Details: Changes to Baselines that DO NOT affect Customer VPEs
The following changes are available in the aPriori Baseline VPEs only. If you wish to take advantage of these new capabilities, the VPE needs to be upgraded to the most recent Cost Model version. Please contact your VPE Admin or aPriori Account Manager to plan work.
• New Material Properties: This release introduces three new material properties:
o Density of Melt
o Specific Heat of Melt
o Thermal Conductivity of Melt
During costing, these new fields are now used to compute material thermal diffusivity, which in turn is an input to cool time calculations for Extrusion Blow Mold. In previous releases, the cool time calculations used the material property Thermal Diffusivity, taken directly from the material table rather than computed.
For some materials, the computed value for thermal diffusivity differs somewhat from the material table field value used in previous releases. As a result, the calculated cool time for a part might change in this release, compared to previous releases. The direction and magnitude of the change varies across materials and parts. See Updated Material Property Values, below.
Note that, in this release, if the new properties are not populated for the current material, the cool time calculations use the material property Thermal Diffusivity (which is now hidden by default in material property displays).
• Updated Material Property Values: some property values for some materials have been updated to increase accuracy. Properties that have been updated for some materials include:
o Density
o Eject Deflection Temp
o Melting Temp
o Mold Temp
o Injection Pressure Max
o Injection Pressure Min
For materials suitable for blow molding, non-negligible cost changes might occur. For a 1.5mm-thick part and a production volume of 50,000, we observed cost increases of 0%-10% for some materials and decreases of 0%-5% for other materials. For blow molding ABS materials, the cost increase was around 20%, compared to the previous release.
• Tooling Cost and Tool Life: In previous releases, tooling cost calculations assumed that a single tool lasts long enough to produce the production volume specified in any scenario. In this release, the cost model estimates the number of parts that can be produced with a given tool before it wears to the point that it needs to be replaced. Based on that estimate, the cost model determines the number of tools required to manufacture the specified production volume, and accounts for that number of tools in total hard tooling cost.
Tool life is accounted for in the tooling cost calculations for the following processes:
o Extrusion Blow Mold
o Rotational Mold
Tool-life estimation is based on part material, tool material, and tool coating type. For a given costing, either the formula Dependencies or Investment tab displays the number of tools assumed by tooling cost calculations.
With default production volumes (5,500 parts annually for 5 years), hard tooling cost is not affected by this change, as only one tool is required. With production volumes that require multiple tools, hard tooling cost increases compared to previous releases.
• Improved Estimation of Tool Coating and Tool Heat Treatment Costs: this release includes improved data for tool material density, tool material unit cost, and tool coating unit cost. Change to hard tooling cost is expected to be negligible.