Abstract: The quality measurement method for a long sheet material W includes measuring cellulose fibers, % moisture, and % ash of the paper web W by using area cameras 1102 to 1106 having an infrared light receiving element and a light source 1100 having an infrared light emitting LED element. Performance check for the infrared cameras 1102 to 1106 over the entire width and correction of measured values are performed by using consistency between measured values for the same point in an overlap area measured by adjacent cameras and reference samples 1107 at the off-sheet positions provided at both sides.

Abstract: The quality measurement method for a long sheet material W includes measuring cellulose fibers, % moisture, and % ash of the paper web W by using area cameras 1102 to 1106 having an infrared light receiving element and a light source 1100 having an infrared light emitting LED element. Performance check for the infrared cameras 1102 to 1106 over the entire width and correction of measured values are performed by using consistency between measured values for the same point in an overlap area measured by adjacent cameras and reference samples 1107 at the off-sheet positions provided at both sides.

Abstract: A method of measuring the thickness of long sheet material wound on to a reel spool while being pressed by a reel drum, includes: measuring the increase in the roll diameter of the wound roll formed from the long sheet material in a non-contact manner; measuring the number of rotations of the reel spool; and determining the thickness of the long sheet material by calculation using the measured increase in the roll diameter and the number of rotations.

Abstract: [PROBLEM] To provide a method of measuring the thickness of long sheet material and a thickness measuring system, that measures the thickness of paper separately for a component in a machine direction and a component in a cross direction without scanning or filtering, that does not require a conventional basis weight sensor using a radioisotope and can be applied even to small paper machines. [SOLUTION] The method of measuring the thickness of long sheet material W wound on to a reel spool 16 while being pressed by a reel drum 12, includes: measuring the increase in the roll diameter of a wound roll R formed from the long sheet material W in a non-contact manner; measuring the number of rotations of the reel spool 16; and determining the thickness of the long sheet material by calculation using the measured increase in the roll diameter and the number of rotations.