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SS SMLS PIPE
- SS SMLS PIPE 2507 ASTM A790
- SS SMLS PIPE 2205 ASTM A790
- SS SMLS PIPE S31803 ASTM A790
- SS SMLS PIPE 904L ASTM A240
- SS SMLS PIPE TP321 ASTM A312
- SS SMLS PIPE TP310S ASTM A312
- SS SMLS PIPE TP316Ti ASTM A312
- SS SMLS PIPE TP316L ASTM A312
- SS SMLS PIPE TP316 ASTM A312
- SS SMLS PIPE TP304L ASTM A312
- SS SMLS PIPE TP304 ASTM A312
China TP321 Stainless Steel Seamless Pipes - Reliable Suppliers and Factory for Fast Delivery
Introduction
TP321 is a titanium-stabilized austenitic stainless steel designed for enhanced resistance to intergranular corrosion, particularly in high-temperature environments. It is part of the 300-series stainless steels, closely related to 304/304L, but with the addition of titanium (Ti) to mitigate carbide precipitation during welding or prolonged exposure to elevated temperatures. Below is a concise overview of its characteristics and applications.
Key Features
Intergranular Corrosion Resistance
Titanium stabilization ensures resistance to sensitization (chromium depletion) in welded or high-temperature (450°C–850°C) applications.
High-Temperature Stability
Maintains mechanical integrity and oxidation resistance up to 870°C (1600°F), suitable for exhaust systems, heat exchangers, and boilers.
Weldability
Excellent weldability without post-weld heat treatment, making it ideal for fabricated components.
General Corrosion Resistance
Resists oxidation, organic acids, and mildly corrosive environments, though less resistant to chlorides than 316/316L.
Material Specification
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Standard:ASTM A312/A312M
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O.D:1/8" NB TO 32" NB , (10.29MM-812.80MM) ,(Customization Available)
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W.T:SCH 10S, SCH 40S, SCH 80S, SCH160, SCH XXS (Customization Available)
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Application:
- Chemical & Petrochemical Industry
- Oil & Gas
- Fertilizer Plant
- Automotive & Aerospace
- Power Generation
- Food Processing
- Pharmaceutical & Biotechnology
- Pulp & Paper Industry
- Construction & Architecture
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End:Plain End, Beveled End, Threaded
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Processing:Cut-to-length; Polishing.
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Inspection:
- 100% PMI TESTED
- EN10204.3.1B MILL TEST CERTIFICATE
- THIRD PARTY INSPECTION ACCEPTED
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Delivery Condition:Cold Drawn, Annealed and Pickled/ Polished /Bright Annealed/ Sand blasting/ Shot Blasting.
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Marking:All SS SMLS Pipes are marked as follows: Standard, Grade, OD, Thickness, Length, Heat No. (Or as per the customer’s request)
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Packing:Packed in Wooden Boxes, plywood cases, Steel Strips Bundled, or as per Customers Requests
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Specials:Sizes and Specifications other than above can be customized on request.
