Stainless Steel 321/321H Tubes Manufacturer & Supplier
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Midland Alloys is one of the trusted stainless steel 321 tube manufacturers in India, offering premium quality tubes designed for demanding applications. Our Stainless Steel 321/321H Tubes are manufactured with modern procedures that ensure precision, consistency and outstanding performance. These tubes are stabilized with titanium, making them resistant to intergranular corrosion and stress corrosion cracking at temperatures up to about 302°F (150°C). We manufacture in full accordance with ASTM A312 / ASME SA312 standards, producing goods that meet global industrial needs. Our tubes are perfect for high-temperature and corrosive conditions as they come in sizes ranging from 1/8″ NB to 24″ NB, with an outer diameter range of 6.00 mm OD to 914.4 mm OD, and surface treatments like No.1, No.4, No.8 Mirror Finish, and 2B. With years of experience and a global supply network, we ensure timely delivery and unmatched quality for SS 321 seamless tubes worldwide.
Benefits of AISI SS TP 321H Tubing
AISI SS TP 321H Tubing offers outstanding performance in high-temperature and corrosive environments.
- High-temperature strength ensures long-term stability in heat-intensive conditions.
- Corrosion resistance extends service life in chemical and marine environments.
- Heat resistance allows performance in elevated temperature operations.
- Creep strength prevents deformation under mechanical stress at high heat.
- Weldability and formability make fabrication easier without compromising durability.
Specification of 321/321H Stainless tube

Seamless Tube OD : 1 / 2" NB - 16" NB
Welded Tube OD : 1 / 2" NB - 24" NB
EFW Tube Size : 6.00 mm OD up to 914.4 mm OD

ASTM A213, A269, A249, A511, A554 / ASME SA213, SA269, SA249, SA511, SA554

Seamless / Welded / ERW / Fabricated / CDW / 100% X Ray Welded

Round, Square, Rectangular, Hydraulic Etc

Single Random, Double Random, Standard & Cut length

Plain Ends (PE), Threaded Ends (TE), Bevelled Ends (BW), Grooved Mechanical Joints or Grooved Ends, TBE (Treaded Both Ends)

SCH 5, SCH10, SCH 40, SCH 80, SCH 80S, SCH 160, SCH XXS, SCH XS

2B, No.4, No.1, No.8 Mirror Finish for Stainless Steel Tubes, Finish as per customer Requirements
Contact us today to discuss how Stainless Steel 321/321H Tubes can benefit your application. Whether you need guidance in selecting the right Tubes or have specific requirements, our team of experts is here to help you find the optimal solution.
Technical Details & Delivery Condition
| Grade | Ni | C | Mn | P | S | Si | Cr | Mo | N | TI | |
| 321 | Max | 12.00 | 0.08 | 2.00 | 0.045 | 0.030 | 1.00 | 19.0 | 3 – 4 | 0.10 max | 0.70 |
| Min | 9.00 | – | – | – | – | – | 17.0 | – | – | 5(C+N) | |
| 321H | Max | 12.00 | 0.08 | 2.00 | 0.045 | 0.030 | 1.75 | 19.0 | 3 – 4 | 0.10 | 0.70 |
| Min | 9.00 | 0.04 | – | – | – | – | 17.0 | – | – | 4(C+N) | |
| Grade | Tensile Strength (MPa) min | Yield Strength 0.2% Proof (MPa) min | Elongation (% in 50mm) min | Hardness | |
| Rockwell B (HR B) max | Brinell (HB) max | ||||
| 321 | 515 | 205 | 40% | 95 | 217 |
| 321H | 515 | 205 | 40% | 95 | 217 |
| STANDARD | WERKSTOFF NR. | UNS |
| SS 321 | 1.4541 | S32100 |
| SS 321H | 1.4878 | S32109 |
Stainless Steel Tubes Grades We Offer
321/321H Stainless Steel Capillary Tube vs 347 Stainless Steel Tube
The main difference between 321/321H Stainless Steel Capillary Tube and 347 stainless steel tube lies in their stabilizing elements. Type 321/321H is titanium-stabilized, which provides exceptional resistance to intergranular corrosion and allows for extended use at high temperatures. In contrast, 347 stainless steel is stabilized with niobium, giving it significantly superior resistance to sensitization in some harsh conditions. For applications involving prolonged exposure to temperatures between 800°F and 1500°F, 321/321H tubes often provide better weld stability and mechanical performance.
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
Application of DIN 1.4541 SS 321 Tubing
Stainless Steel 321 Cold Drawn Tubes are widely used in aerospace exhaust systems for their ability to handle high heat without losing strength. In the chemical and petrochemical industries, these tubes are used for processing equipment where resistance to aggressive chemicals is essential. Power plants utilize 321H Stainless Steel Seamless Tube in high-pressure steam pipe systems because of its durability and ability to wok reliably under extreme temperature and pressure circumstances.
Why Choose Midland Alloys Inc. for AISI SS TP 321H Tubing
Midland Alloys Inc. is a reputable UNS S32100 tube suppliers known for delivering top-quality 321H Stainless Steel EFW Tube to clients worldwide. Our operations are supported by certifications such as ISO 9001:2015, PED 2014/68/EU, and EN 10204 3.1/3.2 Mill Test Certificates, which ensure compliance with the highest quality requirements. We support third-party inspections from TÜV, BV, SGS, and DNV to give clients complete confidence in our products. Every tube is tested both in-house and by a third party, including hydrostatic testing for pressure resistance, ultrasonic testing for internal faults, radiographic testing for weld quality and PMI for grade confirmation. Mechanical testing such as tensile, hardness, flattening, and bend tests are performed according to order specifications. Our global clientele in the Middle East, Europe and Southeast Asia trust us for constant quality, professional service, and dependable supply.
FAQs – SS 317/317H Tubes
In their annealed state, these stainless steel tubes are generally non-magnetic. However, some magnetism may be present after cold working
They are available with plain ends, beveled ends, or threaded ends depending on the application requirements.
While these tubes excel in high-temperature environments, they can also perform in moderately low temperatures without losing toughness, making them versatile across industries.



