Abstract: The invention relates to method and apparatus for removing the flaps from a perforated web of paper by drawing the perforated web over an abrasively surfaced drum rotating in the same direction as the paper is traveling and at a peripheral speed about seven times greater than the speed of the web. The web is passed over the drum such that the flaps are at the leading or downstream edges of the perforations and lie between the paper and the drum. A spring-biased pressure yoke holds the perforated web against the drum surface with a predetermined amount of pressure to facilitate abrading the flaps from the web.

Abstract: An apparatus and method for slitting an endless strip of material having substantially planar surfaces by forming a pair of adjacent grooves in each surface of the material with corresponding grooves in each surface of the material being orthogonally aligned and applying a force normal to the planar surfaces of the material and between adjacent grooves and of sufficient magnitude to shear the material along a line connecting corresponding grooves. For this purpose a pair of scoring knives for each slit are mounted in relative orthogonal alignment with respect to the planar surfaces of the material with one on each side of the material. The knives form the adjacent grooves in each surface of the material.

Abstract: The permeability of a moving web, for example, of perforated cigarette tipping paper, is monitored by inducing a fluid flow across the web, measuring the pressure drop across the web, independently measuring the volumetric flow rate, and calculating the permeability in CORESTA units. This method is embodied in apparatus which sequentially measures the instantaneous permeability of successive areas on the web to provide direct indication of the instantaneous CORESTA permeability.