(57) A web-forming machine having first and second endless web-forming bands (12, 14)
to receive stock in dewatering web-forming relationship therebetween, a source (18)
for depositing stock on at least one said band (12), a first web-forming roll (22)
located within the loop of the first band (12 or 14), the first and second bands (12,
14) passing over an arcuate portion of substantially 30° to 60° of the first web-forming
roll (22) in convergent wrapping relationship therewith, there being a second web-forming
roll (24) which is adjacent the first web-forming roll (22) and is located within
the loop of the second band (14 or 12) so that the first and second bands (12, 14)
pass over the second web-forming roll (24) in reverse wrapping relationship thereabout,
and means for dewatering the stock characterized in that the first web-forming roll
(22) is an open, non-suction roll and said bands (12, 14) wrap the first web-forming
roll (22) so that the web is only partially formed in a first web-forming zone (31)
adjacent the first web-forming roll (22), there being bi-directional dewatering of
the stock at the first web-forming roll (22) to form the outer faces of the web while
leaving at least an interior portion of the web unformed, and there being reversal
of internal water flow through a portion of the thickness of the web at a further
web-forming zone (32) adjacent the second web-forming roll (24), whereby to complete
the formation of the internal unformed portion of the web.
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