Filtration structure for the pad of a press for producing single-layer cement tiles with filtration surfaces and apparatus for replacing such filtration surfaces

摘要

In an end board (32) that can be attached to and detached from the pad, the active surface (32A) for the molding action comprises multiple narrow grooves (42, 44) for extraction of the liquid phase, and a peripheral passageway (46); a filtration layer (40B) laid on said active surface (32A) - with optional interposition of a filter backing (40A) - has peripheral lips projecting over said peripheral passageway (46); and clamping bars (50) are forcibly inserted into said peripheral passageway (46) to trap the said peripheral lips (40C) of the filter (40B) in said channel, thereby tensioning it; which bars are expelled through holes (54).