| 摘要 |
1,045,361. Sheet casting. STOCKHOLMS SUPERFOSFAT FABRIKS A.B. Jan. 7, 1964 [Jan. 9, 1963; March 18, 1963], No. 748/64. Heading B5A. [Also in Division B2] In a sheet-casting apparatus an endless belt 1 in the form of a screen or lattice, receives a viscous plastic material, e.g. a plastisal from a hopper 4, provided with a doctor knife 5. The material passes by gravity through the openings in the belt to form projections or ribs and is gelled by the action of heaters 6 and 7 before being stripped by a roll 10 and passed to a receiving roller 9. The belt 1 passes through a bath 12 containing a release agent and is preheated by a heater 8. In a modification, the sheet is provided with a backing of fabric which is fed from a roll on to the material on the belt 1. The fabric passes below and receives paste from a second hopper. A shield in the form of an endless belt passes between the heaters and the belt so that sections of the sheet being cast gelatinize at different speeds. To the same effect, the heaters may be located at varying distances from the belt 1 or be operated periodically. |
