Patent ID: 6309552
Filing Date: 2001-10-30
Classification: B01D,Y10S,Y10T

Abstract:
A method of fabricating a filter tube comprising:forming a length of flexible fluid permeable tubular sheet including a plurality of woven groups of strands, said tubular sheet having a supported end and an unsupported end;inserting a helical spring having opposed inner and outer ends within the remote tubular sheet end;positioning the inner spring end at the supported sheet end, the length of said helical spring in a relaxed state being substantially shorter than the length of the tubular sheet;aligning the opposed ends of the spring while said spring is in said relaxed state with the supported and unsupported ends of the tubular sheet by compressing the tubular sheet;fixing the aligned inner end of the spring to the supported tubular sheet end;sealing the aligned outer end of the spring to the remote tubular sheet end by inserting a deformable member having an open end and a closed end inside the outer end of the helical spring, and inserting a threadable member into the open end of the deformable member to form a seal between the threadable member and the deformable member and the tubular sheet, such that the tubular sheet is slack when the spring is in said relaxed state.