A MULTI-PLY WEB FORMING APPARATUS

摘要

A multi-ply web forming apparatus is disclosed for forming a top ply on a base ply. The former includes a looped lower forming wire (16) for receiving the base ply thereon and a top looped forming wire (18) cooperating with and disposed above the lower wire for defining therebetween a generally horizontally disposed forming section (20) having a first (22) and a second end (24). A turning bar (26) defines a curved surface (28) for guiding the lower wire. A secondary headbox (30) ejects stock towards and onto the base ply. A curved dewatering shoe (34) is disposed beneath the lower wire (16) such that a portion of water from the top ply is ejected through the top wire (18). A vacuum slot (38) collects a portion of water upwardly away from the top wire. An inverted vacuum box (40) is disposed downstream relative to the vacuum slot (38) and a plurality of dewatering blades (44-56) disposed between a curved face (42) of the vacuum box and the top wire (18) guide the top wire therepast. A plurality of dewatering foils (58-61) are disposed on the opposite side of the wire relative to the blades such that the consistency of the stock forming the top ply is increased during passage thereof through the forming section while maintaining the consistency of the top ply uniform in a "Z" direction so that crushing of the resultant web is inhibited.