Abstract: The invention relates to a shredding apparatus for use in shredding a material mass into a plurality of discrete particles. The principal components includes a shredding screen and wiper blades. The wiper blade include a semi-rigid blade having its lower end in firm contact with said shredding screen. Reciprocating means is fixed to the shredding screen means to provide reciprocating motion of the shredding screen relative to said wiper blade. The reciprocating means produces a length of travel of said shredding screen at least equal to the space between an adjacent pair of wiper blades. Each of said wiper blades are parallel to each other and to a first set of spaced parallel bars. A second set of spaced parallel bars are substantially perpendicular to the first set of spaced parallel bars thereby forming a plurality of openings having a predetermined cross-sectional area substantially equal to the required cross-sectional area of said discrete particles.

Abstract: In accordance with the present invention, the imminent failure of a diaphragm due to the attack by a corrosive or a solvent or mechanical fatigue is predicted through the use of a diaphragm pump having a housing, a first chamber within the housing, a second chamber within the housing and a diaphragm mounted in the housing between the first chamber and the second chamber. The diaphragm is of a chemically inert, electrically non-conductive material which contains an interconnected, electrically conductive material extending within the diaphragm less than the full radial dimension of the diaphragm. The conductive material is approximately equally spaced from the two opposing surfaces of the diaphragm. The electrically conductive material is advantageously, an electrically conductive graphite and takes the form of a mesh, screen or web of conductive fibers, filaments or strands.