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About the bolt circle (pcd) calculator
Hole centres for any number of holes on a pitch circle diameter (PCD), ready to check a flange or base plate drawing.
How it works
Each hole sits at x = (PCD ÷ 2) × cos(angle), y = (PCD ÷ 2) × sin(angle), with the holes spaced 360° ÷ n apart from the start angle.
Questions
Do you cut standard flanges?
Yes. The shape library has EN 1092-1, ASME B16.5 and BS 10 flanges with the correct PCD and holes.