Flange Box and End Cap: flat pattern
A removable box in two halves over a pair of insulated flanges, or the cap that closes the insulation where it ends on a pipe. A removable box over a pair of insulated flanges, its shell and its two ends made in halves to fit round the pipe, or the cap that closes the insulation where it ends on a pipe.
Open the flange box and end cap in SheetMorphConfigurations
- Flange box. A round box over a pair of flanges and the insulation round them, in two halves, its ends fitting over the jacket of the pipe either side.
- End cap. A flat ring that closes the end of the insulation, from the bare pipe out to the jacket, in two halves.
A worked example
The flange box configuration with the sizes SheetMorph opens with, in mm. Six plates, the two halves of the box: in each a half shell and its two half ends, alike in pairs: 6 parts, 2 seams.
| Blank of P1 | 385.7 mm × 192.9 mm |
| Blank of P2 | 385.7 mm × 192.9 mm |
| Blank of P3 | 604.9 mm × 300.7 mm |
| Blank of P4 | 385.7 mm × 192.9 mm |
| Blank of P5 | 385.7 mm × 192.9 mm |
| Blank of P6 | 604.9 mm × 300.7 mm |
| Length of cut, every outline and hole | 8194.5 mm |
| Pipe outside diameter | 168.30 mm |
| Outside of the insulation | 268.30 mm |
| Flange outside diameter | 285.00 mm |
| Inside diameter of the box | 385.00 mm |
| Hole in each end | 268.30 mm |
| Girth of a half shell | 605.86 mm |
| Length inside | 300.00 mm |
| Width of each end ring | 58.35 mm |
| P1 Half end A, 1, long | 385.70 mm |
| P1 Half end A, 1, wide | 192.85 mm |
| P3 Half shell 1, long | 604.88 mm |
| P3 Half shell 1, wide | 300.70 mm |
| Plates | 6 |
| Triangular facets | 192 |
| Pattern extent X | 3508.67 mm |
| Pattern extent Y | 300.70 mm |
| Developed area | 483,609 mm² |
| Total cut length | 8194.54 mm |
| Longitudinal seam length | 0.00 mm |
How it is developed
Development of a rolled half shell and flat half rings. This is an exact development: the surface unfolds without stretching, so the pattern closes exactly.
- The box is made in two halves that meet on a line through the axis, so it can be put on round the flanges and taken off for maintenance. The two halves are alike.
- The half shell unrolls to a rectangle half the girth of the box long; each end is a flat half ring from the hole out to the shell.
- Fasten the halves with quick-release clips or screws; add the lap along the split, and between the shell and its ends, with Fabrication.
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): 192 facets form a box round the pipe, its shell and its two ends, each in two halves: every edge inside a part joins exactly two facets, every open edge one (V - E + F = 0).
- Developed edges equal true 3D lengths (passed): 576 facet edges compared between the 3D surface and the flat pattern (max deviation 8.31e-13).
- Shared edges and seam closure (passed): 186 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 1.16e-9).
- Cut outlines closed and non-overlapping (passed): 6 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 insulation is taken as an even thickness all round; a jacket over insulation of uneven thickness, or over trace heating, is not modelled.
- No swage, bead or crimp is formed on the edges: the laps are flat overlaps added by Fabrication.
- The box is round; a rectangular box over a valve, or a box with a bulge for a valve stem or handwheel, is not modelled.
- Fasteners (quick-release clips, screws, rivets) and the laps where the two halves meet are not drawn; add the lap along the split with Fabrication.
- 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.
Pipe and insulation. Give the outside diameter of the pipe and the thickness of the insulation. The jacket fits over the insulation, so its diameter is the pipe and twice the insulation, taken as an inside size: leave the sizes as inside sizes, and the plate is worked out on its mid-thickness.
Flange box. The box stands on the Z axis, End A at Z = 0. Its shell is as wide inside as the flanges and the insulation round them, and as long inside as given, between its ends. Each end is a flat ring whose hole fits over the jacket of the pipe either side.
Halves. Box and cap are made in two halves split on the line through the axis, so they can be put on round a pipe already in place. Both halves are drawn; being alike, each plate is dimensioned once.
Laps. The plates are cut net. The laps, where one sheet runs over the next, come from Fabrication: a cladding module starts with a lap seam, the same overlap on the long seam of each sheet and on one side of each joint between sheets. Change it there to your specification.
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 flange box and end capOther cladding
- Elbow: The jacket over an insulated pipe bend, in mitred gores made to the pipe’s bend radius and the outside of the insulation, with laps between them.
- Tee: The jacket over an insulated tee, equal or reducing: the run with the hole for the branch, and the branch cut to the saddle.
- Reducer: The jacket over an insulated reducer, concentric or eccentric: a cone between the outsides of the insulation on the two pipes.