| 摘要 |
1,152,870. Screw conveyer. ALGEMENE KUNSTZIJDE UNIE N.V. 3 Aug., 1966 [4 Aug., 1965], No. 34838/66. Heading B8A. [Also in Division F1] A screw pump for conveying a highly viscous foaming liquid such as molten polyethylene terephthalate from a vacuum reactor 1 to an outlet 4 comprises a casing having an upper conical part 2 and a lower cylindrical part 3. The impeller has an initial section a extending into the reactor 1, a second section b fitting within the conical part 2 and third and fourth sections c, d fitting within the cylindrical part 3. In terms of the constant outer diameter D over sections c, d, the outer diameter of the screw 6 may increase from about 0À4D to between 2D and 3D over section a and decrease to D over section b. The diameter of the root 5 may increase over section c from the constant value 0À2D obtaining over sections a, b to the constant value 0À9D obtaining over section d. The length of section a may be between 0À5D and D, and the length of each of sections b, c may be between 2D and 3D. The screw has a constant pitch of between 0À8D and 1À2D. Instead, the outer diameter may increase over section a from 24 mm. to 60 mm. and decrease over section b to 30 mm; the two root diameters may be 12 mm. and 24 mm.; sections a, b, c and d may respectively be 20, 50, 45 and 115 mm. long; and the pitch may be 30 mm. |
