| 摘要 |
<p>Pulping apparatus for pulping high consistency paper pulp includes a tub 10 having a bottom wall 13 and a generally cylindrical side wall 14 extending upwardly therefrom, and a rotor 20 mounted centrally of the bottom wall for rotation about a vertical axis and having a hub portion 21, a plurality of vanes 22 extending generally radially outwardly from the hub and having pumping 27 and defibering faces 26 thereon, and a plurality of helical screw flights 33 extending upwardly frown the hub. Each flight 33 has a concave undersurface 44 such that rotation of the rotor in the presence of high consistency pulp causes the screw flights to draw pulp inwardly toward the axis of rotation and push it downwardly to the defibering faces 26 of the vanes 22, and the outer surface of each flight 45 being convexly curved and of substantially greater surface are than its undersurface to provide an air foil effect further tending to draw pulp into the path of the undersurface of the following flight. The screw flights 33 preferably include trailing portions 35 having raised peripheral ridges 40 extending upwardly therefrom to prevent stock from flowing outwardly from the rotor until it reaches the vicinity of the vanes. The trailing portions 35 of the screw flights 33 preferably have a width, measured in a radial direction, which is substantially the same as the length of the vanes 22 such that pulp can be pushed downwardly and outwardly into the entire path of the working faces 26-27 of the vanes.</p> |
