| 摘要 |
1283053 Centrifugal strainer P C WILSON and R P HUGHART 4 Aug 1969 [12 Aug 1968] 4057/72 Divided out of 1283052 Heading B1D A centrifugal strainer for cellulose pulp comprises a rotating perforate screen 22 along which pulp is moved by an internal, differentially rotating scroll 24 carrying helical flights, the screen holes being circular, between 0.3 and 3mm wide and forming at least 10% of the screen area, and the longitudinal axes of the flights being inclined at not more than 65 degrees to the transverse plane of the strainer. The flights may be made of or covered with elastomeric materials (exemplified) (Figs. 6 to 9, not shown) and extra flights may be provided at the inlet end of the screen. The spacing of flights from the screen and from other flights is exemplified. The scroll has apertures 178 through which wash liquid or drying gas may be fed to the pulp, the gas being withdrawn by a vacuum pump connected to the housing at 48. Screen 22 is supported by wire mesh and an outer basket (Fig. 2, not shown). The rotating screen is surrounded by a fixed screen 23 with smaller apertures, which may be woven wire or cloth or have outwardly diverging conical apertures. The inner and outer screens are shown as cylindrical, but frusto-conical and compound forms are illustrated. The elastomeric covering on the scroll flights is replaceable when worn and may be ground to match the frusto-conical rotary screen by axially adjusting the scroll until the flights engage the screen and then rotating the scroll and screen differentially. |
