Abstract: A sound attenuating apparatus for noise bearing fluid streams wherein elongated perforated wall forming panel sheets include integrally formed indentations extending along a direction transverse the direction of the fluid stream to provide strength and stiffeners for the perforated panel sheets.

Abstract: A unique pulse-jet cartridge type particulate collector structure and method wherein horizontally disposed particulate filter cartridges are suspendedly disposed in a particulate separation chamber defined by an outer wall so that opposite ends of the suspended particulate filter cartridges are spaced from the opposed inner faces of the outer wall with dirty gas flow being delivered from a dirty gas inlet in the outer wall through the particulate filter cartridges in a smooth manner by a large particulate particle deflector and with the particulate hopper connected to the lower section of the outer wall having a transparent particulate catching container removably sealed in communicative relation with the particulate release opening of the particulate hopper.

Abstract: A pleated filter medium arrangement including a sheet of pleated porous filtering media nestingly engaged between adjacent pleats by a pleated sheet of thermobondable plastic screening with preselected facing opposite portions of the screening being heat bonded together.

Abstract: An apparatus and method for distributing pressurized fiber attenuating fluid through a melt blowing multi-headed die body uniformly and contaminant filtered with a minimum of energy loss before reaching the fluid attenuating outlets of the die body.

Abstract: A sound attenuating apparatus and method for forming the same including stacking selectively sized sheets of sound attenuating materials and fastening the same to form elongated, perforated sound attenuating flow-through passages which are structurally connected by means of mechanical joinders outside the noise bearing fluid stream to be attenuated.

Abstract: A fluid filter arrangement including layered filter media capable of successively filtering varying sized particulate matter from a treated fluid stream with each layer of the layered filter media having a substantially equal terminal pressure drop thereacross.

Abstract: A particulate filter for a fluid stream being of preselected thickness with progressively increasing fibrous density from the upstream face toward the downstream face, the filter having a transversely and uniformly extending planar sheet-like adhesive barrier at a preselected location and quantity between the upstream and downstream faces thereof.