The inspection of galvanized steel pipes is to ensure that they meet relevant standards and usage requirements, including a series of tests on physical properties, chemical properties, and process performance. The following are some of the main items and key points of galvanized steel pipe inspection:
1. Appearance quality inspection: Check the thickness, uniformity, and surface defects of the galvanized layer (such as zinc nodules, leakage, cracks, scratches, etc.).
2. Mechanical properties test: Including tensile strength, yield strength, elongation, etc., to evaluate the pressure bearing capacity and toughness of the steel pipe.
3. Chemical composition analysis: Detect the chemical composition of the steel pipe base material and the galvanized layer to ensure that the material meets the specified standards.
4. Galvanized layer adhesion test: Test the bonding strength of the galvanized layer and the steel pipe base by cutting, bending, or hammering.
5. Corrosion resistance test: Simulate actual environmental conditions to test the corrosion resistance of galvanized steel pipes in acid, alkali, salt spray, high temperature, and other environments.
6. Dimensional accuracy test: Accurately measure the outer diameter, wall thickness, length, and other dimensions of the steel pipe to ensure that it meets the design and use requirements.
7. Welding performance test: For galvanized steel pipes that need to be welded, the performance of the welding parts must also be tested.
The testing standards for galvanized steel pipes mainly include national standards GB/T 3091-2015 “Welded steel pipes for low-pressure fluid transportation” and GB/T 13793-2008 “Straight seam electric welded steel pipes”, as well as GB/T 15393-2014 “Metallic covering layer, hot-dip galvanized layer of steel parts, technical requirements and test methods”. In import and export trade, the international standard ISO 1461:2015 or other relevant countries’ standards may also be used for testing.
The testing process usually includes sample reception and recording, appearance inspection, dimension measurement, galvanized layer thickness detection, mechanical properties test, chemical composition analysis, corrosion resistance test, and finally issuing a test report.
Post time: May-19-2025