Shiny 304 stainless steel pipes arranged in bundles inside a factory, reflecting smooth metallic surfaces of different diameters.

304 Stainless Steel Standard Sizes of Pipes – Dimensions, Chart, and Weight 2025

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304 Stainless Steel Standard Sizes of Pipes – Complete Guide (2025 Edition)

Among the various grades of stainless steel, 304 stainless steel is the most widely used material for pipes and tubes in industries around the world. Its excellent corrosion resistance, strength, and durability make it ideal for applications in plumbing, food processing, construction, and chemical industries.

This comprehensive 2025 guide explains the standard sizes, thicknesses, and dimensions of 304 stainless steel pipes, including the relevant ASTM and IS standards, real-world applications, and FAQs.

Understanding 304 Stainless Steel

304 stainless steel belongs to the austenitic family of steels and contains around 18% chromium and 8% nickel, which is why it’s also referred to as 18/8 stainless steel.

It is non-magnetic in the annealed condition and has excellent forming and welding properties.
304 grade is the base metal for many variants like 304L (low carbon) and 304H (high carbon), each designed for specific uses.

Key Properties:

  • Density: 7.93 g/cm³

  • Melting Point: 1400–1450°C

  • Yield Strength: 205 MPa

  • Tensile Strength: 515 MPa

  • Elongation: 40%

Why 304 Stainless Steel Pipes Are So Common

304 stainless steel offers the best combination of performance and price, making it suitable for more than 50% of all stainless applications globally.

Advantages Include:

  1. High corrosion resistance in normal and mildly corrosive environments.

  2. Ease of fabrication and excellent weldability.

  3. Aesthetic finish for architectural designs.

  4. Durability and long service life.

  5. Wide availability in multiple diameters and schedules.

Applicable Standards

The standard specifications for 304 stainless steel pipes are defined by international norms:

Standard Description
ASTM A312 Seamless and welded austenitic stainless steel pipes for high-temperature and general service.
ASTM A554 Welded stainless steel mechanical tubing (decorative and structural use).
ASME B36.19M Standard dimensions for stainless steel pipes.
IS 1239 / IS 3589 Indian standards for mild and stainless steel pipes.

304 Stainless Steel Pipe Size Chart (Nominal Bore, OD, and Thickness)

Below is the ASME B36.19M standard chart for 304 stainless steel pipe sizes and thickness (Schedule 10S, 40S, 80S).

Nominal Pipe Size (NPS) Outside Diameter (mm) Schedule 10S Thickness (mm) Schedule 40S Thickness (mm) Schedule 80S Thickness (mm)
½ inch 21.3 1.65 2.77 3.73
¾ inch 26.7 1.65 2.87 3.91
1 inch 33.4 1.65 3.38 4.55
1¼ inch 42.2 1.65 3.56 4.85
1½ inch 48.3 1.65 3.68 5.08
2 inch 60.3 1.65 3.91 5.54
3 inch 88.9 1.65 4.78 7.62
4 inch 114.3 2.11 6.02 8.56
6 inch 168.3 2.77 7.11 10.97
8 inch 219.1 2.77 8.18 12.70
10 inch 273.0 3.05 9.27 12.70
12 inch 323.8 3.05 9.52 12.70
16 inch 406.4 3.40 9.53 12.70

Source: ASME B36.19M and ASTM A312 standards.

Types of 304 Stainless Steel Pipes

  1. Seamless Pipes (ASTM A312 TP304):
    Made from solid billets, seamless pipes have uniform strength and are ideal for high-pressure and heat applications.

  2. Welded Pipes (ASTM A554 TP304):
    More economical and widely used for decorative, structural, and low-pressure applications.

  3. ERW (Electric Resistance Welded):
    Produced by rolling and welding stainless sheets longitudinally, used in plumbing and fabrication.

