát của huyền phù bột và môi phun chưa vậy

    • Hi Lang tu buon,
      Thank for your advise.
      This is a simple and quick calculation. It did not mention the friction coefficient of a material.
      Formula: ‘265.7*sqrt(Head)/wirespeed’

  2. The relationships between basis weight, consistency, paper machine width and speed, and production rates are easily derived. It is assumed that the speed of the stock exiting the headbox is approximately equal to the speed of the machine wire. The volumetric flow rate may be expressed as a function of the three primary paper machine dimensions or in terms of the dry fiber rate and pulp consistency at the headbox.
    (21.7)Volumetric flow rate = PM speed × PM width × slice height
    (21.8)Mass flow rate = (dry fiber rate)/(consistency)
    In Eq. (21.8), one must report the consistency in units of mass per volume (such as kg/m3) to obtain the volumetric flow rate in units of volume. Often the consistency is reported as a mass % such as 0.4% (implying 0.4 kg dry pulp per 100 kg pulp slurry). If one is not careful, errors in calculations will occur because 10 kg/m3 is 1% consistency! The dry fiber rate is easily given in terms of basis weight and machine production in area (Eq. 21.9). Eq. (21.10) shows the relationship between slice height and consistency.
    (21.9)Dry fiber rate = basis weight × PM speed × PM width
    (21.10)Basis weight = slice height × consistency
    As with any equation, when solving these equations, one must be careful to insure that consistent units are used throughout the solution. In Eq. (21.10) the slice height is conveniently expressed in meters and the consistency in kg/m3. The basis weight is solved in terms of kg/m2, which is easily converted to g/m2.


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