Doctor for a suction roll

Abstract

The invention concerns a method and a device for removing water out of the perforations in a suction roll wherein a doctor blade is brought into contact with the face of the suction roll. The doctor blade is mounted with its slat face in such an angular position in relation to the face of the suction roll that the angle between the face plane of the doctor blade and the tangential direction of the face of the suction roll, when the tangent is drawn at the contact point between the tip of the doctor blade and the face of the suction roll, is from about 2.degree. to about 10.degree.. In the method, water is removed by means of the inlet-side surface plane of the doctor blade, the inlet side being seen in the sense of rotation of the suction roll, and the water is allowed to flow smoothly over the doctor blade out of contact with the construction. According to the invention, water may be additionally removed by means of a suction effect out of the area between the slat face of the doctor blade and the suction roll, negative pressure being produced in the space. The negative pressure produces flow of water out of the perforations or grooves in the suction roll.

Dependencies are inferred from the claim text.