We offer ASTM A312 TP304 seamless stainless steel pipe in many years experiences, ASTM A312 specification with TP304 grade, pipe sizes and dimensions in NPS range from 1/8 inch to 30 inch, wall thickness in Schedule range from SCH 5 to Sch 160.
ASTM A312 TP304 seamless pipe is used for various applications, which require pipe have high strength and excellent corrosion resistance in harsh environment, TP304 stainless steel is a ideal grade to balance cost and usage, its properties enable to meet the most conditions.
ASTM A312 TP304 Seamless Stainless Steel Pipe Specifications
| Specification | ASTM A312 |
|---|---|
| Grade | TP304 |
| Pipe form | Round pipe |
| Outside diameter | NPS: 1/8″ – 30″ 10.3 – 762 mm DN 6 – DN 750 |
| Schedule | Sch 5s, Sch 10s, Sch 40s, Sch 80s |
| Finishes | Annealing pickling |
| Pipe ends | Plain ends, bevelled ends |
ASTM A312 Standard Seamless Pipe
ASTM A312 Standard is seamless pipe specification, also covering welded pipe, seamless pipe is used for high temperature and general service, manufacturing seamless pipe have no any welding process, that is why seamless pipe provides better properties than welded pipe.
ASTM A312 TP 304 Stainless Steel
ASTM A312 TP 304 Stainless Steel is the most used 300 series stainless steel grade, it combines of sufficient Chrome and Nickel contents to possess excellent properties, ASTM A312 TP 304 has good corrosion resistance, good formability and good weldability to meet various applications.
Table 1, ASTM A312 TP304 stainless steel chemical composition.
| Grade | C | Mn | P | S | Si | Ni | Cr | Fe |
|---|---|---|---|---|---|---|---|---|
| TP304 | 0.08 | 2.00 | 0.045 | 0.030 | 1.0 | 8-11 | 18-20 | Bal. |
Table 2, ASTM A312 TP304 stainless steel mechanical properties:
| Tensile strength(Mpa) Max | Yield point(Mpa) Max | Elongation(%) | Hardness (HRB) Max | |
|---|---|---|---|---|
| TP304 | 515 | 205 | 35 | 92 |
TP304 stainless steel EN equivalent is 1.4301.
Manufacturing ASTM A312 TP304 Seamless Stainless Steel Pipe
Billet
Seamless pipe start from steel billet, billet is semi finished product, it should be inspected prior to processing, choosing superior quality material, and proper billet sizes, common sizes range from 50 – 280, special size for special seamless pipe size can be offered.
Cold Rolling, Cold Drawing
To achieve precise seamless pipe, cold rolling and cold drawing process reduce outside diameter and wall thickness, gradually form required seamless pipe.
Heat Treatment
All the seamless pipes should be heat treated under required temperature, after cold worked, residual stress have been caused, and potential impurities may be occur, heat treatment rebuild alloy structure, then obtain original properties. TP304 stainless steel minimum annealing temperature should be 1040 degree C.
Quality Control
Tolerance: ASTM A312 specification specified outside diameter and wall thickness limitations, OD tolerance conform to ASTM A999.
