A method of identifying a defect in a wet film comprises conveying said wet film (20), in a wet state, on a conveyor (10), providing a laser projection (1511) onto the wet film, acquiring a series of images, each depicting an area of the wet film, wherein at least a portion of the laser projection is visible, and using at least some of said images to identify said defect. There is also disclosed a method and device for producing a film.

A method of identifying a defect in a wet film comprises conveying said wet film (20), in a wet state, on a conveyor (10), providing a laser projection (1511) onto the wet film, acquiring a series of images, each depicting an area of the wet film, wherein at least a portion of the laser projection is visible, and using at least some of said images to identify said defect. There is also disclosed a method and device for producing a film.

The present document discloses a method of determining thickness of a wet film, in particular of microfibrillated cellulose. The method comprises conveying said film (20) in a wet state on a conveyor (10) having a conveyor width, the wet film having a film width which is less than the conveyor width, providing a laser projection (1511) across a film edge, acquiring a series of images, each depicting an area of the conveyor, wherein the laser projection, a portion of the film and a portion of an exposed conveyor surface are visible, and using at least some of said images to determine at least one of a film thickness and a film thickness distribution across the film width. The document also discloses a method of forming a film, in particular a microfibrillated cellulose film, and a device for producing such film.

An apparatus including a caliper measuring sensor arrangement, a mass measuring sensor arrangement, and a stabilizing arrangement. The caliper measuring sensor arrangement measures caliper of the web. The mass measuring sensor arrangement measures at least one of the following: a basis weight of the web, a moisture content, a water weight, dry weight of the web. The stabilizing arrangement stabilizes the web. The stabilizing arrangement including at least a part of the mass measuring sensor arrangement.

An apparatus including a caliper measuring sensor arrangement, a mass measuring sensor arrangement, and a stabilizing arrangement. The caliper measuring sensor arrangement measures caliper of the web. The mass measuring sensor arrangement measures at least one of the following: a basis weight of the web, a moisture content, a water weight, dry weight of the web. The stabilizing arrangement stabilizes the web. The stabilizing arrangement including at least a part of the mass measuring sensor arrangement.

A sheet manufacturing apparatus includes a defibrating unit configures to defibrate a raw material containing fiber into a defibrated material; a screening unit configured to screen the defibrated material that is defibrated by the defibrating unit; a web forming unit configured to form a web on which the defibrated material screened by the screening unit is deposited; a rotary body that includes a protrusion unit for forming a subdivided body by dividing the web formed by the web forming unit; a deposition unit configures to deposit the defibrated material configuring the subdivided body; and a forming unit configured to form the sheet by pressurizing and heating the defibrated material deposited by the deposition unit.

A sheet manufacturing apparatus includes a defibrating unit configures to defibrate a raw material containing fiber into a defibrated material; a screening unit configured to screen the defibrated material that is defibrated by the defibrating unit; a web forming unit configured to form a web on which the defibrated material screened by the screening unit is deposited; a rotary body that includes a protrusion unit for forming a subdivided body by dividing the web formed by the web forming unit; a deposition unit configures to deposit the defibrated material configuring the subdivided body; and a forming unit configured to form the sheet by pressurizing and heating the defibrated material deposited by the deposition unit.

Collecting data includes generating a sensor signal from each of a plurality of sensors located on a sensing roll, wherein each signal is generated when each sensor enters a region of a nip between the sensing roll and mating roll during each rotation of the sensing roll; wherein a web of material travels through the nip and a continuous band contacts a region of the web of material upstream from or at the nip. A periodically occurring starting reference is generated associated with each rotation of the continuous band and the signal generated by each sensor is received so that the one of the plurality of sensors which generated this signal is determined and one of a plurality of tracking segments associated with the continuous band is identified. The signal is stored to associate the respective sensor signal with the identified one tracking segment.

Collecting data includes generating a sensor signal from each of a plurality of sensors located on a sensing roll, wherein each signal is generated when each sensor enters a region of a nip between the sensing roll and mating roll during each rotation of the sensing roll; wherein a web of material travels through the nip and a continuous band contacts a region of the web of material upstream from or at the nip. A periodically occurring starting reference is generated associated with each rotation of the continuous band and the signal generated by each sensor is received so that the one of the plurality of sensors which generated this signal is determined and one of a plurality of tracking segments associated with the continuous band is identified. The signal is stored to associate the respective sensor signal with the identified one tracking segment.

A method for creping paper includes applying an adhesive composition to an outer surface of a creping cylinder (Yankee cylinder) to form an adhesive coating, contacting paper with the adhesive coating, removing the paper and adhesive coating from the creping cylinder, and determining a quality of the adhesive coating. Determining the quality of the adhesive coating may include measuring a degree of cross-linking of the adhesive polymer, a concentration of the adhesive polymer in the adhesive coating, a water content of the adhesive coating, an ash content of the adhesive coating, or combinations thereof. Determining the quality of the adhesive coating may also include determining a thickness of the adhesive coating by measuring light absorbed by the coating and calculating the thickness using Beer's Law. Systems and apparatuses for determining the quality of the adhesive coating and for creping paper are also disclosed.