  4. Square and Rectangular Pipes:
    Commonly used in architecture, furniture, and railing works.

Weight Chart for 304 Stainless Steel Pipes (per meter)

Pipe Size (mm) Wall Thickness (mm) Weight (kg/m)
25 x 1.5 1.5 0.89
38 x 2.0 2.0 1.54
50 x 2.0 2.0 2.05
63 x 2.5 2.5 3.15
76 x 3.0 3.0 4.30
100 x 3.0 3.0 5.68
150 x 4.0 4.0 11.25

Formula for weight calculation:
Weight (kg/m) = (OD – Thickness) × Thickness × 0.02466

Applications of 304 Stainless Steel Pipes

  1. Plumbing and Water Supply Systems – corrosion-free and hygienic.

  2. Food and Beverage Industry – sanitary-grade pipes for dairy and breweries.

  3. Chemical and Petrochemical Industries – resistant to mild acids and solvents.

  4. Architecture and Fabrication – railings, balustrades, and decorative tubing.

  5. Automotive and Mechanical Use – exhausts and structural components.

304 Stainless Steel vs. 316 Stainless Steel

Property 304 Stainless Steel 316 Stainless Steel
Composition 18% Cr, 8% Ni 16% Cr, 10% Ni, 2% Mo
Corrosion Resistance Excellent in mild environments Superior, especially in marine & chemical
Cost Lower Higher
Applications Domestic, food-grade, fabrication Marine, chemical, and oil industry

Advantages of Using Standard 304 Stainless Steel Sizes

  1. Compatibility: Fits standardized fittings and valves easily.

  2. Availability: Stocked by all major suppliers and fabricators.

  3. Interchangeability: Can be replaced or connected without modification.

  4. Ease of Design: Engineers can design systems knowing the standard OD and wall thickness.

Real-World Example

In 2024, a pharmaceutical plant in Pune replaced its MS pipelines with ASTM A312 TP304 seamless pipes to improve corrosion resistance and hygiene. The investment reduced annual maintenance costs by 35% and increased production uptime by 20%.

Common ASTM Standards for 304 SS Pipes

  • ASTM A312: Seamless and welded stainless steel pipes for general service.

  • ASTM A249: Welded pipes for boiler and heat exchanger applications.

  • ASTM A554: Welded mechanical tubing for structural and ornamental use.

  • ASTM A269: Seamless and welded tubing for general corrosion-resistant service.

Top 304 Stainless Steel Pipe Manufacturers and Dealers in India

  1. Jindal Stainless Ltd. – India’s leading manufacturer with ISI and ASTM certifications.

  2. Venus Pipes & Tubes Ltd. (Gujarat) – Specialized in seamless SS pipes.

  3. Ratnamani Metals & Tubes Ltd. (Ahmedabad) – Large-scale producer and exporter.

  4. Salem Stainless Steels Pvt. Ltd. (Tamil Nadu) – Major supplier of 304L and 316L grades.

  5. Navkar Steels (Delhi NCR) – Wholesale dealer for SS 304 decorative and industrial pipes.

Pricing Trends (2025)

304 stainless steel pipe prices fluctuate based on metal rates and thickness. Approximate retail prices in India (as of November 2025):

Pipe Size (OD mm) Thickness (mm) Price (₹/kg) Price (₹/meter)
25 mm 1.5 ₹270–₹290 ₹520–₹560
38 mm 2.0 ₹290–₹320 ₹700–₹850
50 mm 2.0 ₹310–₹330 ₹950–₹1100
63 mm 2.5 ₹320–₹340 ₹1250–₹1350
76 mm 3.0 ₹340–₹370 ₹1600–₹1800

Prices vary by region and supplier.

Summary

304 stainless steel pipes are available in a wide range of standard sizes defined by ASME B36.19M and ASTM A312 specifications.
They offer a perfect balance of corrosion resistance, strength, and affordability, making them suitable for plumbing, fabrication, and industrial applications.

Whether seamless or welded, 304 SS pipes remain the backbone of the stainless steel piping industry — widely stocked, easy to source, and compliant with international standards.

Frequently Asked Questions (FAQ)

Q1. What are the standard sizes of 304 stainless steel pipes?
Sizes range from ½ inch (21.3 mm OD) to 16 inch (406.4 mm OD) as per ASME B36.19M.

Q2. What is the wall thickness of 304 SS pipes?
Common schedules include 10S (1.65 mm), 40S (3–4 mm), and 80S (5–12 mm).

Q3. Which standard defines 304 stainless steel pipes?
ASTM A312 for industrial use and ASTM A554 for decorative pipes.

Q4. What is the difference between 304 and 304L stainless steel?
304L has lower carbon content, improving weldability and corrosion resistance near weld zones.

Q5. What is the weight of a 2-inch 304 SS pipe?
Approximately 5.44 kg/m as per standard dimensions.

Q6. Who are the top 304 SS pipe suppliers in India?
Jindal Stainless, Venus Pipes, and Ratnamani Metals are the leading suppliers.

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