CA2168119A1 - Gap former in a paper machine - Google Patents

Abstract

The invention concerns a gap former in a paper machine, comprising a twin-wire zone, which is composed of a first forming-wire loop (10) and of a second forming-wire loop (20) and which starts from the forming gap (G), into which the slice part (31) of the headbox (30) feeds a pulp suspension jet. The forming gap (G) is defined, from one side, by the first forming wire (10), which runs over the forming roll (11), and, from the opposite side, by the substantially straight run of the second forming wire (20) starting from the breast roll (21) to the forming roll (11). Draining equipment (40...44) is fitted inside the first forming-wire loop (10) after the forming gap (G) and the forming roll (11), which draining equipment is provided with a deflector duct (12) and with a deflector rib (12a) placed against the first forming wire (10) in the lower part of said deflector duct (12), and, inside the second wire loop (20), a forming shoe is arranged, which is provided with a ribbed deck consisting of forming ribs (22) and which is loaded against the second forming wire (20). In the invention, the first forming rib of the forming shoe or a unified forming-rib construction (22) composed of two or more forming ribs is mounted so that it can be loaded adjustably, so that the free run of the forming wires (10, 20) from the forming roll (11) to the first forming rib is substantially little.