Reference

Unit Conversions & Tables: Precision Synchronization

In multi-national engineering, rounding errors or unit mismatches can lead to catastrophic assembly failures. Edelweis enforces a "Metric-First" policy, treating units as fixed variables to ensure absolute mathematical harmony across the Unified TDP, BOM, and CAM data.

1. The Metric-First Directive (SI Standard)

Edelweis operates on a standardized SI (International System of Units) baseline to eliminate ambiguity:

Linear Dimensions

Millimeters (mm) are the absolute standard for all Technical Drawings and CAM outputs.

Mass & Weight

Grams (g) or Kilograms (kg) are synced directly from the Material Library to the BOM.

Force & Stress

Newtons (N) and Megapascals (MPa) are mandatory for all FEA Methodology reports.

2. Global Supply Chain Conversion Tables

Measurement	SI Unit (Preferred)	Imperial Equivalent	Factor
Length	1 mm	0.03937 in	÷ 25.4 (Exact)
Pressure	1 bar	14.5038 psi	≈ 14.504
Torque	1 N⋅m	8.8507 lbf⋅in	≈ 8.851
Mass	1 kg	2.2046 lb	≈ 2.205

3. Numerical Precision & Rounding Rules

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Simulation Data: All FEA/CFD results must maintain 4-decimal place precision for mesh sensitivity stability.
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Manufacturing Drawings: Following ASME Y14.5 standards; rounding is strictly prohibited on Critical-to-Quality (CTQ) features.
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Angular Units: Decimal Degrees (e.g., 15.5°) are preferred over DMS to ensure 5-axis toolpath accuracy.

4. Material-Specific Density & Constants

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Density Sync: Defined in g/cm³ and kg/m³ to prevent calculation errors during raw material estimation.
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Thermal Expansion: Coefficients (CTE) standardized in µm/m·K for high-precision thermal probe mapping.
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Modulus Verification: Young’s Modulus recorded in GPa to provide high-fidelity safety factor predictions.

Technical Directives

Directive	Protocol
Unit Consistency Lock	All CAD files must be locked to Millimeters at the template level before modeling begins.
Dual Dimensioning	Only permitted on Technical Drawings if explicitly required by the Vendor.
Automated Conversions	All conversions in BOMs must be performed via system formulas, never manual entry.