A perforated roll (10) of a fiber web machine includes a roll shell (19), holes (13) extending through the roll shell, and a sensing system (14) arranged in the roll shell. The sensing system (14) includes at least one pair of leads (16), to which one or more sensors (15) have been connected. At least one pair of leads is composed of flat leads (17.2, 17.2), which are arranged in the roll shell side by side. A prefabricated sensor sheet (26) may be prepared for a perforated roll of a fiber web machine, such that holes may be drilled therethrough to communicate with the roll shell holes (13).

A capillary dewatering apparatus, including a framework with a plurality of apertures, and a flexible member disposed around an exterior surface of the framework, in which an inner surface of the flexible member is in contact with at least a portion of the exterior surface of the framework and in which the flexible member and the framework are not bonded. Also disclosed is a capillary dewatering process using the corresponding apparatus.

A capillary dewatering apparatus, including a framework with a plurality of apertures, and a flexible member disposed around an exterior surface of the framework, in which an inner surface of the flexible member is in contact with at least a portion of the exterior surface of the framework and in which the flexible member and the framework are not bonded. Also disclosed is a capillary dewatering process using the corresponding apparatus.

A method for producing a fibrous pulp web, in which a fibrous pulp suspension is dewatered in a Twin Wire Former to form a fibrous pulp web which is dried with a TAD dryer. A pre-dewatering device with a hood and suction roll is provided after the Twin Wire Former and before the TAD dryer. The fibrous pulp web is guided through the pre-dewatering device between exactly two machine cloths. The machine cloth between suction roll and the web is a porous felt, and the machine cloth between web and hood is a structured wire. A volume flux of hot drying fluid greater than 100 m.sup.3/(m.sup.2.Math.min), preferably greater than 250 m.sup.3/(m.sup.2.Math.min,) is drawn through the fibrous pulp web into the suction roll.

A method for producing a fibrous pulp web, in which a fibrous pulp suspension is dewatered in a Twin Wire Former to form a fibrous pulp web which is dried with a TAD dryer. A pre-dewatering device with a hood and suction roll is provided after the Twin Wire Former and before the TAD dryer. The fibrous pulp web is guided through the pre-dewatering device between exactly two machine cloths. The machine cloth between suction roll and the web is a porous felt, and the machine cloth between web and hood is a structured wire. A volume flux of hot drying fluid greater than 100 m.sup.3/(m.sup.2.Math.min), preferably greater than 250 m.sup.3/(m.sup.2.Math.min,) is drawn through the fibrous pulp web into the suction roll.

A method for producing a fibrous pulp web, in which a fibrous pulp suspension is dewatered in a Twin Wire Former to form a fibrous pulp web which is dried with a TAD dryer. A pre-dewatering device with a hood and suction roll is provided after the Twin Wire Former and before the TAD dryer. The fibrous pulp web is guided through the pre-dewatering device between exactly two machine cloths. The machine cloth between suction roll and the web is a porous felt, and the machine cloth between web and hood is a structured wire. A volume flux of hot drying fluid greater than 100 m.sup.3/(m.sup.2min), preferably greater than 250 m.sup.3/(m.sup.2min,) is drawn through the fibrous pulp web into the suction roll.

A method for producing a fibrous pulp web, in which a fibrous pulp suspension is dewatered in a Twin Wire Former to form a fibrous pulp web which is dried with a TAD dryer. A pre-dewatering device with a hood and suction roll is provided after the Twin Wire Former and before the TAD dryer. The fibrous pulp web is guided through the pre-dewatering device between exactly two machine cloths. The machine cloth between suction roll and the web is a porous felt, and the machine cloth between web and hood is a structured wire. A volume flux of hot drying fluid greater than 100 m.sup.3/(m.sup.2min), preferably greater than 250 m.sup.3/(m.sup.2min,) is drawn through the fibrous pulp web into the suction roll.