materials - Material Properties
The materials module provides temperature-dependent material properties for
pressure vessel calculations, primarily focused on structural steels used in
fire scenarios.
Material property database for pressure vessel calculations.
This module provides temperature-dependent material properties for common pressure vessel materials including: - Stainless steels (SS316, Duplex, Super Duplex) - Carbon steels (low temperature grade) - Vessel wall materials (steel, aluminum, composites)
Properties available: - Heat capacity (Cp) as function of temperature [J/(kg·K)] - Ultimate tensile strength (UTS) as function of temperature [MPa] - Allowable tensile stress (ATS) as function of temperature [MPa] - von Mises equivalent stress calculations
Data sources: - Scandpower Risk Management AS guidelines for fire scenarios - EN standards for structural steel properties - Literature values for composite materials
All temperature data are stored in Kelvin [K]. Property values are interpolated using numpy.interp() for intermediate temperatures.
- hyddown.materials.von_mises(p, d, wt, sigma_a=30000000.0)[source]
von Mises stress calculated according to: Hekkelstrand, B.; Skulstad, P. Guidelines for the Protection of Pressurised Systems Exposed to Fire; Scandpower Risk Management AS: Kjeller, Norway, 2004.
As also applied in: Andreasen, A.; Borroni, F.; Zan Nieto, M.; Stegelmann, C.; P. Nielsen, R. On the Adequacy of API 521 Relief-Valve Sizing Method for Gas-Filled Pressure Vessels Exposed to Fire. Safety 2018, 4, 11. https://doi.org/10.3390/safety4010011
- hyddown.materials.ATS(temperature, material, k_s=0.85, k_y=1)[source]
Calculation of Allowable Tensile Strength according to: Hekkelstrand, B.; Skulstad, P. Guidelines for the Protection of Pressurised Systems Exposed to Fire; Scandpower Risk Management AS: Kjeller, Norway, 2004.
- Parameters:
temperature (float) – Temperature (K)
material (string) – Material type: 235LT, 360LT (ASTM A-333/A-671), 2205 (SA-790/ASTM A-790), 316 (ASTM A-320, ASME A-358), 6Mo (ASTM B-677)
k_s (float) – General safety factor. For typical materials 0.85 is used. If “guaranteed” minimum values a factor 1.0 can be used.
k_y (float) – Additional factor used for materials with missing or uncertain material data. Normally 1.0.
- Returns:
ATS – Allowable Tensile Strength (Pa)
- Return type:
- hyddown.materials.UTS(temperature, material)[source]
Tabulation look-up / interpolation to retrieve the Ultimate Tensile Strength as a function of temperature for various typical materials according to:
Hekkelstrand, B.; Skulstad, P. Guidelines for the Protection of Pressurised Systems Exposed to Fire; Scandpower Risk Management AS: Kjeller, Norway, 2004.
- hyddown.materials.steel_Cp(temperature, material)[source]
Tabulation look-up / interpolation to retrieve the heat capacity as a function of temperature for various typical materials according to:
Hekkelstrand, B.; Skulstad, P. Guidelines for the Protection of Pressurised Systems Exposed to Fire; Scandpower Risk Management AS: Kjeller, Norway, 2004.