Pipe Offset Calculator (Travel, Run and Multiplier for 45° and 30° Bends)
The length of the diagonal piece between two bends that moves a pipe or conduit sideways by a given offset, with the run it uses, the take-up and the multiplier — drawn to scale.
Results
The dashed line marks the value you entered.
What this tool does
To jog a pipe or conduit sideways, two equal bends are joined by a diagonal piece. Its length (the travel) is the offset divided by sin α, so the multiplier is 1.414 for 45°, 2 for 30°, 2.613 for 22.5° and 5.76 for 10° — a shallower bend gives a longer, gentler offset. If the pipe also has to move sideways in the other plane (a rolling offset), first combine the two shifts into the true offset, √(set² + roll²), and use that. Measure the distance between marks centre to centre of the bends, and allow for the take-up when cutting the straight lengths.
Formula
true offset = √(set² + roll²) · travel = true offset ÷ sin α · run = true offset ÷ tan α · take-up = true offset × tan(α/2)
Variables
| Symbol | Meaning | Unit |
|---|---|---|
h | Offset (centre to centre, how far the pipe must move over) | mm |
rl | Roll (sideways shift, for a rolling offset; 0 if flat) | mm |
al | Angle of the fittings | ° |
TR | Travel (centre to centre of the two bends, along the diagonal) | mm |
TO | True offset | mm |
RU | Run (length it uses up along the main line) | mm |
SH | Take-up (length the offset saves along the main line) | mm |
MU | Multiplier (travel ÷ true offset) | — |
Worked example
- Offset (centre to centre, how far the pipe must move over)300 mm
- Roll (sideways shift, for a rolling offset; 0 if flat)0 mm
- Angle of the fittings45 °
- Travel (centre to centre of the two bends, along the diagonal)424.3 mm
- True offset300.0 mm
- Run (length it uses up along the main line)300.0 mm
- Take-up (length the offset saves along the main line)124.3 mm
- Multiplier (travel ÷ true offset)1.4142
Limitations
- Mixing units is the most common source of error. Convert every input to the units shown next to each field before calculating.
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.