Specification parameters
TP321 chemical composition
| HEAT NO. | CHEMICAL COMPOSITION (%) | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| C | Mn | P | S | Si | Ni | Cr | N | ||
| STAND. | MIN. | 9.00 | 17.00 | ||||||
| MAX. | 0.08 | 2.00 | 0.045 | 0.030 | 1.00 | 12.00 | 19.00 | 0.10 | |
TP321 Mechanical Properties
| Mechanical Properties | |||||
|---|---|---|---|---|---|
| Grade | Tensile Strength (MPa) min | Yield Strength 0.2% Proof (MPa) min | Elongation (% in 50mm) min | Hardness | |
| Rockwell B (HR B) | Brinell (HB) | ||||
| TP321 | 515 | 205 | 35 | 100 | 220 |
Equivalent Grades - (ASTM A312 TP321 Equivalent Grades)
| ASTM A312 TP321 Equivalent Grades | ||||||
|---|---|---|---|---|---|---|
| USA (ASTM/ASME/AISI) | Japan (JIS) | Germany (DIN/EN) | China (GB) | International (ISO) | United Kingdom(BS) | Russia(GOST) |
| TP321 UNS S32100 321 S32100 |
JIS G4304 | X10CrNiTi18-9 (DIN) 1.4541 (EN) |
06Cr18Ni11Ti(NEW) 1Cr18Ni9Ti (Old) S32168 |
X6CrNiTi18-10 | 304S12 321S20 (historical) |
12Х18Н10Т |
ASTM A312/A312M Standard Cold Machining Size Deviation Permitted
| ASTM A312/A312M-09 Standard Permitted Tolerance of WT and OD | |||||
|---|---|---|---|---|---|
| Nominal Outside Diameter | Allowable deviation | Nominal wall thickness | Allowable deviation | ||
| 1/8”—1 1/2“ | (10.29—48.26) | +0.4 -0.8 | 1/8”—1 1/2“ | (10.29-73.03) all of t | +20 -12.5 |
| >1 1/2“—4” | (48.26—114.3) | ±0.8 | 3“—18” | (88.9-457.2) t/D=5% | +22.5 -12.5 |
| >4”—8" | (114.3—219.08) | +1.6 -0.8 | 3“—18” | (88.9-457.2) t/D>5% | +15 -12.5 |
| >8“—18" | (219.08—457.2) | +2.4 -0.8 | ≥20" | =508 t of wld pipe | +17.5 -12.5 |
| >18”—26“ | (457.2—660.4) | +3.2 -0.8 | ≥20" | =508 t/D=5% | +22.5 -12.5 |
| >26”—34” | (660.4—863.6) | +4.0 -0.8 | ≥20" | =508 t/D>5% | +15 -12.5 |
| >34“—48" | (863.6—1219.2) | +4.8 -0.8 | |||
| Thin wall pipe (t/D=3%) ovality condition: Any cross section in a steel pipe Dmax Dmin=1.5%nominal, and (Dmax Dmin)/ 2 conforms to the stipulated diameter tolerance range. | |||||
Comparison Table Of American Standard Dimensions - (ANSI B36.19 & ANSI B36.10)
| OD DN | IN | OD MM | ANSI B36.19 | ANSI B36.10 | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Nominal diameter in inches | ||||||||||||||||||||
| 5s | 10s | Sched.40s | Sched.40 | Sched.80s | Sched.80 | 10 | 20 | 30 | Standard | |||||||||||
| mm | Kg/m | mm | Kg/m | mm | Kg/m | mm | mm | Kg/m | mm | mm | Kg/m | mm | Kg/m | mm | Kg/m | mm | Kg/m | |||
| 6 | 1/8" | 10.29 | - | - | 1.24 | 0.281 | 1.73 | 371 | 1.73 | 2.41 | 0.467 | 2.41 | - | - | - | - | - | - | 1.73 | 0.371 |
| 8 | 1/4" | 13.72 | - | - | 1.65 | 0.499 | 2.24 | 0.644 | 2 | 3.02 | 0.809 | 3.02 | - | - | - | - | - | - | 2.24 | 0.644 |
