SUCTION ROLL OF A PAPER OR BOARD MACHINE AND A METHOD IN CONNECTION WITH A SUCTION ROLL OF A PAPER OR BOARD MACHINE

摘要

The invention relates to a suction roll of a paper or board machine comprising a perforated roll shell (12) attached to end flanges at the ends of the suction roll (10), a suction box (20) being arranged inside the roll shell (12), by means of which suction box a suction effect is applied to a perforation (18) of the shell (12) of the roll (10) to a suction zone (C) defined by means of seals (15, 16), means for passing water out of connection with the roll being arranged in connection with the suction roll (10). The suction roll (10) comprises means (17) for passing replacement air between the suction box (20) and the shell (12) into an area (B) situated after the suction zone (C) in order to release negative pressure so that water is efficiently removed from the perforation (18) of the roll shell (12) in the water removal area. The invention also relates to a method in connection with a suction roll of a paper or board machine, in which method a suction roll (10) of a paper or board machine is used, the suction roll comprising a perforated roll shell (12) attached to end flanges at the ends of the suction roll (10), a suction box (20) being arranged inside the roll shell (12), by means of which suction box a suction effect is applied to a perforation (18) of the shell (12) of the roll (10) to a suction zone (C) defined by means of seals (15, 16), means for passing water out of connection with the roll being arranged in connection with the suction roll (10). The method comprises the step of passing replacement air between the suction box (20) and the shell (12) into an area (B) situated after the suction zone (C) in order to release negative pressure so that water is efficiently removed from the perforation (18) of the roll shell (12) in the water removal area.