The present disclosure relates to a vacuum dewatering apparatus comprising a vacuum box disposed opposite of a steam box where the steam box comprises a bottom plate having a substantially linear portion and a curvilinear portion. A plurality of apertures are disposed along at least a portion of the curvilinear portion to permit the transmission of steam. In a preferred embodiment, the curvilinear portion is adjacent to the trailing edge and the linear portion is adjacent to the leading edge of the apertured bottom plate. Further, at least a portion of the apertures are aligned opposite the vacuum box which acts to remove the steam. The vacuum dewatering apparatus of the present invention enables the use of high levels of steam improving vacuum dewatering and improving drying efficiency.

The invention relates to a suction device (15) for use in a papermaking machine and being suitable for acting on a wet fibrous web through a permeable fabric (4, 6), e.g. a through-air-drying (TAD)-fabric. The suction device has a fabric-facing surface (18) formed by a plurality of end surfaces of solid elements (21, 22). Channels (24, 25) are defined between the solid elements. The end surface of the final solid element (22) does not lie in the same plane as the end surfaces of the previous solid elements (21). Thereby, a gap A is formed between the fabric (4, 6) and the final solid element (22). This allows air to flow through the gap and into a final channel (25). The air flow will then catch fines, small fibers and water droplets and draw them into the final channel (25) thereby counteracting a build-up of large lumps of fines and fibers.

The invention relates to a suction device (15) for use in a papermaking machine and being suitable for acting on a wet fibrous web through a permeable fabric (4, 6), e.g. a through-air-drying (TAD)-fabric. The suction device has a fabric-facing surface (18) formed by a plurality of end surfaces of solid elements (21, 22). Channels (24, 25) are defined between the solid elements. The end surface of the final solid element (22) does not lie in the same plane as the end surfaces of the previous solid elements (21). Thereby, a gap A is formed between the fabric (4, 6) and the final solid element (22). This allows air to flow through the gap and into a final channel (25). The air flow will then catch fines, small fibers and water droplets and draw them into the final channel (25) thereby counteracting a build-up of large lumps of fines and fibers.

The invention relates to a suction device (15) for use in a papermaking machine and being suitable for acting on a wet fibrous web through a permeable fabric (4, 6), e.g. a through-air-drying (TAD)-fabric. The suction device has a fabric-facing surface (18) formed by a plurality of end surfaces of solid elements (21, 22). Channels (24, 25) are defined between the solid elements. The end surface of the final solid element (22) does not lie in the same plane as the end surfaces of the previous solid elements (21). Thereby, a gap A is formed between the fabric (4, 6) and the final solid element (22). This allows air to flow through the gap and into a final channel (25). The air flow will then catch fines, small fibers and water droplets and draw them into the final channel (25) thereby counteracting a build-up of large lumps of fines and fibers.

The invention relates to a suction device (15) for use in a papermaking machine and being suitable for acting on a wet fibrous web through a permeable fabric (4, 6), e.g. a through-air-drying (TAD)-fabric. The suction device has a fabric-facing surface (18) formed by a plurality of end surfaces of solid elements (21, 22). Channels (24, 25) are defined between the solid elements. The end surface of the final solid element (22) does not lie in the same plane as the end surfaces of the previous solid elements (21). Thereby, a gap A is formed between the fabric (4, 6) and the final solid element (22). This allows air to flow through the gap and into a final channel (25). The air flow will then catch fines, small fibers and water droplets and draw them into the final channel (25) thereby counteracting a build-up of large lumps of fines and fibers.

A method for monitoring a wear structure including at least one wear element in a machine for generating or processing a fibrous material web, includes providing a time at which the wear element became operational, providing a time at which a defined first wear level of the wear element was reached, providing at least one further characteristic variable, and predicting a remaining operating time of the wear element from the knowledge of the times, in particular from a time difference between the times, as well as from the at least one further characteristic variable, by using a computer system. A device for carrying out the method is also provided.

A method for monitoring a wear structure including at least one wear element in a machine for generating or processing a fibrous material web, includes providing a time at which the wear element became operational, providing a time at which a defined first wear level of the wear element was reached, providing at least one further characteristic variable, and predicting a remaining operating time of the wear element from the knowledge of the times, in particular from a time difference between the times, as well as from the at least one further characteristic variable, by using a computer system. A device for carrying out the method is also provided.

A sheet manufacturing apparatus includes a first transport unit, a second transport belt disposed with a part thereof shifted from the first transport unit toward the downstream side in a transport direction of the web, a suction chamber positioned in an inner side of the second transport belt and configured to create suction inside the suction chamber to suck the web onto the second transport belt, and a current plate positioned inside of the suction chamber to adjust an air current. The current plate has a plurality of holes, and is spaced apart from a surface of the second transport belt such that the air current is diffused between the current plate and the surface of the second transport belt to achieve a uniform suction force in a width direction of the second transport belt.

Disclosed is a sheet manufacturing apparatus including a rotatable drum unit in which a plurality of openings are formed; a web forming unit that forms a web by using a material containing fibers passing through the openings; a housing unit that covers at least a portion of the drum unit in which the openings are formed; a material supply port that is provided to supply the material in a direction along a rotational axis of the drum unit to the inside of the drum unit by airflow; and an air intake port that is provided to supply air that does not contain the material in the direction along the rotational axis of the drum unit to the inside of the drum unit. The web forming unit includes a mesh belt on which the material is deposited and a suction unit that sucks the material onto the mesh belt.

Disclosed is a sheet manufacturing apparatus including a rotatable drum unit in which a plurality of openings are formed; a web forming unit that forms a web by using a material containing fibers passing through the openings; a housing unit that covers at least a portion of the drum unit in which the openings are formed; a material supply port that is provided to supply the material in a direction along a rotational axis of the drum unit to the inside of the drum unit by airflow; and an air intake port that is provided to supply air that does not contain the material in the direction along the rotational axis of the drum unit to the inside of the drum unit. The web forming unit includes a mesh belt on which the material is deposited and a suction unit that sucks the material onto the mesh belt.