Below burst pressure estimates are based on using Barlow's Formula.
* Barlow’s Formula is expressed as:
Tubing - (2 * MTS * t)/d for estimating theoretical burst pressure.
Pipe - (2 * MTS * t)/D for estimating theoretical burst pressure.
For tubing, outside diameter (D) can be substituted in the calculation for a more conservative value, however the use of inside diameter (d) has been proven valid. The end user should determine the appropriate working pressure and safety factor for the specific application given all relevant operating conditions.
MTS = Minimum tensile strength (psi); MYS = Minimum yield strength (psi); t = Nominal wall thickness (inches); d = Nominal inside diameter (inches);
D = Nominal outside diameter (inches); Working pressure = 1/4 of theoretical burst pressure
Pressure ratings are based on 100° F operating environment only
** Theoretical yield pressure is the point of permanent deformation and calculated by substituting the MYS value in the equation.
*** Collapse pressure estimate shown is per API 5C3 calculation. Formula: (2 * MYS * (D/t - 1)) / (D/t)2
ASTM A312 PIPE PRESSURE RATINGS
NPS Oustide Diameter
Sched
Actual O.D. (in)
Nom. Wall (in)
MYS (PSI)
MTS (PSI)
Theoretical Burst Pressure * (PSI)
Working Pressure (PSI) 25% of Burst
Theoretical Yield Point ** (PSI)
Collapse Pressure *** (PSI)
1/8"
10
0.405
0.049
30,000
75,000
18,148
4,537
7,259
6,381
1/8"
40
0.405
0.068
30,000
75,000
25,185
6,296
10,074
8,383
1/8"
80
0.405
0.095
30,000
75,000
35,185
8,796
14,074
10,773
1/4"
10
0.540
0.065
30,000
75,000
18,056
4,514
7,222
6,353
1/4"
40
0.540
0.088
30,000
75,000
24,444
6,111
9,778
8,184
1/4"
80
0.540
0.119
30,000
75,000
33,056
8,264
13,222
10,308
3/8"
10
0.678
0.065
30,000
75,000
14,381
3,595
5,752
5,201
3/8"
40
0.678
0.091
30,000
75,000
20,133
5,033
8,053
6,972
3/8"
80
0.678
0.126
30,000
75,000
27,876
6,969
11,150
9,078
1/2"
5
0.840
0.065
30,000
75,000
11,607
2,902
4,643
4,284
1/2"
10
0.840
0.083
30,000
75,000
14,821
3,705
5,929
5,343
1/2"
40
0.840
0.109
30,000
75,000
19,464
4,866
7,786
6,775
1/2"
80
0.840
0.147
30,000
75,000
26,250
6,563
10,500
8,663
3/4"
5
1.050
0.065
30,000
75,000
9,286
2,321
3,714
3,484
3/4"
10
1.050
0.083
30,000
75,000
11,857
2,964
4,743
4,368
3/4"
40
1.050
0.113
30,000
75,000
16,143
4,036
6,457
5,762
3/4"
80
1.050
0.154
30,000
75,000
22,000
5,500
8,800
7,509
1"
5
1.315
0.065
30,000
75,000
7,414
1,854
2,966
2,819
1"
10
1.315
0.109
30,000
75,000
12,433
3,108
4,973
4,561
1"
40
1.315
0.133
30,000
75,000
15,171
3,793
6,068
5,455
1"
80
1.315
0.179
30,000
75,000
20,418
5,105
8,167
7,056
1 1/4"
5
1.660
0.065
30,000
75,000
5,873
1,468
2,349
2,257
1 1/4"
10
1.660
0.109
30,000
75,000
9,849
2,462
3,940
3,681
1 1/4"
40
1.660
0.14
30,000
75,000
12,651
3,163
5,060
4,633
1 1/4"
80
1.660
0.191
30,000
75,000
17,259
4,315
6,904
6,109
1 1/2"
5
1.900
0.065
30,000
75,000
5,132
1,283
2,053
1,982
1 1/2"
10
1.900
0.109
30,000
75,000
8,605
2,151
3,442
3,245
1 1/2"
40
1.900
0.145
30,000
75,000
11,447
2,862
4,579
4,230
1 1/2"
80
1.900
0.2
30,000
75,000
15,789
3,947
6,316
5,651
2"
5
2.375
0.065
30,000
75,000
4,105
1,026
1,642
1,597
2"
10
2.375
0.109
30,000
75,000
