-
Products
- VALVES
- FITTINGS
- FORGED FLANGE
- SS WELDED PIPE&TUBE
- SS SMLS TUBE
-
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
TP321 Stainless Steel Seamless Pipes from China - Reliable Suppliers & 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
Standard
ASTM A312/A312M
O.D Range
1/8" NB to 32" NB (10.29mm - 812.80mm) (Customization Available)
W.T Range
SCH 10S, SCH 40S, SCH 80S, SCH160, SCH XXS (Customization Available)
End Connections
Plain End, Beveled End, Threaded
Processing Methods
Cut-to-length, Polishing
Inspection & Testing
100% PMI Tested, EN10204 3.1B Mill Test Certificate, Third Party Inspection Accepted
Delivery Conditions
Cold Drawn, Annealed and Pickled / Polished / Bright Annealed / Sand blasting / Shot Blasting
Marking Info
Standard, Grade, OD, Thickness, Length, Heat No. (Or as per customer's request)
Packaging
Packed in Wooden Boxes, Plywood Cases, Steel Strips Bundled, or as per Customer's Request
Customization
Sizes and Specifications other than standard can be customized on request.
Applications
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
| 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 | ||||
| TP321 | 515 | 205 | 35 | 100 | 220 |
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
| Nominal Outside Diameter Tolerances | Nominal Wall Thickness Tolerances | ||||
|---|---|---|---|---|---|
| OD (inch) | OD (mm) | Allowable Deviation (mm) | OD Range (inch) | OD Range (mm) / Ratio | 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 t) | +20.0 / -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%) | +15.0 / -12.5 |
| >8" - 18" | 219.08 - 457.2 | +2.4 / -0.8 | ≥20" | ≥508 (welded 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%) | +15.0 / -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% of 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 | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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 | 0.371 | 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 | 2.24 | 3.02 | 0.809 | 3.02 | - | - | - | - | - | - | 2.24 | 0.644 |
| 10 | 3/8" | 17.14 | - | - | 1.65 | 0.640 | 2.31 | 0.858 | 2.31 | 3.20 | 1.118 | 3.20 | - | - | - | - | - | - | 2.31 | 0.858 |
| 15 | 1/2" | 21.34 | 1.65 | 0.814 | 2.11 | 1.016 | 2.77 | 1.260 | 2.77 | 3.73 | 1.620 | 3.73 | - | - | - | - | - | - | 2.77 | 1.260 |
| 20 | 3/4" | 26.67 | 1.65 | 1.034 | 2.11 | 1.298 | 2.87 | 1.680 | 2.87 | 3.91 | 2.190 | 3.91 | - | - | - | - | - | - | 2.87 | 1.680 |
| 25 | 1" | 33.40 | 1.65 | 1.312 | 2.77 | 2.125 | 3.38 | 2.500 | 3.38 | 4.55 | 3.230 | 4.55 | - | - | - | - | - | - | 3.38 | 2.500 |
| 32 | 1 1/4" | 42.16 | 1.65 | 1.674 | 2.77 | 2.732 | 3.56 | 3.380 | 3.56 | 4.85 | 4.460 | 4.85 | - | - | - | - | - | - | 3.56 | 3.380 |
| 40 | 1 1/2" | 48.26 | 1.65 | 1.926 | 2.77 | 3.155 | 3.68 | 4.050 | 3.68 | 5.08 | 5.400 | 5.08 | - | - | - | - | - | - | 3.68 | 4.050 |
| 50 | 2" | 60.32 | 1.65 | 2.424 | 2.77 | 3.992 | 3.91 | 5.430 | 3.91 | 5.54 | 7.470 | 5.54 | - | - | - | - | - | - | 3.91 | 5.430 |
| 65 | 2 1/2" | 73.02 | 2.11 | 3.747 | 3.05 | 5.345 | 5.16 | 8.620 | 5.16 | 7.01 | 11.400 | 7.01 | - | - | - | - | - | - | 5.16 | 8.620 |
| 80 | 3" | 88.90 | 2.11 | 4.585 | 3.05 | 6.557 | 5.49 | 11.280 | 5.49 | 7.62 | 15.250 | 7.62 | - | - | - | - | - | - | 5.49 | 11.280 |
| 90 | 3 1/2" | 101.60 | 2.11 | 5.272 | 3.05 | 7.526 | 5.74 | 13.560 | 5.74 | 8.08 | 18.620 | 8.08 | - | - | - | - | - | - | 5.74 | 13.560 |
| 100 | 4" | 114.30 | 2.11 | 5.945 | 3.05 | 8.496 | 6.02 | 16.060 | 6.02 | 8.56 | 22.290 | 8.56 | - | - | - | - | - | - | 6.02 | 16.060 |
| 125 | 5" | 141.30 | 2.77 | 9.639 | 3.40 | 11.740 | 6.55 | 21.760 | 6.55 | 9.52 | 30.920 | 9.52 | - | - | - | - | - | - | 6.55 | 21.760 |
| 150 | 6" | 168.28 | 2.77 | 11.514 | 3.40 | 14.037 | 7.11 | 28.230 | 7.11 | 10.97 | 42.520 | 10.97 | - | - | - | - | - | - | 7.11 | 28.230 |
