Casting - Sand Enhancements

aPriori 2023 R1 provides these enhancements for the Sand Casting process group:

Updated Costs and Improved Usability for Sand and Sand Additive Data

The unit cost data for both Sand and Sand Additives were updated to better reflect market pricing and the data was moved from a lookup table to Digital Factory toolshops to facilitate your Regional Data Library updates.

Market prices for the sand and the various types of sand additives have recently increased. To ensure that the cost estimates for sand casting parts reflect the price changes, aPriori 2023 R1 includes updated cost data for sand and for sand additives.

Additionally, To make it easier to update the costs when you apply aPriori Regional Data Libraries (RDL) updates, several sets of cost data have been moved from lookup tables to Digital Factory toolshops. The relocated data includes sand costs, which were previously stored in the tblSand lookup table and metal sand additive costs, which were previously stored in the tblMetalAdditives lookup table.

While the costs for sand additives in the tblSandAdditives lookup table were updated, the data was not moved to Digital Factory toolshops, because doing so would create a large amount of data duplication.

Due to the updated sand and sand additive costs, the Fully Burdened Cost of sand-cast parts will increase relative to the previous release. The average increase In a set of test parts was 2%.

Updated Costs and Solvent-Based Refactory Coating Options for Refractory Coat Processes

To increase the accuracy of both refractory coating cost estimates and sustainability (carbon-equivalent) estimates, the aPriori Casting-Sand process group provides additional refractory coating types and updated costs.

Previously, aPriori assumed that only water-based refractory coating types were used for sand-casting. Now aPriori allows you to choose between water-based coatings and solvent-based coatings for both the Core Refractory Coat and the Mold Refractory Coat processes in the Casting-Sand process group.

The default coating type for these refactory coating process is controlled by the new cost model variable defaultRefractoryBaseLiquid (set to Water-Based by default). To change the coating on a per-part basis, use the new process setup option Refractory Base Liquid.

To reflect current market costs, water-based refractory coating costs were reduced from $2.48/L to $1.00/L. Solvent-Based refractory coating cost data was added in accordance with the current market value of $6.39/L. These costs are specified in Toolshops for the Core Refractory Coat and Mold Refractory Coat processes.

As a result of the reduction in water-based refractory coating costs, for default configurations, sand cast part costs will decrease compared to the previous release. In a set of test parts, costs were 4.3% lower on average.

Read Draw Direction from CAD File

aPriori 2023 R1 provides a new capability to use a CAD-defined draw direction to reduce analysis times and support highly-automated aPriori workflows.

Historically, aPriori has relied mainly on its powerful, proprietary algorithm for analyzing the geometry of molded parts (including plastic injection moldings, castings, and forgings) and determining the draw direction (mold-opening direction). This algorithm evaluates many candidate directions and selects one based on many criteria including the amount of undercut volume, alignment with various features on the part, flatness of the resulting parting line and required mold-opening height. In some cases the draw direction ultimately selected by aPriori, while reasonable, is different than the intended as-designed draw direction. Therefore, aPriori has also allowed you to specify the desired Draw Direction interactively. To do so, you had to inspect and, as needed, edit the draw direction and then recost the component using newly extracted GCDs.

In this release, instead of using the proprietary algorithm, you can configure aPriori to read and use designated datum references in the CAD file as the specified Draw Direction. Doing so eliminates the need to manually review and sometimes update the chosen draw direction, and also results in faster GCD extraction. This capability is available in aPriori Professional (for both on-premise and cloud deployments) and Cost Insight Design, (for cloud deployments), and is particularly useful for supporting high-volume lights-out workflows, which leverage aPriori Generate.

These process groups support reading Draw Direction from NX, CATIA, SolidWorks and Creo CAD models (including both Creo Direct Integration and CAD-I/cloud environments):

  • Plastic Molding

  • Casting Die

  • Casting Investment

  • Casting Sand

  • Forging

  • Powder Metal

To leverage this capability, your organization must:

  1. Adopt some company-standard ways of designating draw direction in your CAD models.

  2. Configure the CAD Property Mapping File to identify the standard draw direction references.

    An aPriori System Administrator can perform this step.

If a newly costed CAD model contains your company-standard draw direction references, aPriori will use them. Otherwise, it will fall back to using the proprietary algorithm for determining draw direction.

Draw direction references are defined for the entire aPriori deployment. aPriori Professional provides flexibility in how draw direction may be designated, to support different naming conventions, languages, and modeling approaches used within different divisions of a company or standards which have evolved over time.

Here is a summary of the rules for designating draw directions. For complete details, please refer to the Draw Direction Mapping section in version 2023 R1 of the aPriori Professional System Administration Guide.

In general, aPriori supports specifying draw directions using these types of CAD entities:

  • An axis of a coordinate system with a custom name (for example, the Z-axis of the coordinate system named "Draw_Direction")

  • A datum axis with a given name

  • A datum plane with a given name (draw direction is perpendicular to the plane)

aPriori allows you to define multiple possible draw direction references in the CAD Property Mapping File as well as a priority order. When analyzing a part file, aPriori uses the highest-priority reference that exists in that part file as the draw direction. To capture when the draw direction is read from the CAD file, these new properties are available for the Parting Line GCD:

  • Mapped Draw Direction Name displays the full name of the CAD datum object that defines Draw Direction. If this field is empty, then draw direction was not read from the CAD model and the historical algorithm was used.

  • Mapped Draw Direction Type displays the type of the CAD datum object that defines Draw Direction. Possible values are Coordinate System, Axis, or Plane.

  • Mapped Draw Direction Axis is used only if Mapped Draw Direction Type is equal to Coordinate system and if so displays the axis of that coordinate system used to define draw (X, Y, or Z) otherwise no value is displayed in this field.