When using galvanized steel pipes in Middle Eastern countries, due to the strong corrosiveness of the local climate (high temperature, high humidity, sand and dust, salt spray, etc.) on steel, the quality identification needs to be more rigorous. The following are the key points for evaluating the quality of galvanized steel pipes in the Middle Eastern environment:
01. Zinc Coating Quality and Anti - Corrosion Performance (Crucial)
Zinc Coating Thickness: In the Middle East, it is recommended to choose pipes with a zinc coating of ≥80μm (higher than the common national standard of 65μm). A magnetic thickness gauge can be used for detection.
Uniformity: Check whether the surface is free of uncoated areas, bubbles, or zinc nodules. Sand and dust tend to adhere to rough surfaces, accelerating corrosion.
Salt Spray Test Report: Require the supplier to provide a salt spray test report for at least 96 hours (the common standard is 72 hours) to ensure resistance to salt - spray corrosion.
02. Compatibility of Substrate and Process
Material Certification: It is advisable to choose hot - dipped galvanized steel pipes that meet international standards (such as ASTM A123). The substrate should be low - carbon steel (such as Q235 or equivalent materials).
Hot - Dip Galvanizing Process: Electro - galvanizing is prohibited in the Middle East (the zinc coating is thin and easy to fall off). Hot - dip galvanizing (Hot - Dip Galvanizing) must be used.
Weld Treatment: Check whether the welds have been ground and re - galvanized to avoid early rusting at the welds due to stress concentration.
03. Optimization for Environmental Adaptability
High - Temperature - Resistant Coating: If used in outdoor high - temperature environments (such as in Saudi Arabia and the United Arab Emirates), a high - temperature - resistant anti - corrosion paint (such as epoxy resin) can be required after galvanizing.
Packaging Protection: During transportation, the pipes should be wrapped with a moisture - proof film to prevent salt - spray erosion or zinc - coating abrasion by sand and dust during sea transportation.
04. Verification of Suppliers and Documents
Origin and Brand: It is advisable to choose galvanized pipes from China or European manufacturers, and avoid low - quality products from some regions in India and Southeast Asia.
Certification Documents: Verify third - party test reports (such as SGS) and MSDS (Material Safety Data Sheet) to ensure compliance with the import standards of Middle Eastern countries (such as SASO certification).
05. On - Site Quick Inspection Methods
Visual Inspection: The zinc coating should be a uniform silver - gray color, without blackening (oxidation) or white rust (due to improper storage).
Bending Test: Cut a sample and bend it 180°. There should be no peeling of the zinc coating or cracking of the substrate.
Weight Comparison: Under the same specifications, high - quality galvanized pipes are about 3% - 5% heavier than ordinary steel pipes (due to the higher density of zinc).
TYT Steel Pipe Factory
Common Risks of Inferior Pipes in the Middle East
Refurbished Pipes: There are grinding marks or partial zinc supplementation on the surface, and their service life is extremely short.
False - Marked Zinc Coating: The actual thickness is insufficient, and on - site instrument detection is required.
Lack of Anti - Rust Packaging: White rust appears on the pipes after they arrive at the port by sea, and they are directly scrapped.
Suggestion: For large - scale projects (such as the NEOM New City in Saudi Arabia), personnel can be sent to the factory for on - site supervision or a third - party inspection agency (such as BV, TUV) can be commissioned to ensure full - process quality control.
