Fluid flow filter and method of making and using

In a method of producing a filter, comprising:

• convoluting a non-woven fiber batt to produce at least one fiber filter sheet having a convoluted flow contact surface having a series of non-linear alternating rows of peaks and valleys, and which convoluting includes feeding the fiber batt between a pair of rotating tooling members and splitting said fiber batt into said at least one fiber filter sheet with the convoluted flow contact surface and at least one other fiber sheet, the improvement which comprises,
• in said step of convoluting said non-woven fiber batt, said non-woven fiber batt has a basis weight of between 1200 g/sqm to 1800 g/sqm, and
• wherein said at least one fiber filter sheet is comprised of a recipe of fibers with a majority of the fibers being coarse fibers, and wherein said non-woven fiber batt subjected to convoluting is a non-woven fiber batt having a thickness of 100 to 150 mm, and a majority of fibers 40 denier or greater.

In a method of producing a filter, comprising:

• convoluting a non-woven fiber batt to produce at least one fiber filter sheet having a convoluted flow contact surface having a series of alternating peaks and valleys and which convoluting includes feeding the fiber batt between a pair of rotating tooling members and splitting said fiber batt into said at least one fiber filter sheet and a second fiber filter sheet each with respective convoluted flow contact surfaces, the improvement which comprises,
• convoluting a non-woven fiber batt that has a basis weight of between 1200 g/sqm to 1800 g/sqm with a thickness of 3.0 to 8.0 inches, and wherein said at least one fiber filter sheet has 30% or more of fibers ranging from 15 to 100 denier, and wherein said non-woven fiber batt subjected to convoluting has a thickness of 100 to 150 mm, and a majority of fibers of 40 denier or greater.