Segmented Flange Ring: flat pattern
A flat ring, as a flange, a stiffener or a base ring, made in equal segments so that it nests on the plate, with or without its bolt holes. A flat ring, as a flange, a stiffener or a base ring, made in equal segments so that it nests on the plate, with or without its bolt holes.
Open the segmented flange ring in SheetMorphConfigurations
- Plain ring. The segments alone.
- With bolt holes. The bolt holes are marked on each segment, equally spaced on their pitch circle, with a joint midway between two holes.
A worked example
The plain ring configuration with the sizes SheetMorph opens with, in mm. 4 segments, all alike: 4 parts, 4 seams.
| Blank of P1 | 707.1 mm × 217.2 mm |
| Blank of P2 | 707.1 mm × 217.2 mm |
| Blank of P3 | 707.1 mm × 217.2 mm |
| Blank of P4 | 707.1 mm × 217.2 mm |
| Length of cut, every outline and hole | 6445.8 mm |
| Outside diameter | 1000.00 mm |
| Inside diameter | 800.00 mm |
| Width of the ring | 100.00 mm |
| Area of the whole ring | 282,743 mm² |
| Number of segments | 4 |
| Angle of each | 90.00 ° |
| Chord across its outer corners | 707.11 mm |
| Chord across its inner corners | 565.69 mm |
| Height of the rectangle it is cut from | 217.16 mm |
| Length of its outer edge | 785.40 mm |
| Length of its inner edge | 628.32 mm |
| P1 Segment 1, long | 707.11 mm |
| P1 Segment 1, wide | 217.16 mm |
| Plates | 4 |
| Triangular facets | 64 |
| Pattern extent X | 3358.76 mm |
| Pattern extent Y | 217.16 mm |
| Developed area | 280,930 mm² |
| Total cut length | 6445.79 mm |
| Longitudinal seam length | 0.00 mm |
How it is developed
True shape of a flat plate. This is an exact development: the surface unfolds without stretching, so the pattern closes exactly.
- The ring is cut in 4 equal segments of 90 degrees. Each fits a rectangle 707.1068 by 217.1573, and they nest one inside the next along a strip of plate.
- Set a segment out from its two chords, or from the radii struck from one centre. Cut one and use it as the template for the others.
Checked before it can be exported
Every pattern SheetMorph draws is checked against the 3D part it comes from. For this example:
- Surface connectivity (passed): 64 facets form a flat ring: every edge inside a part joins exactly two facets, every open edge one (V - E + F = 0).
- Developed edges equal true 3D lengths (passed): 192 facet edges compared between the 3D surface and the flat pattern (max deviation 4.41e-13).
- Shared edges and seam closure (passed): 60 internal edges are shared vertex-for-vertex between adjacent facets; 0 seam(s) have mating edges of equal true length (max deviation 0).
- Developed facets consistently oriented (passed): All developed facets are counter-clockwise (outside face up); none is mirrored or degenerate.
- Developed area equals surface area (passed): Facet area in 3D and in the flat pattern agree (difference 5.82e-11).
- Cut outlines closed and non-overlapping (passed): 4 closed outline(s); no outline crosses itself or another outline.
Assumptions
- The pattern is developed on the mid-thickness surface; inside or outside sizes are converted to it by the thickness.
- Curves are chains of chords between division points.
- No seam, lap, weld-preparation or pressing allowance is added.
Limits of this module
- The ring is flat plate, so the pattern is its true shape and the reference of the sizes makes no difference: the thickness is used for the weight only.
- The joints are radial butt joints; no weld preparation is drawn and no allowance is left for machining the ring after welding.
- A ring rolled on edge from flat bar is not this part: use the rolled ring for its length.
- Curves are chains of straight chords between division points.
- No seam, lap, weld-preparation or pressing allowance is added, and plates are not nested onto stock sheets.
Conventions
Coordinate system. The part stands on the Z axis with End A at Z = 0. Angles round the axis are measured from +X toward +Y, counter-clockwise seen from +Z.
Divisions and thickness. A circle is divided into 4N equal chords. Sizes are inside, mid-thickness or outside sizes; the pattern is developed on the mid-thickness surface and the views show the sizes as entered.
Ring. The ring lies flat in the XY plane, centred on the Z axis. Segment 1 starts on the +X axis and the others follow counter-clockwise seen from above; every segment is alike. End A is the inner edge and End B the outer edge, and the radial ends of the segments are the joints between them.
Bolt holes. The number of holes is for the whole ring and is shared equally among the segments. They are spaced evenly on the pitch circle, so that every joint falls midway between two holes and none is cut by a joint.
Change the sizes to your own in SheetMorph, check the drawing, add seam and flange allowances, and export DXF, PDF, SVG, CSV or G-code. Check every pattern against your own standards before cutting.
Open the segmented flange ringOther rings and helicals
- Rolled Bar: A ring, a hoop or part of one rolled from flat bar or strip: the length to cut on the neutral line, with the gap for the weld and the flat ends.
- Screw Flight: One flight of a screw conveyor or auger, right or left hand: standard, tapered or ribbon, as the flat blank that is pulled out to one pitch.
- Spiral Chute: A spiral chute: a floor that winds round an axis as it falls, with or without walls on its edges.
- Stair Stringer: The stringer of a spiral or helical stair: a plate rolled to stand on a cylinder as it climbs, alone or as a pair, with a line for every tread.