Carbon Steel Flanged Fittings
ASTM A105 20'' 150# ASME B16.5 B16.9 B16.11 B16.34 CARBON STEEL FLANGE
Scope
ASTM A105 (also known as ASME SA 105) covers seamless forged carbon steel piping components for use in pressure systems at ambient and high-temperature service.
Flanges, fittings, valves and various other parts ordered to customer dimension or to industry standards such as MSS, ASME and API specification are included in the scope.
Forgings to this specification are limited to 10,000 lbs.
Welding
These components can be welded. Welding procedures must comply with ASME Boiler and Pressure Vessel Code Section IX.
Heat Treatment
Heat treatment is not a mandatory requirement except for flanges above Class 300, flanges of special design where the design pressure or design temperature are not known and for items over 4” NPS and above Class 300. When heat treatment is required, annealing, normalizing, normalize and temper, normalize and quench and tempering shall be the applied methods.
Forging
This alloy is forged at between 1,700 degrees Fahrenheit and 2,200 degrees Fahrenheit, followed by quenching and tempering.
Annealing
Forged parts are allowed to cool to below 1,000 degrees Fahrenheit before reheating to between 1,550 degrees Fahrenheit and 1,700 degrees Fahrenheit. Slow furnace cooling follows.
Chemical Composition
| Element | Composition %, Note C |
| Carbon | .35 max |
| Manganese | .60-1.05 |
| Phosphorus | .035 max |
| Sulfur | .040 max |
| Silicon | .10-35 |
| Copper | .40 max, note A |
| Nickel | .40 max, note A |
| Chromium | .30 max, note A,B |
| Molybdenum | .12 max, note A,B |
| Vanadium | .08 max, note A |
Note A – The sum of copper, nickel, chromium, molybdenum and vanadium shall not exceed 1.00%
Note B – The sum of chromium and molybdenum shall not exceed .32%
Note C – for each reduction of 0.01% below the specified carbon maximum (.35%), an increase of .06% manganese above the specified maximum (1.05%) will be permitted up to a maximum of 1.65%
Mechanical Properties
| Tensile | 70 ksi, min |
| Yield | 36 ksi, min |
| Elongation in 2in, Basic minimum for wall 5/16″ and over, strip test | 0.3 |
| Hardness | 187 HBW max |
Hydrostatic Test
Hydrostatic Test shall be conducted by the forging manufacture only when Supplemental S57 of ASTM A961 is specified.
Reference Documents
A266/A266M Specification for Carbon Steel Forgings for Pressure Vessel Components
A675/A675M Specification for Steel Bars, Carbon, Hot-Wrought, Special Quality, Mechanical Properties
A696 Specification for Steel Bars, Carbon, Hot-Wrought or Cold-Finished, Special Quality, for Pressure Piping Components
A788/A788M Specification for Steel Forgings, General Requirements
A961/A961M Specification for Common Requirements for Steel Flanges, Forged Fittings, Valves, and Parts for Piping Applications
MSS Standard – SP 44 Standard for Steel Pipe Line Flanges
B16.5 Dimensional Standards for Steel Pipe Flanges and Flanged Fittings
B16.9 Wrought Steel Buttwelding Fittings
B16.11 Forged Steel Fittings, Socket Weld, and Threaded
B16.34 Valves-Flanged, Threaded and Welding End
