How many gores does a 180 degree return need?

Since the angle is twice that of a 90 degree bend, the gore count usually doubles to keep the same finish. Five to seven is the usual range.

Where is the radius measured from?

From the centre of the bend to the tube axis, as in the other segmented bends.

180° Bend flat pattern

What it is

The 180 degree segmented bend — the full return. Same construction as the segmented bend with the angle locked: the tube leaves in the direction opposite to the one it entered, around the radius you give.

Where it is used

Returns in coils, plate-built heat exchangers, ducting that must double back within a short run.

Measurements the calculation needs

H Height
D Diameter
ANG Angle
S Sections
DV Divisions
THK Thickness

Worked example

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

Height	1200 mm
Diameter	800 mm
Angle	180°
Sections	5
Divisions	16
Thickness	10 mm
The flat pattern fits a plate of	2482 × 1036 mm
Flat patterns produced	2

Frequently asked questions

How many gores does a 180 degree return need?: Since the angle is twice that of a 90 degree bend, the gore count usually doubles to keep the same finish. Five to seven is the usual range.
Where is the radius measured from?: From the centre of the bend to the tube axis, as in the other segmented bends.

180° Bend dimension drawing: the measurements the calculation asks for, marked on the part

Calculate a 180° Bend

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