| 摘要 |
<p>The invention concerns a drying unit in the dryer section of a paper or board machine, in which drying unit there is a loop of a drying wire (32; 32a, 32b, 32c, 32d). The drying unit comprises a large-diameter D1 impingement-drying and/or through-drying cylinder (31), which is fitted inside the drying-wire loop (32, 32a, 32b, 32c, 32d). On top of said cylinder (31) and/or in the vicinity of said cylinder, at both sides, smooth-faced heated contact-drying cylinders (30) are placed, whose diameter D2 < D1. The impingement-drying and/or through-drying cylinder (31) is placed in the spaces (KT) underneath the floor level (K1-K1) of the paper machine hall and provided with an openable and closable blow hood (35) so that the removal of broke out of connection with the hood (35) takes place substantially by the force of gravity. The central axes of the contact-drying cylinders (30) placed in the vicinity of said cylinder (31) are placed in the vicinity of, or above, the floor level (K1-K1) of the paper machine hall. The curve sector b of the paper web (W) on the outer face of the drying wire (32; 32a, 32b, 32c, 32d) over said cylinder (31) is b > 180°.</p> |
