Stainless Steel 321/321H Seamless Pipes Manufacturer, Supplier
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Midland Alloys is a premier manufacturer, stockist, and exporter of high-quality Stainless Steel 321/321H Seamless Pipes. Specifically engineered for high-temperature applications and corrosive environments, our pipes are manufactured in compliance with international standards, including ASTM, ASME, DIN, and EN.
As a trusted SS 321/321H Seamless Pipe supplier, we provide solutions to industries ranging from aerospace and chemical processing to oil and gas, ensuring durability and superior performance under extreme thermal conditions.
What are Stainless Steel 321/321H Seamless Pipes?
Stainless Steel 321 (UNS S32100) is an austenitic stainless steel stabilized by Titanium. It offers excellent resistance to intergranular corrosion after exposure to temperatures in the chromium carbide precipitation range of 800–1500°F (427–816°C).
Stainless Steel 321H (UNS S32109) is the higher carbon version of the alloy, specifically designed to provide improved high-temperature creep strength and higher strength at temperatures above 1000°F (537°C).
Benefits: SS 321/321H Seamless Pipes
- Cost-Efficient Welding: No post-weld annealing is required, significantly reducing installation time and labor costs.
- Extreme Durability: Offers higher stress-rupture properties than SS 304, ensuring a longer service life in refineries and power plants.
- Versatile Performance: Excellent toughness even at cryogenic temperatures, making it suitable for volatile temperature swings.
- Seamless Reliability: Our seamless manufacturing process eliminates weld-seam vulnerabilities, ideal for high-pressure environments.
Technical Specifications of Stainless Steel 321 / 321H Seamless Pipes
Seamless Pipe OD : 1/8 -12" NPS
ASTM A312 / ASME SA312
Seamless
Round, Square, Rectangular, Hydraulic Etc
Single Random, Double Random & Cut Length.
Plain End, Beveled End, Treaded
SCH5, SCH10, SCH20, SCH30, SCH40, STD, SCH80, SCH 80S, SCH60, SCH80, SCH120, SCH140, SCH160, SCH XXS, SCH XS
No. 2B - Mill finish/ Matte finish, No.8 - Mirror finish, No. 4 - Brushed finish, Bright, Annealing, Polished, Mirror
Contact us today to discuss how Stainless Steel 321/321H Seamless Pipes can benefit your application. Whether you need guidance in selecting the right pipes or have specific requirements, our team of experts is here to help you find the optimal solution.
Technical Details & Delivery Condition
| Feature | Stainless Steel 321 | Stainless Steel 321H |
| Material Type | Titanium-stabilized austenitic stainless steel | High-carbon titanium-stabilized austenitic stainless steel |
| Carbon Content | Max 0.08% | 0.04% – 0.10% (higher carbon) |
| UNS Number | UNS S32100 | UNS S32109 |
| DIN / EN Equivalent | DIN 1.4541 | DIN 1.4878 |
| Stabilizing Element | Titanium (Ti) | Titanium (Ti) |
| Temperature Resistance | Good resistance up to ~870°C | Excellent resistance up to ~900–950°C |
| Creep Strength | Moderate | Higher creep strength |
| High-Temperature Performance | Suitable for continuous moderate heat | Preferred for sustained high-temperature service |
| Corrosion Resistance | Excellent resistance to intergranular corrosion | Excellent, similar to SS 321 |
| Oxidation Resistance | Very good | Superior at elevated temperatures |
| Weldability | Excellent, no post-weld heat treatment required | Excellent, stable during welding |
| Mechanical Strength | Good | Higher tensile and yield strength |
| Typical Applications | Exhaust manifolds, chemical processing, heat exchangers | Boilers, superheaters, high-temperature process piping |
| Availability | Widely available | Available but more application-specific |
Stainless Steel Seamless Pipe Grades We Offer
How Stainless Steel 321/321H Seamless Pipes Are Manufactured
Round Bar
Analytic
Cut to Length
Centering
Heating
Perforation
Inspection of Size
Pickling
Inspection of Surface
Lubricating
Cold Drawing (Cold Rolling)
Degreasing
Annealing
Straightening
Cut
Pickling / Passivating
Inspection
Analytic
Marking
Packing & Shipping
Applications of ASTM A312 TP 321 Seamless Pipes
Why Choose Midland Alloys?
- Expert Manufacturer: Decades of experience in stainless steel fabrication.
- Extensive Stock: We maintain a huge inventory of SS 321/321H Seamless Pipes for fast delivery.
- Competitive Pricing: Factory-direct pricing that delivers maximum value without compromising on quality or compliance.
- Customization: We offer a wide range of schedules, finishes, and lengths, fully customized to meet specific project requirements.
- Certification: All products are supplied with Mill Test Certificates (MTC) as per EN 10204 3.1.
