Pre-nesting Manufacturing Plates - Intergraph Smart 3D - Help

Intergraph Smart 3D Structural Manufacturing

PPMProductFamily
3D Design and Visualization
PPMProduct
Intergraph Smart 3D
PPMCategory
Help
Version_S3D
11.x(2016)

If the manufacturing type is set to Pre-nesting, you can select either a light or detailed part for manufacturing. The software uses the same manufacturing process for both light and detailed parts with the following exceptions:

Light Parts

In production nesting, the software uses the detailed plate part to retrieve the neutral surface and the contour information. When you detail a part, Smart 3D trims that part to the bounding structure. This process causes the neutral surface and the contours to be trimmed to the bounding elements.

With pre-nesting, the software uses the light part to get the neutral surface and its contours. In this case, Smart 3D does not trim the contours to the bounding elements.

1. Molded Surface
2. Thickness Direction
3. Neutral Surface
4. Thickness Direction

Neutral surface from light part

1. Detailed Part
2. Neutral Surface
3. Thickness Direction

Neutral surface from detailed part

1. Neutral Surface
2. Thickness Direction
3. Molded Surface
4. Thickness Direction

Neutral surface from light part

1. Neutral Surface
2. Thickness Direction
3. Molded Surface
4. Thickness Direction

Neutral surface from detailed part

Logical Connections

Production nesting uses physical connections to retrieve the bevel information from the model and carry that information to the edge. With pre-nesting, the software stores the logical connections in the manufacturing bevel objects.

Bevel Offset Correction Calculation

In production nesting, the software calculates the attachment angle directly from the plate upside surface and the surface that touches the bounding structure element. Smart 3D calculates the bevel offset correction from this attachment angle, the physical connection bevel properties, and the plate thickness values.

In pre-nesting, the software always calculates the bevel offset correction for every contour edge to the long point using the following algorithm.

  1. Get the edge direction and plate upside surface normal.

  2. Calculate the cross product of those vectors to get the material direction.

  3. Get the logical connection from the bevel and the connected ports and connected structural plate and profile parts.

  4. Get all of the ports of the bounding plate or profile part.

  5. For each face port in the port collection:

    1. Project the input point onto the bounding surface in the material direction.

      • For plates, the software projects the point onto the base and offset surfaces.

      • For profiles, the software projects onto all lateral faces, except the base and offset end caps.

    2. Determine whether the point is projected towards the material direction or away from the material direction.

      • If the point is projected towards the material direction, the software takes the farthest bounding point and calculates the negative bevel offset correction value.

      • If the point is projected away from the material direction, the software takes the closest bounding point and calculates the positive bevel offset correction value.

    3. If the software finds a point at which the minimum or maximum bevel correction is calculated, Smart 3D stores that point for further processing. The software also stores the bevel correction value.

  6. Calculate the attachment angle from the plate upside surface and the touching surface of the bounding structure elements.

  7. Adjust the bevel correction value to the long point based on the attachment angle and plate thickness values.

Varying Bevel Calculation

If a deck plate is bounded by a shell plate, the mounting angle changes along the plate edge length based on the hull curvature. In such a case, the software automatically applies the varying bevel on the manufacturing part of the light part. The software splits the edge with the associated logical connection at a few intermediate positions and calculates the attachment at the midpoint of each segment. If the change of attachment angle varies more than the user-specified value (typically 3 degrees per meter), then the software splits the edge, and each segment has its own attachment angle. This behavior is similar to detailing the part and its physical connections.

Feature Cuts

In production nesting, the software applies feature cuts after unfolding the plate parts. In the pre-nesting solution, the software does not apply feature cuts.

Margins and Shrinkages

In both production nesting and pre-nesting, the software applies margins and shrinkages on the plate part. There are no changes in this functionality.