TAPPI T248 sp-21 PDF

This standard practice describes the processing of pulp by means of the PFI mill (1) to evaluate pulp quality for papermaking.
In principle, the standard practice applies to all types of pulp; in practice, the method may not give satisfactory results with certain very long-fiber pulps such as cotton.
The standard practice is suited to processing small quantities of test specimens that are too small for processing in the Valley beater, as described in TAPPI T 200 Laboratory Processing of Pulp (Beater Method).