Measurement of elastic modulus of moving web

Patent metadata

Field	Value
Publication number	US-11828736-B2
Application number	US-201917052537-A
Country	US
Kind code	B2
Filing date	Apr 24, 2019
Priority date	May 3, 2018
Publication date	Nov 28, 2023
Grant date	Nov 28, 2023

Abstract

According to an example aspect of the present invention, there is provided a method, comprising: controlling suction with predetermined force in a known measurement area to a moving cardboard or paper web in a manufacturing process, detecting on-line measurement information on deviation of the moving cardboard or paper web in the manufacturing process caused by the suction with predetermined force in the known measurement area, and determining elastic modulus of the moving cardboard or paper web in the manufacturing process on the basis of the measured deviation.

First claim

The invention claimed is:

1. An apparatus, comprising:
a suction unit configured for applying suction with a predetermined force in a known measurement area to a moving cardboard or paper web in a manufacturing process,
a deviation sensing unit configured for on-line measurement of deviation of the moving cardboard or paper web in the manufacturing process caused by the applied suction in the known measurement area, wherein the deviation sensing unit comprises a three-dimensional scanners configured to define three-dimensional surface profile of the cardboard or paper web in the measurement area and store a set of coordinate points forming a point cloud, and
a computing unit configured for determining elastic modulus of the moving cardboard or paper web on the basis of the three-dimensional surface profile.

2. The apparatus of claim 1 , wherein at least deviation sensing unit is provided in a measurement unit arranged to move in cross direction to the movement of the cardboard or paper web.

3. The apparatus of claim 1 , wherein the apparatus further comprises a further suction unit for applying suction to the moving cardboard or paper web to cause the moving cardboard or paper web to move against a supporting surface of a plane of the apparatus on at least one side of the known measurement area.

4. The apparatus of claim 1 , wherein the apparatus further comprises at least one measurement plate to be applied against the moving cardboard or paper web and comprising at least one hole for applying suction to the moving cardboard or paper web.

5. The apparatus of claim 4 , wherein the measurement plate is rotatable in relation to the moving cardboard or paper web.

6. The apparatus of claim 1 , wherein the suction unit comprises a set of selectable suction levels for applying suction to the moving cardboard or paper web.

7. The apparatus of claim 1 , wherein the suction unit and the deviation sensing unit are provided at opposite sides of the moving cardboard or paper web.

8. The apparatus of claim 1 , wherein the apparatus comprises a computing unit configured to determine a value indicative of strain of the moving cardboard or paper web in the direction of movement of the web, wherein the computing unit is configured to calculate the elastic modulus on the basis of the determined value indicative of the strain.

9. The apparatus of claim 1 , wherein the apparatus is a paper or cardboard production machine or is to be included in a paper or cardboard production machine, wherein the apparatus is adapted for measuring end product properties in the cardboard or paper web manufacturing process.

10. The apparatus of claim 1 , wherein the apparatus is configured to measure an area which extends outside said known measurement area.

11. A method for measurement of elastic modulus of a moving cardboard or paper web, comprising:
controlling suction with predetermined force in a known measurement area to a moving cardboard or paper web in a manufacturing process,
detecting on-line measurement information on deviation of the moving cardboard or paper web in the manufacturing process caused by the suction with predetermined force in the known measurement area, wherein a three-dimensional surface profile of the cardboard or paper web in the measurement area is provided and a set of coordinate points forming a point cloud is stored, and
determining elastic modulus of the moving cardboard or paper web in the manufacturing process on the basis of the three-dimensional surface profile.

12. The method of claim 11 , wherein suction is applied to the moving cardboard or paper web for causing the moving cardboard or paper web against a surface on at least one side of the known measurement area.

13. The method of claim 11 , wherein an area which extends outside said known measurement area is measured.

14. A non-transitory computer readable medium, comprising computer program code for, when executed in a processor of a computing device for an elastic modulus measurement system, causing the computing device at least to:
control suction by a suction unit with predetermined force in a known measurement area to a moving cardboard or paper web in a manufacturing process,
detect from a deviation sensing unit on-line measurement information on the deviation of the moving cardboard or paper web in the manufacturing process caused by the suction with predetermined force in the known measurement area, wherein a three-dimensional profile of the cardboard or paper web in the measurement area is provided and a set of coordinate points forming a point cloud is stored, and
determine elastic modulus of the moving cardboard or paper web in the manufacturing process on the basis of the three-dimensional surface profile.

Assignees

• Valmet Automation Oy

Inventors

• Mäntylä Markku
• Graeffe Jussi
• Erkkilä Anna-Leena

Classifications

• G01N3/20 Primary

  by applying steady bending forces (G01N3/26, G01N3/28 take precedence) · CPC title

• B65H23/044

  Sensing web tension (B65H23/06, B65H23/18 take precedence) · CPC title

• D21F1/48

  Suction apparatus (suction rolls D21F3/10) · CPC title

• D21G9/0027

  controlling the forming section · CPC title

• G01B11/06

  for measuring thickness {; e.g. of sheet material (thickness measurement by thermal means G01B21/085)} · CPC title