Cone with Parallel-Axis Nozzle Hole flat pattern

What it is

The cone with the upright nozzle's hole already marked — the mate of the parallel-axis nozzle. Marking a hole on a cone by hand is far worse than on a cylinder, because the surface does not open into a rectangle and no tape will do.

Where it is used

The other half of the upright-nozzle job — hoppers, silos, cyclones, conical tank roofs.

Measurements the calculation needs

• D1 Diameter 1
• D2 Diameter 2
• H Height
• D Diameter
• V Outlet offset
• DV Divisions
• THK Thickness

Worked example

The values the form comes pre-filled with, run through the tool itself:

Diameter 1	400 mm
Diameter 2	3000 mm
Height	500 mm
Diameter	300 mm
Outlet offset	1200 mm
Divisions	32
Thickness	6 mm
The flat pattern fits a plate of	3208 × 3173 mm

Frequently asked questions

Why do I need this part and not just the nozzle?

Because the hole on the cone is neither a circle nor an ellipse on the flat pattern. It comes from the same intersection as the nozzle, mapped into the sector, and there is no way to mark it without the drawing.

Is the hole worked out the same way as the nozzle's mouth?

It is the same calculation, in the same place in the code. Both parts ask Base::BranchHole where one meets the other, and the spec checks it point by point — if they disagreed the hole would not match the mouth and no pattern would save it.

Where does the cone's seam go?

Diametrically opposite the hole. A longitudinal weld does not run through a cut-out.

Why is the hole larger than the nozzle's diameter?

Because the nozzle meets the cone obliquely, and the shallower the cone the more oblique the meeting. The hole is the cylinder projected onto the sloping surface, and it stretches along the slope.