Pipe developments and 3D preview

Create flat cutting patterns and inspect the nominal assembled surface. Dimensions describe the chosen geometry; manufacturing allowances must be considered separately.

Which tool should I choose from Complex shapes > Pipes?

Use Cylinder for a straight rolled cylinder, Elbow for a segmented bend, S bend for an offset connection and U bend for a return connection. Pipe intersection creates the joining outlines for a branch meeting a trunk pipe.

Enter the dimensions, press Preview and inspect both the flat pattern and 3D tabs before inserting. The result placed in the drawing is the 2D geometry. You can then choose its insertion point with snaps or coordinates and create machining operations just as for other generated shapes.

How do diameter, bend radius and segment count affect a bend?

Diameter defines the cylinder size. The bend radius field describes the inside turning radius; do not confuse it with an outside or centerline radius from another drawing. The first and last straight lengths extend the end sections. More segments make a segmented bend approximate the intended turn more closely, but add seams.

Elbow accepts 2 to 100 segments. S and U bends use an odd count from 3 to 99; follow the angle conditions shown for the selected form. After changing a count, angle or length, refresh Preview and check that the end directions and spacing match the intended assembly.

How should I set seam margins and curve tolerance?

A seam or margin allowance adds material to the flat layout where provided by the form. For a cylinder, the developed width is the circumference plus the margins. Curve tolerance controls the approximation of curved outlines: a smaller value gives finer detail but more segments.

The tools show nominal geometry; they do not automatically calculate neutral-axis corrections, springback, weld preparation or wall-thickness allowances. Set dimensions and allowances according to the fabrication method. The 3D view represents the nominal assembled surface, so a seam margin in the flat layout is not a visible thick overlap in that preview.

Can I place bend segments closer or use Common cut?

The flat bend layout packs matching segment boundaries closely, with a default gap of 1 mm. Adjust the gap to suit cutting width, entry paths and handling. Common cut is available for Elbow, S and U bends and shares matching boundaries so those lines are cut only once.

With Create operations enabled, the shared dividers are cut before the outer boundary in one centered operation. Common cut removes material from both adjacent pieces and does not independently compensate each finished edge. Use separate closed parts with adequate spacing when both edges require their own dimensional compensation. Do not add a second cut over the shared lines.

How do I inspect the assembled result in 3D?

Select the 3D preview tab in the pipe form. Drag with the left mouse button to rotate, use the mouse wheel to zoom and use its fit control to bring the complete assembly back into view. Rotate far enough to inspect both the joining side and the rear side.

After editing parameters, press Preview again; both previews update while the chosen tab remains selected. The view helps you understand orientation, bend shape and intersections. It is not a thick-walled solid or a manufacturing simulation, and the geometry inserted into the drawing remains the flat development.

What should I check for a pipe intersection?

Enter the trunk diameter and length, the branch diameter and length, the intersection angle and the seam position. The branch diameter must not exceed the trunk diameter. The branch length is measured from the intersection of the axes; allow for that when comparing it with an exposed length on a workshop drawing.

Choose whether to create both developments, only the trunk or only the branch. Rotate the seam to place the opening sensibly on the flat pattern. If an opening crosses the seam, it can appear as matching edge cutouts rather than one central hole. Check both 2D and 3D before cutting.