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ASTM A320 L7
ASTM A320 L7 material
boltingbolting
⚡
Key Engineering Metrics
Instant specifications summary for ASTM A320 L7
Yield Strength💪
-MPa
Min specified
Tensile Strength🏋️
-MPa
Ultimate min
Carbon Eq. (CE)🧪
N/A
IIW Formula
P-No. / Group⚙️
-
ASME Sec. IX
Flange Group🛡️
N/A
ASME B16.5
MDMT Curve❄️
Refer to
ASME B31.3
General Specifications & Standard Data
ASTM A320Standard Specification
ASTM A320
Grade / Designation
L7
UNS Designation
N/A
ASME P-No. / Group No.
Unassigned
ASME B31.3 MDMT Curve
Refer to ASME B31.3 Fig 323.2.2A
Minimum Design Metal Temperature rules for impact testing exemption under ASME B31.3 paragraph 323.2.2.
Mechanical Properties
Room Temp (20°C / 68°F)Density
7850kg/m³
Min Yield
-MPa
Min Tensile
-MPa
Elastic Modulus
205GPa
Thermal Expansion
12µm/m·K
Thermal Cond.
42W/m·K
Poisson’s Ratio
0.3
Allowable Stress Data (ASME B31.3 Table A-1)
asme-bpvcAllowable Stress vs Temperature
ASME B31.3 / BPVC Section II Part D Reference Curve
Max: 172.4 MPaRange: 38° - 400°
| Temperature (°C) | Allowable Stress (MPa) | % of Room Temp Rating |
|---|---|---|
| 38 | 172.4 | 100% |
| 100 | 172.4 | 100% |
| 150 | 172.4 | 100% |
| 200 | 172.4 | 100% |
| 250 | 172.4 | 100% |
| 300 | 172.4 | 100% |
| 350 | 172.4 | 100% |
| 400 | 162.0 | 94% |
| 450 | – | – |
| 500 | – | – |
| 550 | – | – |
| 600 | – | – |
| 650 | – | – |
Chemical Composition (% Weight)
Heat & Product AnalysisC
0.38–0.48%
Mn
0.75–1%
Si
0.15–0.35%
P
≤ 0.035%
S
≤ 0.04%
Cr
0.8–1.1%
Mo
0.15–0.25%
Al
0.02–0.05%
🛡️ Service Compatibility
High Temp Pressure Flangesexcellent
High tensile strength for ASME B16.5 flanges up to 450°C (B7/2H) or 538°C (B8/8M).
Sub Zero & Cryogenic Boltinggood
A320 L7 / A194 Gr. 7 impact tested down to -101°C (-150°F); B8/B8M down to -196°C.
Corrosive Atmospheresgood
B8 (304) and B8M (316) provide excellent atmospheric & chemical corrosion resistance.
🔩 Compatible Nuts
Recommended bolt/nut pairings
🔗 Material Equivalents
Low Temperature Carbon Steel Service
⚠️ Engineering Verification Notice
Material property data provided is for preliminary engineering reference. Always verify properties against the latest ASME BPVC Section II, ASTM material specification, and Material Test Report (MTR/MTC).