Single facer for producing single face corrugated paperboard, and related method

A single facer comprising:

• a first corrugating roller with a first rotation axis and a side surface provided with a series of flutes;
• a second corrugating roller with a second rotation axis and a side surface provided with a series of flutes;
• wherein the first corrugating roller and the second corrugating roller form a corrugating nip therebetween;
• and wherein the second corrugating roller comprises a series of annular grooves;
• a pressing member, co-acting with the second corrugating roller and forming a pressure nip therewith;
• a glue applicator, co-acting with the second corrugating roller;
• a suction box extending approximately parallel to the second rotation axis of the second corrugating roller and defining a suction area around the second corrugating roller;
• a series of laminar members, each of which is inserted in a respective one of said annular grooves of the second corrugating roller, the laminar members being arranged between the pressing member and the first corrugating roller and extending in respective ones of the annular grooves towards the suction box, such as to provide a sealing inside the annular grooves directly upstream of the suction box with respect to a direction of rotation of the second corrugating roller;
• wherein a sealing member is associated with the suction box and co-acts with the flutes of the second corrugating roller;
• and wherein the laminar members extend inside the annular grooves under the sealing member.

A single facer comprising:

• a first corrugating roller with a first rotation axis and a side surface provided with a series of flutes;
• a second corrugating roller with a second rotation axis and a side surface provided with a series of flutes;
• wherein the first corrugating roller and the second corrugating roller form a corrugating nip therebetween;
• and wherein the second corrugating roller comprises a series of annular grooves;
• a pressing member, co-acting with the second corrugating roller and forming a pressure nip therewith;
• a glue applicator, co-acting with the second corrugating roller;
• a suction box extending approximately parallel to the second rotation axis of the second corrugating roller and defining a suction area around the second corrugating roller;
• a series of laminar members, each of which is inserted in a respective one of said annular grooves of the second corrugating roller, the laminar members being arranged between the pressing member and the first corrugating roller and extending in respective ones of the annular grooves towards the suction box, such as to provide a sealing inside the annular grooves directly upstream of the suction box with respect to a direction of rotation of the second corrugating roller;
• wherein a sealing member is associated with the suction box and co-acts with the flutes of the second corrugating roller;
• and wherein the suction box and the sealing member are supported by a crossbar approximately parallel to the second rotation axis of the second corrugating roller and wherein the laminar members are carried on the crossbar.

A single facer comprising:

• a first corrugating roller with a first rotation axis and a side surface provided with a series of flutes;
• a second corrugating roller with a second rotation axis and a side surface provided with a series of flutes;
• wherein the first corrugating roller and the second corrugating roller form a corrugating nip therebetween;
• and wherein the second corrugating roller comprises a series of annular grooves;
• a pressing member, co-acting with the second corrugating roller and forming a pressure nip therewith;
• a glue applicator, co-acting with the second corrugating roller;
• a suction box extending approximately parallel to the second rotation axis of the second corrugating roller and defining a suction area around the second corrugating roller;
• a series of laminar members, each of which is inserted in a respective one of said annular grooves of the second corrugating roller, the laminar members being arranged between the pressing member and the first corrugating roller and extending in respective ones of the annular grooves towards the suction box, such as to provide a sealing inside the annular grooves directly upstream of the suction box with respect to a direction of rotation of the second corrugating roller;
• wherein a sealing member is associated with the suction box and co-acts with the flutes of the second corrugating roller;
• and wherein each of the laminar members has a radially outer edge in contact with the sealing member.