Steel, Structural Tubing, Cold Formed, Welded, Carbon, Zinc-Coated (Galvanized) by the Hot-Dip Process

A1057/A1057M: Standard Specification for Steel, Structural Tubing, Cold Formed, Welded, Carbon, Zinc-Coated (Galvanized) by the Hot-Dip Process

For engineers and manufacturers seeking robust, corrosion-resistant structural components, adhering to industry-leading standards is paramount. ASTM's A1057/A1057M specification provides an essential framework for specifying and procuring cold-formed, welded carbon steel structural tubing that has been hot-dip galvanized. This comprehensive standard ensures a proven level of quality and performance for critical applications across numerous industries.

What is A1057/A1057M?

ASTM A1057/A1057M is an authoritative standard that defines the requirements for cold-formed, electric resistance or induction welded carbon steel structural tubing. This tubing is specifically designed for applications demanding enhanced corrosion resistance through hot-dip galvanization on its exterior surface. The standard ensures consistent mechanical properties and coating integrity, originating from ASTM's commitment to materials excellence.

Scope & Purpose

This specification governs the production and procurement of exterior zinc-coated (galvanized) cold-formed welded carbon steel structural tubing. It applies to round, square, rectangular, and special shapes, manufactured from either hot-rolled or cold-rolled steel, and processed on continuous coating lines. The standard details requirements for coating weight, adhesion, base metal chemistry, and mechanical properties, ensuring suitability for environments where corrosion is a concern. Notably, it does not cover the interior surface coating or tubing intended for pressure applications.

Who Must Comply?

• • Primary audience: Material engineers, design engineers, quality control inspectors, production managers, and welders involved in the fabrication and use of structural tubing.
• • Industries affected: Steel Manufacturing, Construction, Automotive, General Manufacturing, Agriculture, and any sector utilizing structural steel elements requiring corrosion protection.
• • Compliance nature: While adoption is generally voluntary, compliance is often contractually mandated or required by project specifications.
• • Enforcement: Compliance is typically verified through material certifications, independent testing, and quality assurance audits by specifiers, clients, or regulatory bodies.

Key Requirements Overview

• • The standard requires that the structural tubing be cold-formed and electric resistance or induction welded, with zinc coating applied exclusively to the exterior surface via the hot-dip process.
• • Professionals must ensure that the tubing meets specified coating weight and adhesion requirements, preventing delamination of the zinc coating.
• • Key provisions include adherence to defined chemical composition limits for the base carbon steel and specific mechanical property thresholds, such as tensile strength and yield strength.
• • The specification details acceptable dimensions for round, square, rectangular, and special shapes, along with permissible variations.
• • Testing procedures for coating weight (using Test Method A90/A90M) and mechanical properties (aligned with Specification A500/A500M) are critically outlined.

Related Standards & References

ASTM A1057/A1057M is deeply integrated within a robust framework of material standards. Complementary standards include ASTM A500/A500M, which covers the base cold-formed welded and seamless carbon steel structural tubing, providing essential mechanical and dimensional requirements before galvanization