A plant for producing corrugated cardboard. The plant includes an arrangement for producing a corrugated cardboard web laminated on one side, the arrangement having a corrugating apparatus for generating a corrugated web, which has a corrugation, from a first material web, having a glue-applying apparatus for applying glue to tips of the corrugation of the corrugated web, and having a pressing apparatus for pressing a top web onto the tips, provided with glue, of the corrugated web. The plant furthermore has a severing apparatus which is arranged upstream of the corrugating apparatus and which serves for at least regionally severing the first material web in the transverse direction thereof.

A drum covering for a drive drum (21) in a corrugating machine has a textile carrier material that reversibly shrinks when heated up, said carrier material being coated on at least one side with a coating material. Furthermore, it has two rectangular regions (71, 72) that are each connected to a convexly deltoid-shaped region (6) on a narrow side. Sets for producing the drum covering contain several covering pieces. A drive drum provided with the drum covering can be produced by the central axis (M) of the convexly deltoid-shaped region (6) being arranged along the circumferential central axis of the drive drum (21). Then, the convexly deltoid-shaped region (6) is fixed on the drive drum surface by means of at least one fixing element. The drive drum (21) is rotated, wherein the rectangular regions (71, 72) of the drum covering are wound around the drive drum (21) in a spiral-shaped manner. The rectangular regions (71, 72) are cut off on the ends of the drive drum (21) and the ends of the rectangular regions (71, 72) are fixed on the drive drum surface by means of further fixing elements. This drive drum can be installed in a corrugating machine in such a way that the rectangular regions (71, 72) are wound around the drive drum against the rotational direction of the drive drum (21) when the corrugating machine is in operation.

An apparatus for introducing transverse trapezoidal corrugations into a traveling web is provided, and includes a plurality of corrugating rollers for imparting corrugations to the web. In disclosed embodiments four such rollers are provided in a roller train defining respective first, second and third nips therebetween, wherein the teeth of the first and second rollers have rounded distal faces and those of the third and fourth rollers have flattened distal faces. Methods of yielding a trapezoidal corrugated web also are disclosed.

A plant for producing corrugated cardboard. The plant includes an arrangement for producing a corrugated cardboard web laminated on one side, the arrangement having a corrugating apparatus for generating a corrugated web, which has a corrugation, from a first material web, having a glue-applying apparatus for applying glue to tips of the corrugation of the corrugated web, and having a pressing apparatus for pressing a top web onto the tips, provided with glue, of the corrugated web. The plant furthermore has a severing apparatus which is arranged upstream of the corrugating apparatus and which serves for at least regionally severing the first material web in the transverse direction thereof.

A drum cover (20a-c) for a drive drum (12) of a corrugated cardboard machine has a textile carrier layer (21), which has a first coating (22) on a first side and a second coating (23) on a second side. The second coating (23) has a glass transition temperature in the range of 20 C. to 60 C.

The plant includes at least one single facer, having a supporting structure, adapted to receive a corrugating unit provided with a first corrugating roller and a second corrugating roller meshing with each other. The plant also includes a magazine having a plurality of seats for receiving corrugating units and movable along a first guide. Associated with the single facer there is provided a shuttle movable between the single facer and the guide of the magazine, adapted to transfer corrugating units from the single facer to the magazine and vice versa.

A single facer comprises: a swingable frame supporting a press roll in such a manner as to allow a gap between one of a pair of corrugating rolls and the press roll to be changed; an adjusting screw contactable with a contact member coupled to the swingable frame; an encoder for detecting vibration of the press roll occurring during formation of a corrugated medium by the pair of corrugating rolls; and a control section for controlling drive of a motor for displacing the adjusting screw. The control section is configured to execute a first control processing of driving the motor until a magnitude of the vibration is reduced to a given value.

An apparatus for introducing transverse trapezoidal corrugations into a traveling web is provided, and includes a plurality of corrugating rollers for imparting corrugations to the web. In disclosed embodiments four such rollers are provided in a roller train defining respective first, second and third nips therebetween, wherein the teeth of the first and second rollers have rounded distal faces and those of the third and fourth rollers have flattened distal faces. Methods of yielding a trapezoidal corrugated web also are disclosed.

A single facer including a first corrugating roller with a first rotation axis and a second corrugating roller with a second rotation axis. The two corrugating rollers form a corrugating nip, through which a paper sheet passes. The single facer also includes a pressing member, co-acting with the second corrugating roller and forming a pressure nip therewith, as well as a glue applicator co-acting with the second corrugating roller. With the second corrugating roller a suction box is associated, 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 the annular grooves of the second corrugating roller, are arranged between the pressing member and the first corrugating roller and extend in the respective annular grooves towards the suction box.

An apparatus for introducing transverse trapezoidal corrugations into a traveling web is provided, and includes a plurality of corrugating rollers for imparting corrugations to the web. In disclosed embodiments four such rollers are provided in a roller train defining respective first, second and third nips therebetween, wherein the teeth of the first and second rollers have rounded distal faces and those of the third and fourth rollers have flattened distal faces. Methods of yielding a trapezoidal corrugated web also are disclosed.