| OD | Tolerance | WTH（mm) |
|---|---|---|
| 10.3-48.3 | +0.40/-0.80 | +/-12.5%t |
| ＞48.3-114.3 | +0.80/-0.08 | |
| ＞114.3-219.1 | +1.60/-0.80 | |
| ＞219.1-457.2 | +2.40-0.80 | |
| ＞457.2-660.4 | +3.20/-0.80 | |
| ＞660.4-864 | +4.00/-0.08 | |
| ＞864-1219.2 | +4.80/-0.08 |
Standard Testing And Inspection
- Visual inspection
- Mechanical Tests
- Hydrostatic test
- Flattening Test
- PMI
- Grain Size
Dimensions Of ASTM A312 Seamless Stainless Steel Pipe
| NPS Designator | Outside Diameter | Nominal Wall Thickness | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| in. | mm | Schedule 5S | Schedule 10S | Schedule 40S | Schedule 80S | |||||
| in. | mm | in. | mm | in. | mm | in. | mm | |||
| 1⁄8 | 0.405 | 10.29 | … | … | 0.049 | 1.24 | 0.068 | 1.73 | 0.095 | 2.41 |
| 1⁄4 | 0.540 | 13.72 | … | … | 0.065 | 1.65 | 0.088 | 2.24 | 0.119 | 3.02 |
| 3⁄8 | 0.675 | 17.15 | … | … | 0.065 | 1.65 | 0.091 | 2.31 | 0.126 | 3.20 |
| 1⁄2 | 0.840 | 21.34 | 0.065 | 1.65 | 0.083 | 2.11 | 0.109 | 2.77 | 0.147 | 3.73 |
| 3⁄4 | 1.050 | 26.67 | 0.065 | 1.65 | 0.083 | 2.11 | 0.113 | 2.87 | 0.154 | 3.91 |
| 1.0 | 1.315 | 33.40 | 0.065 | 1.65 | 0.109 | 2.77 | 0.133 | 3.38 | 0.179 | 4.55 |
| 1-1⁄4 | 1.660 | 42.16 | 0.065 | 1.65 | 0.109 | 2.77 | 0.140 | 3.56 | 0.191 | 4.85 |
| 11⁄2 | 1.900 | 48.26 | 0.065 | 1.65 | 0.109 | 2.77 | 0.145 | 3.68 | 0.200 | 5.08 |
| 2 | 2.375 | 60.33 | 0.065 | 1.65 | 0.109 | 2.77 | 0.154 | 3.91 | 0.218 | 5.54 |
| 2-1⁄2 | 2.875 | 73.03 | 0.083 | 2.11 | 0.120 | 3.05 | 0.203 | 5.16 | 0.276 | 7.01 |
| 3 | 3.500 | 88.90 | 0.083 | 2.11 | 0.120 | 3.05 | 0.216 | 5.49 | 0.300 | 7.62 |
| 3-1⁄2 | 4.000 | 101.60 | 0.083 | 2.11 | 0.120 | 3.05 | 0.226 | 5.74 | 0.318 | 8.08 |
| 4 | 4.500 | 114.30 | 0.083 | 2.11 | 0.120 | 3.05 | 0.237 | 6.02 | 0.337 | 8.56 |
| 5 | 5.563 | 141.30 | 0.109 | 2.77 | 0.134 | 3.40 | 0.258 | 6.55 | 0.375 | 9.52 |
| 6 | 6.625 | 168.28 | 0.109 | 2.77 | 0.134 | 3.40 | 0.280 | 7.11 | 0.432 | 10.97 |
| 8 | 8.625 | 219.08 | 0.109 | 2.77 | 0.148 | 3.76 | 0.322 | 8.18 | 0.500 | 12.70 |
| 10 | 10.750 | 273.05 | 0.134 | 3.40 | 0.165 | 4.19 | 0.365 | 9.27 | 0.500 | 12.70 |
| 12 | 12.750 | 323.85 | 0.156 | 3.96 | 0.180 | 4.57 | 0.375 | 9.52 | 0.500 | 12.70 |
| 14 | 14.000 | 355.60 | 0.156 | 3.96 | 0.188 | 4.78 | … | … | … | … |
| 16 | 16.000 | 406.40 | 0.165 | 4.19 | 0.188 | 4.78 | … | … | … | … |
| 18 | 18.000 | 457.20 | 0.165 | 4.19 | 0.188 | 4.78 | … | … | … | … |
| 20 | 20.000 | 508.00 | 0.188 | 4.78 | 0.218 | 5.54 | … | … | … | … |
| 22 | 22.000 | 558.80 | 0.188 | 4.78 | 0.218 | 5.54 | … | … | … | … |
| 24 | 24.000 | 609.60 | 0.218 | 5.54 | 0.250 | 6.35 | … | … | … | … |
| 30 | 30.000 | 762.00 | 0.250 | 6.35 | 0.312 | 7.92 | … | … | … | … |
