ASTM A105 Flanges
ASTM A105 / SA 105 Flanges
ASTM A105 is a specification for carbon steel forged components including flanges used primarily in high-temperature and high-pressure applications. These flanges are widely used in oil & gas, petrochemical, power generation, marine, and industrial systems due to their excellent strength, machinability, and weldability.
ASTM A105 flanges are suitable for ambient- and higher-temperature service in pressure systems. They are among the most demanded flanges for industrial piping systems.
ASTM A105 Flange Specifications
| Standard | Details |
|---|---|
| Material Grade | ASTM A105 |
| Manufacturing Method | Forged Carbon Steel |
| Standard | ASME B16.5, B16.47, MSS-SP-44, BS, DIN |
| Pressure Class | 150# – 2500#, PN6 – PN400 |
| Sizes | ½” to 48″ (DN15 to DN1200) |
| Face Type | RF / FF / RTJ |
| Application | High-temperature, high-pressure piping systems |
ASTM A105 Flange Equivalent Grades
| ASTM | ASME | UNS | WNR |
|---|---|---|---|
| A105 | SA105 | K03504 | 1.0460 |
Available Sizes
NPS: ½” to 48″
DN: 15 to 1200
Pressure Rating: Class 150 – Class 2500 / PN6 – PN400
ASTM A105 Flange Chemical Composition
| Element | % |
|---|---|
| Carbon (C) | 0.35 max |
| Manganese (Mn) | 0.60 – 1.05 |
| Phosphorus (P) | 0.035 max |
| Sulfur (S) | 0.040 max |
| Silicon (Si) | 0.10 – 0.35 |
| Copper (Cu) | 0.40 max |
| Nickel (Ni) | 0.40 max |
| Chromium (Cr) | 0.30 max |
| Molybdenum (Mo) | 0.12 max |
| Vanadium (V) | 0.08 max |
ASTM A105 Flange Mechanical Properties
| Property | Value |
|---|---|
| Tensile Strength | 485 MPa min |
| Yield Strength | 250 MPa min |
| Elongation | 22% min |
| Hardness | 187 HB max |
ASTM A105 Flange Physical Properties
| Property | Value |
|---|---|
| Density | 7.85 g/cm³ |
| Melting Point | ~1425 – 1540°C |
| Thermal Conductivity | 60.5 W/m-K |
| Modulus of Elasticity | 190 – 210 GPa |
Types of ASTM A105 Flanges
Corrosion Resistance
Atmospheric corrosion
Mild acidic & alkaline environments
General industrial and marine conditions
Heat Resistance
Suitable for temperatures up to ~500°C
Maintains strong tensile & yield properties at elevated temperatures
Heat Treatment
Heat treatment is applied based on service requirements:
Normalizing
Quenching & Tempering (if required)
Stress Relieving
Welding
Excellent weldability
Suitable welding methods: SMAW, GTAW, GMAW, SAW
Pre-heating recommended for thick sections
Post-weld heat treatment (PWHT) optional based on service requirement
Fabrication
Easy to machine, cut, drill & form
Good forging and shaping capability
Suitable for threading & flanging operations
Applications
Oil & Gas Pipelines
Petrochemical & Refinery Plants
Power Plants & Steam Services
Shipbuilding & Marine Engineering
Chemical Processing Systems
High-temperature boiler & pressure vessels
Heat Exchangers, Pumps & Valves