| 10 | 3/8" | 17.14 | - | - | 1.65 | 0.64 | 2.31 | 0.858 | 2.31 | 3.2 | 1.118 | 3.2 | - | - | - | - | - | - | 2.31 | 0.858 |
| 15 | 1/2" | 21.34 | 1.65 | 0.814 | 2.11 | 1.016 | 2.77 | 1.26 | 2.77 | 3.73 | 1.62 | 3.73 | - | - | - | - | - | - | 2.77 | 1.26 |
| 20 | 3/4" | 26.67 | 1.65 | 1.034 | 2.11 | 1.298 | 2.87 | 1.68 | 2.87 | 3.91 | 2.19 | 3.91 | - | - | - | - | - | - | 2.87 | 1.68 |
| 25 | 1" | 33.4 | 1.65 | 1.312 | 2.77 | 2.125 | 3.38 | 2.5 | 3.38 | 4.55 | 3.23 | 4.55 | - | - | - | - | - | - | 3.36 | 2.5 |
| 32 | 1 1/4" | 42.16 | 1.65 | 1.674 | 2.77 | 2.732 | 3.56 | 3.38 | 3.56 | 4.85 | 4.46 | 4.85 | - | - | - | - | - | - | 3.56 | 3.38 |
| 40 | 1 1/2" | 48.26 | 1.65 | 1.926 | 2.77 | 3.155 | 3.68 | 4.05 | 3.68 | 5.08 | 5.4 | 5.08 | - | - | - | - | - | - | 3.68 | 4.05 |
| 50 | 2" | 60.32 | 1.65 | 2.424 | 2.77 | 3.992 | 3.91 | 5.43 | 3.91 | 5.54 | 7.47 | 5.54 | - | - | - | - | - | - | 3.91 | 5.43 |
| 65 | 2 1/2" | 73.02 | 2.11 | 3.747 | 3.05 | 5.345 | 5.16 | 8.62 | 5.16 | 7.01 | 11.4 | 7.01 | - | - | - | - | - | - | 5.16 | 8.62 |
| 80 | 3" | 88.9 | 2.11 | 4.585 | 3.05 | 6.557 | 5.49 | 11.28 | 5.49 | 7.62 | 15.25 | 7.62 | - | - | - | - | - | - | 5.49 | 11.28 |
| 90 | 3 1/2" | 101.6 | 2.11 | 5.272 | 3.05 | 7.526 | 5.74 | 13.56 | 5.74 | 8.08 | 18.62 | 8.08 | - | - | - | - | - | - | 5.74 | 13.56 |
| 100 | 4" | 114.3 | 2.11 | 5.945 | 3.05 | 8.496 | 6.02 | 16.06 | 6.02 | 8.56 | 22.29 | 8.56 | - | - | - | - | - | - | 6.02 | 16.06 |
| 125 | 5" | 141.3 | 2.77 | 9.639 | 3.4 | 11.74 | 6.55 | 21.76 | 6.55 | 9.52 | 30.92 | 9.52 | - | - | - | - | - | - | 6.55 | 21.76 |
| 150 | 6" | 168.28 | 2.77 | 11.514 | 3.4 | 14.037 | 7.11 | 28.23 | 7.11 | 10.97 | 42.52 | 10.97 | - | - | - | - | - | - | 7.11 | 28.23 |
| 200 | 8" | 219.08 | 2.77 | 15.049 | 3.76 | 20.334 | 8.18 | 42.49 | 8.18 | 12.7 | 64.57 | 12.7 | - | - | 6.35 | 33.28 | 7.04 | 36.8 | 8.18 | 42.4 |
| 250 | 10" | 273.05 | 3.4 | 23.028 | 4.19 | 28.29 | 9.27 | 60.24 | 9.27 | 12.7 | 81.46 | 15.09 | - | - | 6.35 | 41.7 | 7.8 | 51 | 9.27 | 60.24 |
| 300 | 12" | 323.85 | 3.96 | 31.806 | 4.57 | 36.633 | 9.52 | 73.76 | 10.31 | 12.7 | 97.36 | 17.48 | - | - | 6.35 | 49.68 | 8.38 | 65.14 | 9.52 | 73.76 |
| 350 | 14" | 355.6 | 3.98 | 34.99 | 4.78 | 42.102 | 9.52 | - | 11.13 | - | - | 19.05 | 6.35 | 54.63 | 7.92 | 67.98 | 9.52 | 81.21 | 9.52 | 81.21 |
| 400 | 16" | 406.4 | 4.19 | 42.35 | 4.78 | 48.22 | 9.52 | - | 12.7 | - | - | 21.44 | 6.35 | 62.58 | 7.92 | 77.9 | 9.52 | 93.13 | 9.52 | 93.18 |
| 450 | 18" | 457.2 | 4.19 | 47.7 | 4.78 | 54.3 | 9.52 | - | 14.27 | - | - | 23.82 | 6.35 | 70.5 | 7.92 | 87.8 | 11.13 | 122.12 | 9.52 | 105.05 |
