Similar International Standards
EN 755-5:2017CEN (European Committee for Standardization), Europe
HighCurrent
Aluminium and aluminium alloys - Extruded rod/bar, tube and profiles - Part 5: Rectangular bars, square bars, round bars, flat bars, hexagonal bars and octagonal bars - Dimensions and form tolerances
Directly specifies dimensional and form tolerances for extruded aluminium equal leg angles.
ANSI H35.2-2017The Aluminum Association, USA
HighCurrent
American National Standard Dimensional Tolerances for Aluminum Mill Products
Provides the standard dimensional tolerances for aluminium extruded shapes, including equal leg angles, in the US market.
BS EN 755-5:2017BSI (British Standards Institution), United Kingdom
HighCurrent
Aluminium and aluminium alloys. Extruded rod/bar, tube and profiles. Square bars, dimensions and form tolerances
The British adoption of the European standard, making it the direct equivalent for the UK.
ASTM B221-21ASTM International, USA
MediumCurrent
Standard Specification for Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes
Specifies material requirements, properties, and quality assurance for extruded profiles, referencing ANSI H35.2 for tolerances.
Key Differences
≠IS 3908 uses a 5-digit numerical designation for aluminium alloys (e.g., 64430 for 6061), whereas international standards use the 4-digit system from The Aluminum Association (e.g., 6061) or prefixed versions like EN AW-6061.
≠European standard EN 755-5 specifies two classes of tolerances (Class 1 and Class 2), allowing for a choice between standard and precision tolerances. IS 3908:1986 provides a single set of 'normal' tolerances.
≠The structure of the standards differs. IS 3908 is a monolithic document covering dimensions, materials, and properties. The EN and ASTM systems are modular, with separate standards for tolerances (e.g., EN 755-5), mechanical properties (e.g., EN 755-2), and technical delivery conditions (e.g., EN 755-1).
≠IS 3908:1986 is an older standard, and its specified tolerances are generally looser than the 'standard' tolerances found in the current versions of EN 755-5 and ANSI H35.2, reflecting advancements in extrusion technology.
Key Similarities
≈All standards fundamentally cover the same product: extruded aluminium alloy equal leg angles for general engineering and structural purposes.
≈The core geometric parameters controlled by the standards are identical: leg length, thickness, angle (squareness), straightness, twist, and corner radii.
≈All standards recognize and specify requirements based on the material's temper (heat treatment condition), such as T4 or T6, which dictates the final mechanical properties of the angle.
≈The primary objective of all these standards is to provide a common technical basis for manufacturers and purchasers, ensuring product consistency, quality, and dimensional interchangeability.