How to Select and Inspect Raw Materials for Stainless Steel Water Tanks？

The raw materials for the stainless steel water tanks we commonly encounter are mainly made of food-grade stainless steel sheets, using stamping forming technology. The appropriate material is chosen based on the usage scenario:

• Conventional water quality (such as domestic water): SUS304 stainless steel (18% chromium, 8% nickel) is selected, which has strong corrosion resistance and meets the GB/T 3280-2015 standard.
• Special environments (such as coastal areas with high salt mist or industrial wastewater): SUS316L stainless steel (containing 2-3% molybdenum) is chosen, which has superior resistance to chloride ion corrosion.
• The thickness of the stainless steel sheets is determined based on the tank volume and pressure requirements. Common specifications range from 0.8mm to 4mm (thinner sheets for small tanks, thicker sheets for larger tanks or areas subjected to high pressure).

How to inspect theraw materials?

• Chemical composition testing: The chemical composition of the stainless steel sheet, including chromium, nickel, carbon, etc., is analyzed using a spectrometer to ensure compliance with the corresponding material standards (e.g., carbon content of SUS304 stainless steel ≤ 0.08%).
• Physical performance inspection: The yield strength (≥205 MPa), tensile strength (≥520 MPa), and elongation (≥40%) of the sheet are tested to ensure that the material will not crack easily during stamping.
• Surface quality inspection: The surface of the sheet is visually inspected or checked with instruments to ensure there are no defects such as scratches, oxide scales, or oil stains (which could affect stamping and subsequent welding processes).