1. Field of the Invention
The present invention relates to method for the manufacture or treatment of a material web, in particular of a paper or cardboard web, while using a respective machine, in particular a paper machine. The present invention further relates to an apparatus for measuring the hardness and/or the compactness of at least one clothing, in particular, of at least one felt, fabric, belt and/or the like, of a machine, in particular, of a paper machine, for the manufacture or treatment of a material web, in particular of a paper or cardboard web.
2. Description of the Related Art
Previous technologies for studying machine clothing involved online studies of moisture and/or permeability of machine clothing in order to determine their condition and performance. These studies were unable to provide information regarding the compaction (or density) of the machine clothing in cross direction or in machine direction over time. Apart from this, such measurements were unable to provide any indication of nip profile in situations where the clothing had passed through a pressing operation. A method of this kind is described, for example, in U.S. Pat. No. 5,611,893 and DE 691 29 788 T2.