The ASTM A105 Flange Specification

ASTM A105 is the standard specification for carbon steel forging flanges

ASTM A105 is a standard that applies to forged carbon steel flanges and piping components used in pressure systems for both ambient and elevated temperature service. It also encompasses valves, pipe fittings, and similar items. The maximum weight for forgings produced under this standard is 10,000 pounds (4540 kg). For larger forgings, the A266/A266M standard should be referenced instead. This specification does not apply to tube sheets or hollow cylindrical forgings intended for pressure vessel shells.

Additionally, this specification excludes raw materials such as round bars and seamless tubular products used to manufacture piping components.

The following list of standard apply to these specification:

*A266/A266M Specification for carbon steel forgings for pressure vessel components.
*A675/A675M Specification for hot-rolled, special quality and mechanical properties, carbon steel bars.
*A696 Specification for steel bars, carbon, hot-rolled or cold-finished,special quality, for pressure piping components.
*A788/A788M Specification for steel forgings, general requirements.
*A961/961M general requirements for steel flange, forging fittings, valve and parts for piping applications.

SP44 Standard for steel pipe line flange

*B16.5 Dimensional standard for steel pipe flanges and flanges fittings
*B16.9 Wrought steel butt-welding fittings
*B16.10 Face-to-face and end-to-end dimensions of ferrous valves
*B16.11 Forged steel fittings, socket weld and threaded
*B16.34 Valves connect by flanges, threaded and welding end
*B16.47 Large diameter steel flanges
*ASME boiler and pressure vessel code

*API-600 Flanged and butt-Welding-end steel gate valves
*API-602 Compact design carbon steel gate valves for refinery use

A The sum of copper, nickel, chromium, molybdenum and vanadium shall not exceed 1.00%.
B The sum of chromium and molybdenum shall not exceed 0.32%.

For definitions of other terms used in this specification, find in specification A961/A961M.

See specification A961/A961M.

If conflict between the requirements of this specification and Specification A961/A961M. Comply with this specification.

Heat treatment is generally not necessary unless the flanges are rated above Class 300, are of a special design where the design pressure or temperature is unspecified, or if the components are larger than 4″ NPS and exceed Class 300. When heat treatment is required, the applicable methods include annealing, normalizing, normalizing and tempering, or normalizing followed by quenching and tempering.

These components can be welded. Welding procedures must comply with ASME Boiler and Pressure Vessel Code Section IX.

ASTM A105 carbon steel can be forged at temperatures in the range of 2200 to 1700 F followed by quenching and tempering or normalizing.

Forged components may be cooled to temperatures below 1000°F, followed by reheating within the range of 1550°F to 1700°F. After this process, slow cooling in a furnace should be performed.

The hydrostatic test is to be performed by the forging manufacturer only when Supplementary Requirement S57 of ASTM A961 is explicitly specified.