Judging the quality of galvanized pipes is a comprehensive evaluation process. In addition to checking the thickness, key data such as adhesion and salt spray test results should also be considered.
Uniformity: A high-quality galvanized layer should be uniform and continuous, without defects such as incomplete coating or black spots. This can be tested by immersion in a copper sulfate solution; if it does not turn red (no copper color) after five consecutive immersions, it is considered合格 (qualified).
Adhesion: The zinc layer should be firmly bonded to the steel pipe substrate. This can be checked by a bending test (e.g., bending 90° or 180°); a qualified galvanized layer should not peel off or crack.
Surface Quality: Visually inspect the surface; it should be smooth, without severe defects such as zinc nodules, peeling, or bubbles.
Chemical Composition Analysis: Test the content of elements such as carbon, manganese, silicon, sulfur, and phosphorus in the steel pipe substrate to ensure that the material meets standards.
Mechanical Property Testing: This includes tensile tests (tensile strength, yield strength) and impact tests (toughness) to ensure that the pipe has sufficient strength and toughness.

When purchasing galvanized steel pipes, a reliable method is to request the supplier to provide an authoritative testing report.

Time：09/07/2026 16:24:24

Answers

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