ASTM A105 flanges

1. ASTM A105 forged carbon steel flanges.

ASTM A105 is the standard specification for carbon steel forgings for piping applications including flanges, fittings and valve parts, etc. According to ASME B16.5(Pipe Flange), this material is categorized into Group 1.1 which has the same pressure-temperature ratings as ASTM A216 Grade WCB, A515 Grade 70, A350 Grade LF2, A516 Grade 70, A350 Grade LF6 Class 1, A537 Class 1 and A350 Grade LF3. ASTM A105 flanges refer to forged carbon steel flanges for ambient and high temperature service in pressure systems.They can be manufactured to dimensional standards of ASME B16.5, ASME B16.47, MSS SP 44, API 605, BS 4504, EN1092-1 and L-005, etc. HBMetals keeps a large amount of flanges available in stock covering flange types of welding neck, slip on, socket welding, threaded, blind, slip on plate, long weld neck, orifice and lap joint, etc.

ASTM A105 flanges in various types
ASME B16.5 Flanges in A105 material(WN, SO, BL)

2. Chemical composition, mechanical properties and pressure-temperature ratings for ASTM A105 flanges.

Chemical Composition Requirements of ASTM A105

Carbon (C)0.35max
Manganese (Mn)0.60–1.05
Phosphorus (P)0.035max
Sulfur (S)0.040max
Silicon (Si)0.10–0.35
Copper (Cu)0.40max
Nickel (Ni)0.40max
Chromium (Cr)0.30max
Molybdenum (Mo)0.12max
Vanadium (V)0.08max
*The sum of copper, nickel, chromium, molybdenum and vanadium shall not exceed 1.00% while the sum of chromium and molybdenum shall not exceed 0.32%. The carbon equivalent CE = C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15 shall be no larger than 0.47 based on heat analysis.

Mechanical Properties of ASTM A105

Mechanical PropertiesRequirements
Tensile strength,min,psi [MPa]70000 [485]
Yield strength,min,psi [MPa]36000 [250]
Elongation, min, %30
*Unless otherwise specified by the customer, heat treatment is not a mandatory requirement for 150LB and 300LB A105 flanges. However, flanges above Class 300 (Class 400, 600, 900, 1500, 2500) or custom-design special flanges shall be furnished with one of the following heat treatment: 1) annealing, 2) normalizing, 3) normalizing and tempering, 4) quenching and tempering.

Pressure-Temperature Ratings for ASTM A105 flanges

Temp. °CWorking Pressure by Classes, bar
-29 ~ 3819.651.168.1102.1153.2255.3425.5
*ASTM A105 flanges are not recommended for prolonged use above 425°C since upon prolonged exposure to temperature above 425°C, the carbide phase of steel may be converted to graphite causing brittleness problems.

If you have any inquiry, please feel free to contact our Metals-Piping Division for a quote:
Email: | Website:

Leave a Reply

Your email address will not be published. Required fields are marked *