Pipe Offset

Pipe offset

Preliminary. This is the geometry of a two-elbow offset. It needs engineering review before anyone cuts pipe. It is not a flexibility analysis. Take-out is the length you type. This page does not look up an elbow dimension.

Formulas

travel = offset / sin(angle)

run = offset / tan(angle)

offset = travel × sin(angle) = run × tan(angle)

travel = run / cos(angle)

run = travel × cos(angle)

true offset = √(roll² + set²)

cut length = travel − take-out − take-out

The angle is the fitting angle, between the run and the travel. Offset is the centre-to-centre distance between the two parallel lines. Travel is the centre-to-centre length of the angled pipe. Run is the distance along the original line between the two fittings. For a rolling offset, roll and set are perpendicular to each other and to the run. The true offset is their diagonal, and the travel and run use that true offset with the fitting angle. A blank length is the one to solve. Feet and inches are rounded to the nearest 1/16 inch. Millimetres are shown to 0.1 mm.