Fixtra

Tube & Pipe Bend Calculator

Give it the tube OD, the centerline radius (CLR), and the X-Y-Z coordinates of each bend point from your drawing — it returns the cut length, every bend angle, each arc, and the roll rotation between bends. Or use the quick single-bend check.

1Set the tube OD and CLR (one common radius for all bends).  2Type the X, Y, Z of every node point from the drawing table, in order — PT0 is the start, the last point is the end.  3Read the cut length and bend procedure. Three points make one bend; add a point for each extra bend.

Tube

Used only for the bendability check — not for length.
Leave 0 for pure geometric length. To match a shop process, enter your own validated factor — total bend arc is multiplied by it and added (e.g. 0.0164).

Coordinates — from the drawing table

XYZ

Results

Total cut length
With material stretch
Straight material
Bend material (total arc)
Number of bends
End-to-end (PT0 → last)

Bend angle is the included angle between legs (as drawings usually call it); DOB is the degree the machine bends through (180° − included). Rotate is the roll about the tube between one bend plane and the next. Springback is not applied — overbend per your own test bends. Material stretch uses the factor you enter above.

One bend

Results

Bend arc length (centerline)
Setback (tangent → intersection)
Bend deduction
Wall at outside of bend (est.)
CLR / OD ratio
OD / wall (D/t) ratio

Arc length is the developed length of the bend along the centerline. Wall-thinning and bendability are estimates — confirm with a test bend.