Porosity Measurement of Press Felts on the Paper Machine (HSPT), Technical Information Paper TIP 0404-29 (2004) WITHDRAWN


This Technical Information Paper1 describes a test procedure for the measurement of relative airflow through a felt running on the paper machine.

Correlation between Huyck-Smyth Porosity Tester (HSPT) readings and void volume (1) and between HSPT readings and water removal (2,3) have been reported. This tester has been used by numerous mills to monitor changes in felt porosity throughout its life.


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