| 200 | 8" | 219.08 | 2.77 | 15.049 | 3.76 | 20.334 | 8.18 | 42.490 | 8.18 | 12.70 | 64.570 | 12.70 | - | - | 6.35 | 33.280 | 7.04 | 36.800 | 8.18 | 42.400 |
| 250 | 10" | 273.05 | 3.40 | 23.028 | 4.19 | 28.290 | 9.27 | 60.240 | 9.27 | 12.70 | 81.460 | 15.09 | - | - | 6.35 | 41.700 | 7.80 | 51.000 | 9.27 | 60.240 |
| 300 | 12" | 323.85 | 3.96 | 31.806 | 4.57 | 36.633 | 9.52 | 73.760 | 10.31 | 12.70 | 97.360 | 17.48 | - | - | 6.35 | 49.680 | 8.38 | 65.140 | 9.52 | 73.760 |
| 350 | 14" | 355.60 | 3.98 | 34.990 | 4.78 | 42.102 | 9.52 | - | 11.13 | - | - | 19.05 | 6.35 | 54.630 | 7.92 | 67.980 | 9.52 | 81.210 | 9.52 | 81.210 |
| 400 | 16" | 406.40 | 4.19 | 42.350 | 4.78 | 48.220 | 9.52 | - | 12.70 | - | - | 21.44 | 6.35 | 62.580 | 7.92 | 77.900 | 9.52 | 93.130 | 9.52 | 93.180 |
| 450 | 18" | 457.20 | 4.19 | 47.700 | 4.78 | 54.300 | 9.52 | - | 14.27 | - | - | 23.82 | 6.35 | 70.500 | 7.92 | 87.800 | 11.13 | 122.120 | 9.52 | 105.050 |
| 500 | 20" | 508.00 | 4.77 | 60.320 | 5.54 | 69.766 | 9.52 | - | 15.09 | - | - | 26.19 | 6.35 | 78.470 | 9.52 | 116.970 | 12.70 | 155.000 | 9.52 | 116.970 |
| 550 | 22" | 558.80 | 4.77 | - | 5.54 | - | 9.52 | - | - | - | - | 28.58 | 6.35 | 86.420 | 9.52 | 128.890 | 12.70 | 170.860 | 9.52 | 128.890 |
| 600 | 24" | 609.60 | 5.54 | 84.100 | 6.35 | 96.215 | 9.52 | - | 17.48 | - | - | 30.96 | 6.35 | 96.215 | 9.52 | 140.800 | 14.70 | 209.540 | 9.52 | 140.810 |
| 650 | 26" | 660.40 | - | - | - | - | 9.52 | - | - | - | - | - | 7.92 | 127.580 | 12.70 | 202.650 | - | - | 9.52 | 152.730 |
| 700 | 28" | 711.20 | - | - | - | - | 9.52 | - | - | - | - | - | 7.92 | 137.520 | 12.70 | 218.540 | 15.88 | 271.940 | 9.52 | 164.650 |
| 750 | 30" | 762.00 | 6.35 | 120.590 | 7.92 | 147.450 | 9.52 | - | - | - | - | - | 7.92 | 147.450 | 12.70 | 234.440 | 15.88 | 291.810 | 9.52 | 176.570 |
| 800 | 32" | 812.00 | - | - | - | - | 9.52 | - | 17.48 | - | - | - | 7.92 | 157.390 | 12.70 | 250.330 | 15.88 | 311.670 | 9.52 | 188.500 |
| 850 | 34" | 863.60 | - | - | - | - | 9.52 | - | 17.48 | - | - | - | 7.92 | 167.320 | 12.70 | 266.220 | 15.88 | 331.540 | 9.52 | 200.420 |
| 900 | 36" | 914.40 | - | - | - | - | 9.52 | - | 19.05 | - | - | - | 7.92 | 177.260 | 12.70 | 282.180 | 15.88 | 351.410 | 9.52 | 212.340 |
Frequently Asked Questions (FAQ)
Q
What is TP321 stainless steel and what makes it unique?
TP321 is a titanium-stabilized austenitic stainless steel closely related to 304/304L. It is uniquely designed with the addition of titanium (Ti) to mitigate carbide precipitation and provide enhanced resistance to intergranular corrosion, especially in high-temperature environments.
Q
What is the maximum operating temperature for TP321 stainless steel?
TP321 exhibits high-temperature stability, maintaining its mechanical integrity and oxidation resistance at temperatures up to 870°C (1600°F). This makes it highly suitable for boilers, heat exchangers, and exhaust systems.
Q
Under what standards are TP321 pipes manufactured?
TP321 stainless steel pipes are manufactured and inspected in accordance with the ASTM A312/A312M standard, which regulates dimensions, tolerances, chemical composition, and testing procedures.
Q
What are the equivalent international grades for ASTM A312 TP321?
Equivalent grades include UNS S32100 (USA), JIS G4304 (Japan), 1.4541 / X10CrNiTi18-9 (Germany/EN), 06Cr18Ni11Ti / S32168 (China), X6CrNiTi18-10 (ISO), and 12Х18Н10Т (Russia).
Q
What are the key mechanical properties of TP321?
TP321 features a minimum tensile strength of 515 MPa, a minimum 0.2% proof yield strength of 205 MPa, a minimum elongation of 35% in 50mm, and a maximum hardness of 100 HRB (Rockwell B) or 220 HB (Brinell).
Q
What industries commonly use TP321 stainless steel pipes?
Due to its superior corrosion and temperature resistance, TP321 is widely utilized in the Chemical & Petrochemical Industry, Oil & Gas, Fertilizer Plants, Automotive & Aerospace, Power Generation, Food Processing, Pharmaceutical & Biotechnology, Pulp & Paper, and Construction & Architecture.