	US 12,203,216 B2
	Method and device for the determination of the contamination of a suction roll of a machine for producing a fibrous web
Marc Erkelenz, Neu-Ulm (DE); and Jose Luiz Campos Souza, Heidenheim (DE)
Assigned to Voith Patent GmbH, Heidenheim (DE)
Appl. No. 17/619,101
Filed by Voith Patent GmbH, Heidenheim (DE)
PCT Filed May 12, 2020, PCT No. PCT/EP2020/063135 § 371(c)(1), (2) Date Dec. 14, 2021, PCT Pub. No. WO2020/249343, PCT Pub. Date Dec. 17, 2020.
Claims priority of application No. 102019116197.5 (DE), filed on Jun. 14, 2019.
Prior Publication US 2022/0267959 A1, Aug. 25, 2022
Int. Cl. D21F 3/10 (2006.01); B01D 35/143 (2006.01); D21F 7/00 (2006.01)

CPC D21F 3/10 (2013.01) [B01D 35/143 (2013.01); D21F 7/00 (2013.01)]

20 Claims

1. A method for determining contamination of a suction roller of a machine for producing a fibrous web, which comprises the following steps of:

a) causing a fluid to flow through a measuring area A of a roller shell, either a pressure or a flow rate of the fluid being kept constant;

b) determining a characteristic variable K, the characteristic variable K including the flow rate with a flow at a constant pressure and of a resultant pressure drop during a measurement with a constant flow rate;

c) providing at least one reference variable; and

d) determining a level of the contamination of the suction roller by comparing the characteristic variable K with the at least one reference variable.