Filter discs and cut screens

The outside profile locates a disc in its holder; the exposed filtering field controls where the fluid crosses the medium. Draw both boundaries. A clamping land, folded rim or frame occupies part of the overall diameter, and the holder opening sets the usable flow window. On an annular disc, the centre opening introduces a second perimeter: define its diameter, concentricity to the outside profile and contact with the inner seat. This keeps the filtering field aligned with the equipment passage.

Specify the backing on the side that receives the pressure load. A coarse screen or perforated holder supports the fine layer across the open span, while the contact pattern determines where that layer remains exposed. Include the direction of normal flow and any reverse cleaning flow on the section drawing. For a rigid sintered disc, the face orientation, thickness and seating flatness join the same assembly definition; the nominal micron grade describes the chosen medium.

Outline and medium are separate choices. A circular, annular or shaped part can use a single woven layer, a retained multilayer stack or a bonded sintered structure. List each layer and its position before defining the outer edge. Spot welds hold the specified layers together during handling; a rolled rim encloses the perimeter and provides a repeatable gripping or seating surface. Place joining features and their thickness within the mounting land shown on the drawing.

For repeat orders, control the finished outline, inner cutouts, overall thickness and condition of both cut edges. Check that the medium reaches the entire active opening, that the retained layers remain registered and that the edge fits its holder without lifting the working face. Pack thin screens flat with their grade and layer sequence identified. Extruder screen packs use a separate inlet-to-outlet layer schedule matched to the breaker plate; that assembly information accompanies the disc outline.