ASTM A312 TP304 Seamless Stainless Steel Pipe

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.

Basic specifications
Specification ASTM A312
Pipe form Round pipe
Outside diameter NPS: 1/8″ – 30″
10.3 – 762 mm
DN 6 – DN 750
Schedule Sch 5, Sch 10s, Sch 40s, Sch 80s
Gr TP304
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.

TP304 Stainless Steel

TP304 grade is the most used 300 series stainless steel, TP304 contains sufficient Chrome and Nickel content, the result is it has excellent properties to meet many requirements, these properties include good corrosion resistance, good formability, and good weldability.

Table 1, 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, 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

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