Abstract: A conveyor-collator assembly for use in forming stacks of articles, e.g. concrete roof tiles (T) at speeds of up to 200 tiles per minute, is provided with a conveyor means (42) by which tiles (T) are fed seriatim to a velocity control means (72) whereby each tile (T) is transferred under "no-load" or substantially "no-load" conditions onto a falling shelf conveyor (140). Tiles (T) held in the conveyor (140) are thereafter deposited onto a support (26-28) of a stack forming means (24) under "no-load" or substantially "no-load" conditions whereby breakages of tiles (T) due to "shock loads" experienced hitherto in prior art arrangements is eliminated.

Abstract: The invention relates to a silicate compound having at least one alkaline oxide and silicon dioxide-containing amorphous binder matrix and also containing oxides from the aluminum, calcium, titanium, magnesium, zirconium, and/or boric oxide group. To provide a silicate compound which is suitable for both making a moulding and coating a substrate, resistant to effects like weathering, especially through alternate frost and thaw, and attack by acids, lyes or fouling, it is proposed that the amorphous binder matrix contain 4 to 25 mol silicon dioxide per mol alkaline oxide, the alkaline oxide being lithium, sodium, and/or potassium oxide and the amorphous binder matrix also contains up to 80 mol aluminum oxide and/or up to 45 mol calcium, titanium, magnesium, zirconium, and/or boric oxide evenly distributed per 100 mol silicon dioxide.

Abstract: A roof tile making machine and its method of operation. The reinforcement ribs on the underside of a concrete roofing tile are formed during their manufacture by directing mortar into recesses in a pallet on which the tile is made, with a compactor means in the form of multi-tined wheels compacting the mortar in the recesses, and providing thereafter a secondary layer of mortar over the compacted reinforcement ribs, to complete the tile in a conventional manner. A tile provided by the apparatus of the invention has reinforcement ribs which are compacted to the same degree as the remainder of the tile, thereby ensuring that the finished product, when cured, has a uniform, or substantially uniform, strength.