Corrugated Steel Pipe, Polymer Precoated for Sewers and Drains

A762/A762M- 15: Standard Specification for Corrugated Steel Pipe, Polymer Precoated for Sewers and Drains

When designing and implementing vital infrastructure like storm water drainage and culvert systems, selecting materials that offer long-term durability and corrosion resistance is paramount. ASTM A762/A762M- 15 provides engineers and specifiers with an essential, industry-leading standard for polymer precoated corrugated steel pipe, ensuring robust performance in demanding civil engineering applications.

What is A762/A762M- 15?

ASTM A762/A762M- 15 is the authoritative standard specification for corrugated steel pipe that has been precoated with a polymer layer over a metallic base coating. Developed by ASTM International, this standard ensures that the pipe is suitable for critical applications such as storm water drainage, culverts, and underdrains, offering enhanced protection against environmental degradation.

Scope & Purpose

This comprehensive standard governs the materials and manufacturing processes for polymer precoated corrugated steel pipe intended for gravity flow applications, primarily for storm water conveyance. It specifies requirements for the steel sheet, metallic coatings (such as zinc, aluminum-zinc, or zinc-aluminum-mischmetal alloys), and the subsequent polymer precoating applied to both the interior and exterior surfaces. The standard explicitly excludes requirements related to installation practices, bedding, backfill, or the structural design calculations concerning earth cover loads, which are addressed in separate practices.

Who Must Comply?

• • Primary audience: Civil Engineers, Structural Engineers, Project Managers, Construction Managers, and Material Specifiers involved in infrastructure development.
• • Industries affected: Civil Engineering, Construction, Public Works, Transportation, and Infrastructure Development.
• • Compliance nature: Typically voluntary, but often mandated by project specifications, municipal codes, or government regulations for public works projects.
• • Enforcement: Compliance is generally verified through project submittals, material testing, and site inspections by owners' representatives or third-party testing agencies.

Key Requirements Overview

The standard requires that the corrugated steel pipe be fabricated from steel sheet that conforms to ASTM A742/A742M, which details metallic and polymer precoated steel sheets. Professionals must ensure that the metallic coating (e.g., zinc, 55% aluminum-zinc) provides the initial layer of corrosion protection, with the polymer precoating offering an additional barrier against abrasion and chemical attack. Key provisions include specifying the type of metallic coating, the grade and thickness of the polymer coating on both sides, and the pipe's geometric configuration (e.g., circular, pipe-arch, perforated). The standard also addresses requirements for coupling bands and gaskets to ensure proper joint integrity.

Related Standards & References

ASTM A762/A762M- 15 is often used in conjunction with other ASTM standards to ensure a complete and robust system. ASTM A742/A742M defines the requirements for the metallic and polymer precoated steel sheet used in fabrication. For structural design considerations and installation guidance, ASTM A796/A796M (Structural Design) and ASTM A798/A798M (Installation Practice) are essential complementary documents.