System in a drying section of a web forming machine for guiding a sieve, and further with the web guide rolls

System in a drying section of a web forming machine for guiding a wire (12) and further, the web (14) with guide rollers (16), wherein at least one of the guide rollers (16) through the web (14) supported by the wire (12) is covered in a size of less than 90 °, characterized in that at least one guide roller (16), which is defined by the web (14) in a size of less than 90 ° is covered, a grooved roll (22) , and the grooved roll in the transverse direction of the web forming machine (22) adjacent grooves (24), wherein the grooves (24) are separate vacuum zones to the area which is covered by the web (14), and with grooves provided roller (22) as such is adapted to generate a negative pressure.