B729 N08020 Pipe MAWP Calculator ASTM B729 N08020 (020) Pipe or Tube SMLS, 35Ni-35Fe-20Cr-Cb, annealed
Material Properties Description
ASTM B729 N08020 (020) Pipe or Tube SMLS, 35Ni-35Fe-20Cr-Cb, annealed
Min Design Temperature
-325 °F
Y Coefficient
Ref 5 — Other ductile metals
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 7,758 7,758 7,758 7,758 7,758 7,758 7,758 7,558 1/4 0.54 7,500 7,500 7,500 7,500 7,500 7,500 7,500 7,307 3/8 0.675 6,070 6,070 6,070 6,070 6,070 6,070 6,070 5,914 1/2 0.84 5,820 5,820 5,820 5,820 5,820 5,820 5,820 5,670 3/4 1.05 4,746 4,746 4,746 4,746 4,746 4,746 4,746 4,623 1 1.315 4,438 4,438 4,438 4,438 4,438 4,438 4,438 4,324 1 1/4 1.66 3,655 3,655 3,655 3,655 3,655 3,655 3,655 3,560 1 1/2 1.9 3,287 3,287 3,287 3,287 3,287 3,287 3,287 3,203 2 2.375 2,770 2,770 2,770 2,770 2,770 2,770 2,770 2,698 2 1/2 2.875 3,029 3,029 3,029 3,029 3,029 3,029 3,029 2,951 3 3.5 2,630 2,630 2,630 2,630 2,630 2,630 2,630 2,562 3.5 4 2,399 2,399 2,399 2,399 2,399 2,399 2,399 2,337 4 4.5 2,230 2,230 2,230 2,230 2,230 2,230 2,230 2,172 5 5.563 1,955 1,955 1,955 1,955 1,955 1,955 1,955 1,904 6 6.625 1,776 1,776 1,776 1,776 1,776 1,776 1,776 1,730 7 7.625 1,655 1,655 1,655 1,655 1,655 1,655 1,655 1,613 8 8.625 1,563 1,563 1,563 1,563 1,563 1,563 1,563 1,523 9 9.625 1,486 1,486 1,486 1,486 1,486 1,486 1,486 1,448 10 10.75 1,418 1,418 1,418 1,418 1,418 1,418 1,418 1,382 12 12.75 1,224 1,224 1,224 1,224 1,224 1,224 1,224 1,193 14 14 1,113 1,113 1,113 1,113 1,113 1,113 1,113 1,084 16 16 972 972 972 972 972 972 972 947 18 18 862 862 862 862 862 862 862 840 20 20 775 775 775 775 775 775 775 755 22 22 703 703 703 703 703 703 703 685 24 24 644 644 644 644 644 644 644 628 26 26 594 594 594 594 594 594 594 579 28 28 551 551 551 551 551 551 551 537 30 30 514 514 514 514 514 514 514 501 36 36 428 428 428 428 428 428 428 417 42 42 366 366 366 366 366 366 366 357 44 44 350 350 350 350 350 350 350 341 46 46 334 334 334 334 334 334 334 326 48 48 320 320 320 320 320 320 320 312
Allowable Stress vs Temperature 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 Temperature (°F) 0 6 12 18 24 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 
