B729 N08020 Pipe MAWP Calculator

ASTM B729 N08020 (020) Pipe or Tube SMLS, 35Ni-35Fe-20Cr-Cb, annealed

Pressure Ratings > Pipe MAWP > B729 N08020

Material Properties

Specification

B729 N08020

Description

ASTM B729 N08020 (020) Pipe or Tube SMLS, 35Ni-35Fe-20Cr-Cb, annealed

Tensile Strength

80 ksi

Yield Strength

35 ksi

B16.5 Flange Group

Group 3.1 — Alloy 20 (35Ni-35Fe-20Cr-Cb)

Min Design Temperature

-325 °F

Y Coefficient

Ref 5 — Other ductile metals

Calculator Settings

Corrosion Allowance (in)

Mill Tolerance (%)

Units

Schedule Selection

STDXSXXS10S40S80S2030406080120140160

Temperature Selection

100 °F150 °F200 °F250 °F300 °F350 °F400 °F450 °F500 °F550 °F600 °F650 °F700 °F750 °F800 °F

Maximum Allowable Working Pressure (psig)

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

Custom Wall Thickness

NPS

Wall Thickness (in)

Allowable Stress vs Temperature

Matching Flange Group

Group 3.1 — Alloy 20 (35Ni-35Fe-20Cr-Cb)(A182/B462 N08020, A240/B463 N08020)

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.