| 摘要 |
To defiber a wide variety of materials, rotor and stator constructions are varied 1) to increase the agitation of stock in a tank or 2) to increase defibering effectiveness and increase flow rate through a recirculation line or to downstream equipment. To increase agitation, lobes of the stator are configured and sized to reduce the stator-rotor interface below 50% of its maximum possible value. To increase defibering effectiveness and increase the recirculation flow rate, the stator lobes are configured and sized so the stator area at the interface exceeds 50% of its maximum possible value. These lobe area changes are made in a way that also preserves a desired acquisition angle on cutting edges on rotor for the given material so that the lobes reliably "acquire" and reduce the stock. To increase homogeneity of treatment, deflectors on the stator and/or rotor require that all the stock traverses the defibering interface between peripheral teeth on the rotor and opposed stator bars. To increase the operational life of the rotor-stator pair, the rotor has an axially-thickened, cylindrically-shaped peripheral flange and is periodically axially advanced toward the stator to compensate for wear. To extend rotor-stator life when operating on very abrasive materials, the leading edges of the rotor blades are profiled at their tips to distribute the wear more evenly. To defiber more finely or more coarsely, the number and spacing of the rotor teeth are changed. For coarse milling, at least the tooth before each of a set of equiangularly spaced rotor blades is omitted.
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