AS/NZS 1579

Technical Overview: AS/NZS 1579 – Arc-Welded Steel Pipes and Fittings for Water and Wastewater

1. Definition and Scope

قياسي: AS/NZS 1579 (latest edition: AS 1579:2001) specifies requirements for arc-welded steel pipes and fittings with butt welds, used in water supply, wastewater systems, and piling applications.

التطبيقات:

Pressurized water/wastewater transport (up to 6.8 MPa).

Structural piling (e.g., foundation support).

Product Range: Pipes with nominal diameters ≥ DN 100 mm (4 inches).

2. Key Requirements

Dimensions and Tolerances

القطر: DN 100 mm and above. Exact size ranges are tabulated in the standard (e.g., DN 100–DN 3000+).

سُمك الجدار: Varies by pressure class; minimum thickness defined to withstand operational stresses.

Tolerances (typical examples, based on industry norms):

3. Material and Performance Grades

Steel Grades: Not explicitly detailed in search results, but typical grades include AS/NZS 3678 (e.g., Grade 250, 350) for weldability and corrosion resistance.

الخواص الميكانيكية (representative values):

التركيب الكيميائي:

Limits for الكربون (C), المنجنيز (Mn), الكبريت (S), الفوسفور (P) to ensure weld integrity and corrosion resistance (e.g., S ≤ 0.03%, P ≤ 0.03%).

Testing and Inspection

Compulsory inspection for quality and safety:

الاختبار الهيدروستاتيكي:

Each pipe was tested at ≥1.5x design pressure (minimum). 10.2 and 6.8 MPa systems).

Duration: ≥5 seconds without leakage.

Non-Destructive Testing (NDT):

Radiographic/ultrasonic testing in case of welds for crack/imperfections1.

Dimensional Checks:

OD, wall thickness, straightness, and length confirmed to within tolerances.

الفحص البصري:

Possible surface imperfections (e.g. Cracks, undercuts) shall meet the acceptance standards.

4. Ancillary Requirements

Linings/Coatings: Optional cement mortar lining per AS 1281 for corrosion protection.

Fittings: Must match pipe material and pressure ratings (e.g., elbows, reducers).

Marking: Each pipe marked with:

Standard number (AS 1579:2001).

Manufacturer ID.

Size (DN), pressure rating, and heat number.

5. Evolution and Current Status

Versions:

1973: Covered water/gas pipelines.

1993: Expanded to wastewater and piling.

2001 (Revision): Unified specimen and test procedures and reference standards such as AS 1199 (sampling) and AS 1646 (seals).

Superseding Status: AS 1579:2001 is active and replaces all older versions.

Importance in Infrastructure

Guarantees a durable performance under high pressure (for example, municipal water systems).

Leads to standardized connection between pipes/fittings at different projects.

Essential for hazardous locations (i.e., wastewater with H2S gas)

6. Conclusion

AS/NZS 1579:2001 is the standard that defines their acceptance for arc-welded steel pipes in Australian and New Zealand water/wastewater industry. It requires strict material, dimension and testing stipulations to guarantee that the product is suitable for use in high pressure systems. The standard provides the metal tolerances, core tolerances are included (ID ±1 mm, OD ±1%, wall thickness ±10-12%, but overall toleramces are precise on mechanical/chemical aspect only including skin pass rolling, but filled party may vary (supported by referenced material standards such as AS/NZS 3678). Engineers need to comply with its compliance & safety.