📖 Frequently Asked Questions

These are the 3 basic trigonometry functions, based on a right triangle:

Mnemonic: SOH-CAH-TOA

• Sin = Opposite / Hypotenuse
• Cos = Adjacent / Hypotenuse
• Tan = Opposite / Adjacent

In pipe fitting: Used to calculate heights, lengths, and cut angles.

If you know two sides of a right triangle, you can find the angle with inverse functions:

Concrete example:

Simple offset with H = 100 mm and Run = 150 mm:

Two ways to measure angles:

• Degrees: full circle = 360°
• Radians: full circle = 2π ≈ 6.28

Conversion:

In practice:

• In the field → degrees (more intuitive)
• In formulas/code → often radians

Common angles: 90° = π/2 | 45° = π/4 | 30° = π/6

A generator line is a vertical line on the pipe surface used as a reference for layout.

• We divide the circumference into equal parts (often 12)
• Each division = a numbered generator (0, 1, 2... 11)
• We calculate the cut height at each generator
• We connect the points = cutting curve

More generators = more precise layout.

A flat pattern is the pipe "unrolled" flat. It gives you a cutting template.

• The circumference becomes a straight line
• X = position on circumference = R × θ
• Y = cut height at that point

Usage:

1. Print the development at 1:1 scale
2. Wrap around the pipe
3. Trace the curve
4. Cut!

A branch = a small pipe entering a larger one. The cut curve looks like a saddle (fish mouth).

Formula (90° perpendicular branch):

Where:

• R₁ = radius of the header pipe
• R₂ = radius of the branch pipe
• θ = generator angle (0° to 360°)

Steps:

1. Calculate z for each generator
2. Mark the heights on the pipe
3. Connect the points
4. Cut!

A Rolled Offset is a 3D offset with:

• H = vertical height
• DEP = lateral offset

Using 45° elbows, the assembly can be done flat on the workbench — that's the main advantage!

Our calculator gives you the sleeve length and the rotation angle to apply.

Simple Offset (2D):

• Offset in one plane
• 2 elbows, 1 sleeve
• To shift a line by a few inches

S-Offset (beam clearance):

• Double offset to clear an obstacle
• 4 elbows, 3 sleeves
• Goes up, across, and back down

Yes. The formulas are based on:

• Triouleyre methods (reference in pipe layout)
• ASME and EN standards
• 25 years of field experience

Results have been verified on real production cases.

Yes, 100% free.

• No registration
• No usage limits
• No "premium" version

Personal use, professional use, or training — everything is free.