ASTM A403 WP304 Stainless Steel Sanitary Fitting 90 Degree Elbow For Food

The specific name of the ASTM A403 standard is "Standard Specification for Forged or Rolled Austenitic Stainless Steel Pipe Fittings". This standard specifies the materials, manufacturing processes, chemical composition, mechanical properties, dimensional tolerances, test methods and inspection rules for stainless steel pipe fittings such as elbows, tees, and caps used in piping systems to ensure that these fittings have consistent quality and performance.

Stainless Steel Sanitary Fitting 3A SMS BRIGHT SS304,SS316L

Manufacturing Requirements for ASTM A403 WP304 Food-Grade Pipe Fittings

• Manufacturing Requirements for ASTM A403 WP304 Food-Grade Pipe Fittings
• Manufacturing Process: ASTM A403 WP304 food-grade stainless steel pipe fittings are typically forged and rolled to ensure a dense, defect-free material.
• Heat Treatment: ASTM A403 WP304 food-grade stainless steel pipe fittings must undergo solution heat treatment to relieve processing stresses, dissolve carbides, and restore optimal corrosion resistance.
• Surface Finish: This is key to "food grade." The ASTM A403 standard itself may not directly specify a specific surface roughness (Ra value), but the food industry often has additional requirements. A common food-grade surface requirement is mechanical polishing or electropolishing to achieve a very smooth surface (e.g., Ra ≤ 0.8 μm or less), often referred to in the industry as a "food-grade finish."

Why is ASTM A403 WP304 stainless steel fitting suitable for use in the food industry?

• Excellent corrosion resistance: 304 stainless steel contains approximately 18% chromium and 8% nickel. The chromium forms an extremely dense, transparent chromium oxide passivation film on the pipe surface, giving the steel its "stainless" and "corrosion-resistant" properties, effectively resisting corrosion from water, steam, various organic acids, and food acids.
• High cleanliness and ease of cleanability: ASTM A403 standard requires fittings to have smooth internal and external surfaces free of defects, cracks, and embedded contaminants. This effectively prevents bacterial harborage and material residue, while also making cleaning easy and hygienic.
• Excellent mechanical properties: 304 stainless steel possesses sufficient strength and toughness to withstand the operating pressures and various mechanical stresses of piping systems.
• Non-polluting properties: 304 stainless steel is inherently stable and will not release harmful substances into food, ensuring food safety.