This standard defines the required dimensions, sectional characteristics, material criteria, and marking protocols for aluminium equal leg angles predominantly utilized in structural engineering. It is intended for producers, suppliers, and design engineers engaged in fabricating lightweight, corrosion-resistant aluminium angle sections common in infrastructure, defense, and mountainous region constructions. The standard guarantees uniform quality and compatibility of aluminium equal leg angles manufactured in India.
Overview
This standard defines the required dimensions, sectional characteristics, material criteria, and marking protocols for aluminium equal leg angles predominantly utilized in structural engineering. It is intended for producers, suppliers, and design engineers engaged in fabricating lightweight, corrosion-resistant aluminium angle sections common in infrastructure, defense, and mountainous region constructions. The standard guarantees uniform quality and compatibility of aluminium equal leg angles manufactured in India.
Audience
Contents
Structure
This section outlines the scope of the standard, detailing the dimensional limits, sectional characteristics, and mass per unit length of aluminium equal leg angles. Key parameters provided include designation sizes (e.g., 25x25x3 mm), mass in kg per meter, cross-sectional area in cm², root radius in mm, centroid coordinates, moments of inertia, radii of gyration, and section moduli. Symbols and rounding conventions per IS 2-1960 are also described to ensure precise engineering calculations.
This part defines important symbols and terms used in the standard, such as sectional area (a), mass per unit length (M), moments of inertia about various axes (Ix, Iy, Iu, Iv), distances to extreme fibers (ex, ty), section moduli (Zx, Zy), and radii of gyration (rx, ry, ru, rv). It also specifies the density of aluminium (2.7 gm/cm³) used for mass calculations and presents relevant formulas for radius of gyration and section modulus.
This section elaborates on the symbols introduced earlier, including their meanings and application in formulas. It provides mathematical expressions for calculating radius of gyration and section modulus. A summarized version of Table 1 is included, showing designations alongside properties such as mass, area, root radius, centroid location, moments of inertia, radii of gyration, and section modulus values for various aluminium equal leg angle sizes.
This portion details the material characteristics required for aluminium equal leg angles, including the standard density value of 2.7 gm/cm³. It outlines parameters like mass per meter, sectional area, root radius, centroid coordinates, moments of inertia, radii of gyration, and section modulus. The section also includes letter symbol definitions and an example illustrating these properties for a typical ALE 80x80x6 profile.
This chapter presents detailed dimensions and sectional characteristics of aluminium equal leg angles from the standard's Table 1. It covers parameters such as sectional area, mass per unit length, root radius, centroid coordinates, moments of inertia about principal and centroidal axes, radii of gyration, and section moduli. An example with values for ALE 80x80x6 is provided along with formulas used in structural design.
Describing the critical material requirements, this section reiterates aluminium density and elaborates on the designation system for equal leg angles. It lists parameters like mass, sectional area, root radius, centroidal coordinates, moments of inertia, radii of gyration, and section modulus. Symbol definitions are restated and an example table for ALE 80x80x6 is presented to clarify typical values.
This section specifies packaging methods which include securely bundling aluminium equal leg angles and wrapping them in bituminized hessian cloth or wooden containers. Alternative packaging arrangements may be agreed upon between supplier and purchaser. The bundle weight is subject to mutual agreement. Marking provisions allow for the optional use of the ISI Certification Mark to denote compliance, with emphasis on quality assurance and regulatory adherence.
Focusing on marking requirements per Clause 8.2, this part highlights that aluminium equal leg angles can bear the ISI certification mark, which guarantees conformity with the standard under ISI supervision. Marking includes manufacturer identification, product designation, optional ISI mark, and other details as per licensing conditions. A sample data table illustrates typical marking-related information for various sizes.
This final section outlines the inspection and quality control framework for aluminium equal leg angles, emphasizing the role of ISI certification in ensuring compliance. Continuous inspection and testing are performed under ISI oversight. The section also reiterates important symbols, units, and density values used for conformity assessment and presents a flowchart illustrating the certification process.
Frequently Asked
The standard itself does not explicitly specify particular aluminium alloys or tempers within the provided clauses. However, commonly used alloys in practice include 6061 and 6063 series, with typical tempers such as T6 (solution heat-treated and artificially aged) and T5 (cooled from elevated temperature shaping and artificially aged). Marking requirements mandate that each bundle indicate designation, alloy, temper, manufacturer’s name, and lot identification. For precise alloy and temper specifications, reference to related standards like IS 737 or manufacturer documentation is recommended.
Standard dimensions such as leg length, thickness, and mass per unit length are tabulated in Table 1 of the standard. For example, leg lengths of 25 mm, 40 mm, and 50 mm with corresponding thicknesses of 3 mm, 4 mm, and 5 mm are typical. While explicit tolerances are not detailed in the clauses provided, general manufacturing tolerances usually approximate ±0.5 mm for leg lengths and ±0.2 mm for thickness. Bundles must be marked with designation, alloy, temper, manufacturer details, and batch information as per marking clauses.
Moments of inertia are defined about principal axes X-X and Y-Y as well as principal axes U-U (maximum) and V-V (minimum) passing through the centroid. Radii of gyration are calculated as the square root of the moment of inertia divided by the sectional area, with formulas: r_x = √(I_x/a), r_y = √(I_y/a), r_u = √(I_u/a), and r_v = √(I_v/a). These parameters are essential for structural analysis and design of aluminium equal leg angles according to the standard.
Manufacturers are required to mark each bundle or lot with the product designation, alloy and temper information, manufacturer’s name, and lot number or year of production. The ISI Certification Mark may be applied optionally to signify compliance and quality assurance under ISI supervision. Packaging involves secure bundling, typically wrapped in bituminized hessian cloth or wooden cases, with bundle weight determined by mutual agreement between manufacturer and purchaser to ensure protection during transportation.
The standard does not explicitly address or specify the production of aluminium equal leg angles featuring a square root fillet radius. It primarily covers general dimensional and sectional properties with standard or rounded root radii. Manufacturing such angles with a square root radius would require mutual agreement between buyer and supplier and appropriate engineering validation, as this is not standardized within the current provisions.
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