Meta Description:Explore the key differences between TP304, TP316, TP321, and other stainless steel tube grades. Learn how to choose the right material based on corrosion resistance, temperature, mechanical strength, and compliance with ASTM and EN standards. Introduction Choosing the correct stainless steel tube grade is crucial for ensuring performance, longevity, and regulatory compliance in industries such as oil & gas, chemical processing, power generation, food and beverage, and marine. This guide compares the most commonly used tube grades—TP304, TP316, TP321, and extends to TP347, 904L, Duplex 2205, and Super Austenitic Alloys—with detailed references to international standards. 1. Overview of Common Stainless Steel Tube Grades Grade UNS No. EN No. Key Standards Typical Applications TP304 S30400 1.4301 ASTM A213, A269, A312 General process piping, food equipment TP304L S30403 1.4307 ASTM A213, A312 Low carbon version of 304; better weldability TP316 S31600 1.4401 ASTM A213, A312 Improved corrosion resistance (Mo added) TP316L S31603 1.4404 ASTM A213, A312 Preferred for welding and marine use TP321 S32100 1.4541 ASTM A213, A312 Ti-stabilized, high-temp applications TP347 S34700 1.4550 ASTM A213, A312 Nb-stabilized alternative to TP321 904L N08904 1.4539 ASTM B677, B673 High nickel, chloride-rich environments 2205 S32205 1.4462 ASTM A789, A790 Duplex: high strength +
