摘要 |
A headbox apparatus is disclosed for ejecting stock onto a forming wire for forming a web. The apparatus includes a housing which is connected to a pressurized source of the stock. The housing defines a tapered inlet for the flow therethrough of the stock. The tube bank has an upstream and a downstream end with the upstream end being connected to the tapered inlet such that the stock flows at a substantially constant flow rate through the inlet and through the upstream end of the tube bank to the downstream end of the tube bank. The tube bank includes a plurality of tubes for the flow therethrough of the stock. A member defines a slice chamber which has an upstream and a downstream extremity. The upstream extremity is connected to the downstream end of the tube bank, and the downstream extremity is disposed adjacent to the forming wire. The arrangement is such that the stock flows through the downstream end of the tube bank and through the upstream extremity of the slice chamber so that the stock is ejected from the downstream extremity of the slice chamber onto the forming wire. A plurality of supply conduits are connected to the upstream end of the tube back with each supply conduit being connected to a stock diluting source for permitting diluton of the stock flowing into the tube bank. A control device cooperates with the supply conduits for controlling the dilution of the stock flowing through at least some of the tubes of the tube bank for controlling the cross-machine directional basis weight of the resultant web.
|