| 500 | 20" | 508 | 4.77 | 60.32 | 5.54 | 69.766 | 9.52 | - | 15.09 | - | - | 26.19 | 6.35 | 78.47 | 9.52 | 116.97 | 12.7 | 155 | 9.52 | 116.97 |
| 550 | 22" | 558.8 | 4.77 | - | 5.54 | - | 9.52 | - | - | - | - | 28.58 | 6.35 | 86.42 | 9.52 | 128.89 | 12.7 | 170.86 | 9.52 | 128.89 |
| 600 | 24" | 609.6 | 5.54 | 84.1 | 6.35 | 96.215 | 9.52 | - | 17.48 | - | - | 30.96 | 6.35 | 96.215 | 9.52 | 140.8 | 14.7 | 209.54 | 9.52 | 140.81 |
| 650 | 26" | 660.4 | - | - | - | - | 9.52 | - | - | - | - | - | 7.92 | 127.58 | 12.7 | 202.65 | - | - | 9.52 | 152.73 |
| 700 | 28" | 711.2 | - | - | - | - | 9.52 | - | - | - | - | - | 7.92 | 137.52 | 12.7 | 218.54 | 15.88 | 271.94 | 9.52 | 164.65 |
| 750 | 30" | 762 | 6.35 | 120.59 | 7.92 | 147.45 | 9.52 | - | - | - | - | - | 7.92 | 147.45 | 12.7 | 234.44 | 15.88 | 291.81 | 9.52 | 176.57 |
| 800 | 32" | 812 | - | - | - | - | 9.52 | - | 17.48 | - | - | - | 7.92 | 157.39 | 12.7 | 250.33 | 15.88 | 311.67 | 9.52 | 188.5 |
| 850 | 34" | 863.6 | - | - | - | - | 9.52 | - | 17.48 | - | - | - | 7.92 | 167.32 | 12.7 | 266.22 | 15.88 | 331.54 | 9.52 | 200.42 |
| 900 | 36" | 914.4 | - | - | - | - | 9.52 | - | 19.05 | - | - | - | 7.92 | 177.26 | 12.7 | 282.18 | 15.88 | 351.41 | 9.52 | 212.34 |
Frequently Asked Questions (FAQ)
What is TP321 stainless steel and how is it stabilized?
TP321 is a titanium-stabilized austenitic stainless steel. The addition of titanium (Ti) prevents carbide precipitation during welding or prolonged exposure to high temperatures (450°C–850°C), making it highly resistant to intergranular corrosion.
What are the main applications for ASTM A312 TP321?
Due to its high-temperature stability, it is widely used in the chemical & petrochemical industries, oil & gas, fertilizer plants, automotive & aerospace, power generation, food processing, and pharmaceutical sectors.
What is the maximum service temperature for TP321?
TP321 maintains mechanical integrity and oxidation resistance at temperatures up to 870°C (1600°F), which makes it suitable for exhaust systems, boilers, and heat exchangers.
What are the mechanical properties of TP321?
According to standard mechanical testing parameters, TP321 has a minimum tensile strength of 515 MPa, a minimum yield strength (0.2% Proof) of 205 MPa, and a maximum Brinell hardness (HB) of 220.
What are the equivalent grades of TP321 across international standards?
Equivalent grades include UNS S32100 (USA), JIS G4304 (Japan), 1.4541 / X10CrNiTi18-9 (Germany/EN), 06Cr18Ni11Ti / S32168 (China), and 12Х18Н10Т (Russia).
What testing and inspections are standard for TP321 pipes?
TP321 pipes typically undergo 100% PMI testing, are supplied with an EN10204.3.1B Mill Test Certificate, and third-party inspection is accepted to guarantee quality.







