| 摘要 |
The extrusion of a green body from a paste or suspension of particulate solids in a liquid is conducted by a process which includes the steps of introducing flowable paste or suspension into an inlet end of a moulding passage which is defined by walls having at least one partially liquid-permeable wall section; applying pressure to the paste or suspension, thereby to remove from the passage at least a major portion of the liquid of the paste or suspension, by establishing a pressure differential across the liquid permeable section, so as to form in the passage a non-flowable body of consolidated particulate solids of the paste or suspension, and to extrude the non-flowable body progressively from an outlet end of the passage. The magnitude of the pressure, the rate of removal of liquid and the rate of extrusion are controlled to maintain the non-flowable body at a length which extends back from the outlet end of the passage and across and beyond the liquid-permeable wall section to provide a portion of the body upstream of the liquid-permeable wall section. Liquid is removed from the passage by constant pressure filtration in which liquid being forced from the suspension is filtered through the portion of the non-flowable body maintained upstream of the liquid permeable section.
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