I. Overview of 304 Stainless Steel Seamless Pipe
304 stainless steel seamless pipe is an austenitic stainless steel pipe widely used in various industrial, food, chemical, and construction piping systems due to its excellent corrosion resistance, high-temperature resistance, and good mechanical properties.
Key Features
Superior Corrosion Resistance: Resists most chemical media, acids, alkalis, and atmospheric corrosion.
Excellent High-Temperature Performance: Suitable for general high-temperature piping and liquid transfer systems.
Outstanding Mechanical Properties: Stable tensile and yield strengths, high elongation, and excellent weldability.
Seamless Construction: High structural integrity with superior pressure resistance compared to welded pipes.
Smooth Surface Finish: Available with brushed, polished, mirror-finished, and other surface treatments to meet industrial and decorative requirements.
Application Fields
Food Processing & Beverage Industry: Conveys water, beverages, beer, etc.
Pharmaceutical Equipment Piping: Corrosion-resistant and easy to clean.
Chemical Pipeline Systems: Transports acidic/alkaline liquids and gases.
Construction & Decorative Engineering: Handrails, pipe racks, curtain walls.
Mechanical Equipment: Hydraulic piping, cooling systems, steam pipes.
II. Common Standards for 304 Stainless Steel Seamless Pipes
Standard System Standard Number Applicable Scope / Description USA ASTM / ASME ASTM A312 / ASME SA312 High-quality austenitic stainless steel seamless and welded pipes; widely used in chemical, food, pharmaceutical, mechanical, and construction piping China GB / T GB/T 14976 Stainless steel seamless pipes for industrial and construction use; specifies chemical composition, dimensions, and mechanical properties Europe EN EN 10216-5 Austenitic stainless steel seamless pipes for pressure pipelines; suitable for high-temperature and high-pressure fluid transport Japan JIS JIS G3459 Austenitic stainless steel seamless pipe standard; mainly used in chemical, steam, and fluid transport pipelines
III. Theoretical Weight Table for 304 Stainless Steel Seamless Pipes (Partial List of Common Specifications)
Outer diameter (mm) Wall thickness (mm) Theoretical weight (kg/m) 10 1.0 0.22 15 1.5 0.55 20 2.0 0.98 25 2.5 1.53 32 3.0 2.27 40 4.0 3.63 50 4.5 5.05 65 5.0 7.40 80 5.0 9.87 100 6.0 15.44 125 6.0 19.18 150 8.0 30.43 200 10.0 53.20 250 12.0 83.00 300 15.0 126.50
IV. Corresponding international grades of 304 stainless steel in different countries and standards systems
Country / Standard System Standard Number Corresponding Grade China (GB) GB/T 20878 06Cr19Ni10 USA (ASTM / AISI) ASTM / AISI 304 USA (UNS) UNS S30400 Europe (EN) EN 10088 X5CrNi18-10 Germany (DIN) DIN 10088 1.4301 Japan (JIS) JIS G4305 / G4304 SUS304 International (ISO) ISO 15510 X5CrNi18-10 Russia (GOST) GOST 5632 08Х18Н10 South Korea (KS) KS STS 304 France (AFNOR) NF A35-573 Z5CN18-09 UK (BS) BS 1449 304S31 Italy (UNI) UNI X5CrNi18-10 Spain (UNE) UNE X5CrNi18-10
V. What are the differences between 304 and 304L stainless steel?
Comparison Item 304 Stainless Steel 304L Stainless Steel Carbon Content (C) ≤ 0.08% ≤ 0.03% (Low Carbon) International Grade AISI 304 / UNS S30400 AISI 304L / UNS S30403 European Grade EN 1.4301 EN 1.4307 Intergranular Corrosion Resistance Moderate Better Post-Weld Heat Treatment Required May be needed for thick-walled pipes Usually not required Strength Slightly higher Slightly lower (difference minimal) Price Slightly lower Slightly higher
VI. Comparison Table of 304 Stainless Steel Seamless Tubes vs. Welded Tubes
Comparison Item 304 Stainless Steel Seamless Pipe 304 Stainless Steel Welded Pipe Manufacturing Process Hot-rolled, hot-pierced, or cold-drawn; seamless Stainless steel strip rolled and welded; commonly ERW / TIG / MIG / SAW Weld Condition Seamless, uniform and smooth pipe body Has weld seam; can be pickled or polished; weld is smooth and reliable Outside Diameter Range Φ6 – Φ508 mm (large diameters customizable) Φ6 – Φ219 mm (standard stock; large diameters require SAW/LSAW) Wall Thickness Range 0.5 – 50 mm 0.5 – 8 mm (standard) Pressure Performance High; suitable for high-pressure, chemical, and steam pipelines Medium–low pressure; thick-wall large-diameter pipes can handle high pressure (SAW/LSAW) Cost Relatively high Lower; suitable for large-scale projects Typical Applications High-pressure pipelines, chemical, petrochemical, steam, engineering pipelines Water supply and drainage, food & beverage, machinery, construction, medium–low pressure pipelines Summary of Features High pressure resistance, heat resistant, seamless Low cost, flexible dimensions, reliable welds
VII. Testing Standards for 304 Stainless Steel Seamless Pipes
Inspection Item Test Content Standard / Method Chemical Composition C, Si, Mn, P, S, Cr, Ni ASTM A312 / EN 10088 Mechanical Properties Tensile strength, yield strength, elongation ASTM A370 Dimensional Inspection Outside diameter, wall thickness, ovality, length ASTM A999 / ASME B36.19 Surface Quality Surface defects, cracks, folds ASTM A999 Non-Destructive Testing (NDT) Eddy current testing (ET) ASTM E426 Pressure Test Hydrostatic test ASTM A999 Corrosion Resistance (Optional) Intergranular corrosion test ASTM A262 Quality Documentation Material Test Certificate (MTC) EN 10204 3.1
VIII. Procurement Recommendations and Process for 304 Stainless Steel Seamless Tubing
1. Procurement Recommendations for 304 Stainless Steel Seamless Tubing
Key Point Recommended Action Material Confirmation Specify 304 / 304L; request EN10204 3.1 Material Test Certificate (MTC) Applicable Standards Commonly ASTM A312 / A213; clearly indicate the specific standard required for the project Specifications & Dimensions Confirm outside diameter, wall thickness, length, and tolerance requirements Service Conditions Check if welding is required, design pressure, temperature, and type of conveyed medium Inspection Requirements Chemical composition, mechanical properties, eddy current testing (ET), hydrostatic test Surface Condition Pickled / Solution annealed / Polished (specify if required) Packaging & Transportation Export-grade packaging; specify wooden crates or moisture-proof packing if needed Documentation MTC, inspection reports, third-party inspection (optional)
2. Standard Procurement Process for 304 Stainless Steel Seamless Tubes
Step Process Description 1 Confirm technical parameters (material, standard, specifications, quantity) 2 Supplier quotation and technical confirmation 3 Sample or document review (if required) 4 Sign contract / purchase order (PO) 5 Raw material procurement and production 6 Factory inspection and quality testing 7 Provide Material Test Certificate (MTC) / inspection reports 8 Packaging, shipment, and logistics 9 Delivery acceptance and inspection
3. Common Procurement Risk Warnings
Only specifying “304” without indicating the applicable standard
Failure to require non-destructive testing/hydrostatic testing
Welding conditions not selected for 304L
Neglecting wall thickness negative deviation.
