A333 Gr. 6 Pipe MAWP Calculator ASTM A333-6 Steel Pipe SMLS
Material Properties Description
ASTM A333-6 Steel Pipe SMLS
Min Design Temperature
-50 °F
Y Coefficient
Ref 3 — Ferritic steels
Maximum Allowable Working Pressure (psig) Sch STD Sch XS Sch 160
NPS OD (in) 100 °F 200 °F 300 °F 400 °F 500 °F 600 °F 700 °F 800 °F 1/8 0.405 6,659 6,659 6,659 6,626 6,326 5,960 5,560 3,796 1/4 0.54 6,438 6,438 6,438 6,406 6,116 5,762 5,376 3,670 3/8 0.675 5,210 5,210 5,210 5,184 4,950 4,663 4,351 2,970 1/2 0.84 4,995 4,995 4,995 4,970 4,746 4,471 4,171 2,847 3/4 1.05 4,074 4,074 4,074 4,053 3,870 3,646 3,401 2,322 1 1.315 3,810 3,810 3,810 3,791 3,619 3,410 3,181 2,171 1 1/4 1.66 3,137 3,137 3,137 3,121 2,980 2,808 2,619 1,788 1 1/2 1.9 2,822 2,822 2,822 2,808 2,681 2,526 2,356 1,608 2 2.375 2,377 2,377 2,377 2,365 2,259 2,128 1,985 1,355 2 1/2 2.875 2,600 2,600 2,600 2,587 2,470 2,327 2,171 1,482 3 3.5 2,258 2,258 2,258 2,246 2,145 2,020 1,885 1,287 3.5 4 2,059 2,059 2,059 2,049 1,956 1,843 1,719 1,174 4 4.5 1,914 1,914 1,914 1,904 1,818 1,713 1,598 1,091 5 5.563 1,678 1,678 1,678 1,669 1,594 1,502 1,401 956 6 6.625 1,524 1,524 1,524 1,517 1,448 1,364 1,273 869 7 7.625 1,421 1,421 1,421 1,414 1,350 1,272 1,186 810 8 8.625 1,342 1,342 1,342 1,335 1,275 1,201 1,120 765 9 9.625 1,275 1,275 1,275 1,269 1,212 1,141 1,065 727 10 10.75 1,217 1,217 1,217 1,211 1,156 1,089 1,016 694 12 12.75 1,051 1,051 1,051 1,046 998 941 878 599 14 14 955 955 955 951 908 855 798 545 16 16 834 834 834 830 792 746 696 475 18 18 740 740 740 736 703 662 618 422 20 20 665 665 665 662 632 595 555 379 22 22 604 604 604 601 574 540 504 344 24 24 553 553 553 550 525 495 462 315 26 26 510 510 510 507 484 456 426 291 28 28 473 473 473 471 450 424 395 270 30 30 441 441 441 439 419 395 369 252 36 36 367 367 367 365 349 329 307 209 42 42 314 314 314 313 299 281 263 179 44 44 300 300 300 299 285 269 251 171 46 46 287 287 287 286 273 257 240 164 48 48 275 275 275 274 261 246 230 157
Allowable Stress vs Temperature 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 1000 1100 Temperature (°F) 0 5 10 15 20 Allowable Stress (ksi) Disclaimer: This calculator is for guidance only. Results are based on ASME B31.3-2024 allowable stresses for seamless pipe (Ej=1.0, W=1.0). Always verify against the current edition of the standard. The engineer of record is responsible for all design decisions.
References ASME B31.3-2024 — Process Piping, Table A-1 ASME B36.10M — Welded and Seamless Wrought Steel Pipe ASME B16.5-2020 — Pipe Flanges and Flanged Fittings 
