Rolling Offset
True offset, travel, and run advance for a pipe or conduit rolling offset.
Example
You enter
- Vertical rise (in) 12
- Horizontal roll / run-over (in) 9
- Fitting angle (deg) 45
You get
- True offset (in) 15
- Travel / diagonal (in) 21.213
Checked against published worked examples from: NCCER pipefitting / standard fitter's references (by name).
Details, formula, and sources
Formula or tableTrue offset = sqrt(rise^2 + roll^2) (Pythagoras); travel = true offset * cosecant(angle) = true offset / sin(angle); run advance = true offset / tan(angle); multiplier = 1 / sin(angle).
Source and editionFirst-principles rolling-offset trigonometry used in pipe fitting and conduit work (the Pythagorean true-offset and the cosecant travel multiplier); public, as taught in NCCER pipefitting and the standard fitter's references, by name.
Free accessPublic first-principles trig. Fitting make-up / take-out is product-specific and user-supplied.
What governsEstimate. AHJ and licensed professional govern.
API field namesrise_in, roll_in, angle_deg, true_offset_in, travel_in
- Fitting make-up product-specific, user-supplied; the multiplier is the center-to-center geometry onlyfitting reference