6,884
1,721
2,754
2,627
2"
40
2.375
0.154
30,000
75,000
9,726
2,432
3,891
3,638
2"
80
2.375
0.218
30,000
75,000
13,768
3,442
5,507
5,002
TUBE PRESSURE RATINGS FOR ASTM - A269-A249 - 304L-316L
OD inches
Ave. Wall inches
Min Yield Strength (PSI)
Min Tensile Strength (PSI)
Theoretical Burst Pressure * (PSI)
Working Pressure (PSI) 25% of Burst
Theoretical Yield Point ** (PSI)
Collapse Pressure *** (PSI)
0.25
0.020
30,000
75,000
14,286
3,571
5,714
4,416
0.25
0.028
30,000
75,000
21,649
5,412
8,660
5,967
0.25
0.035
30,000
75,000
29,167
7,292
11,667
7,224
0.25
0.049
30,000
75,000
48,355
12,089
19,342
9,455
0.25
0.065
30,000
75,000
81,250
20,313
32,500
11,544
0.375
0.020
30,000
75,000
8,955
2,239
3,582
3,029
0.375
0.028
30,000
75,000
13,166
3,292
5,266
4,145
0.375
0.035
30,000
75,000
17,213
4,303
6,885
5,077
0.375
0.049
30,000
75,000
26,534
6,634
10,614
6,816
0.375
0.065
30,000
75,000
39,796
9,949
15,918
8,597
0.5
0.020
30,000
75,000
6,522
1,630
2,609
2,304
0.5
0.028
30,000
75,000
9,459
2,365
3,784
3,172
0.5
0.035
30,000
75,000
12,209
3,052
4,884
3,906
0.5
0.049
30,000
75,000
18,284
4,571
7,313
5,304
0.5
0.065
30,000
75,000
26,351
6,588
10,541
6,786
0.5
0.083
30,000
75,000
37,275
9,319
14,910
8,307
0.625
0.020
30,000
75,000
5,128
1,282
2,051
1,859
0.625
0.028
30,000
75,000
7,381
1,845
2,953
2,568
0.625
0.035
30,000
75,000
9,459
2,365
3,784
3,172
0.625
0.049
30,000
75,000
13,947
3,487
5,579
4,335
0.625
0.065
30,000
75,000
19,697
4,924
7,879
5,591
0.625
0.083
30,000
75,000
27,124
6,781
10,850
6,910
0.625
0.095
30,000
75,000
32,759
8,190
13,103
7,734
0.625
0.109
30,000
75,000
40,172
10,043
16,069
8,639
0.75
0.028
30,000
75,000
6,052
1,513
2,421
2,156
0.75
0.035
30,000
75,000
7,721
1,930
3,088
2,669
0.75
0.049
30,000
75,000
11,273
2,818
4,509
3,664
0.75
0.065
30,000
75,000
15,726
3,931
6,290
4,749
0.75
0.083
30,000
75,000
21,318
5,330
8,527
5,905
0.75
0.095
30,000
75,000
25,446
6,362
10,179
6,637
0.75
0.109
30,000
75,000
30,733
7,683
12,293
7,453
0.75
0.120
30,000
75,000
35,294
8,824
14,118
8,064
0.875
0.020
30,000
75,000
3,593
898
1,437
1,340
0.875
0.028
30,000
75,000
5,128
1,282
2,051
1,859
0.875
0.035
30,000
75,000
6,522
1,630
2,609
2,304
0.875
0.049
30,000
75,000
9,459
2,365
3,784
3,172
0.875
0.065
30,000
75,000
13,087
3,272
5,235
4,126
0.875
0.083
30,000
75,000
17,560
4,390
7,024
5,152
0.875
0.095
30,000
75,000
20,803
5,201
8,321
5,807
0.875
0.109
30,000
75,000
24,886
6,221
9,954
6,543
0.875
0.120
30,000
75,000
28,346
7,087
11,339
7,100
1
0.028
30,000
75,000
4,449
1,112
1,780
1,633
1
0.035
30,000
75,000
5,645
1,411
2,258
2,027
1
0.049
30,000
75,000
8,149
2,037
3,259
2,796
1
0.065
30,000
75,000
11,207
2,802
4,483
3,647
1
0.083
30,000
75,000
14,928
3,732
5,971
4,567
1
0.095
30,000
75,000
17,593
4,398
7,037
5,159
1
0.109
30,000
75,000
20,908
5,227
8,363
5,827
1
0.120
30,000
75,000
23,684
5,921
9,474
6,336
1
0.134
30,000
75,000
27,459
6,865
10,984
6,963
1.25
0.035
30,000
75,000
4,449
1,112
1,780
1,633
1.25
0.049
30,000
75,000
6,380
1,595
2,552
2,260
1.25
0.065
30,000
75,000
8,705
2,176
3,482
2,958
1.25
0.083
30,000
75,000
11,485
2,871
4,594
3,719
1.25
0.095
30,000
75,000
13,443
3,361
5,377
4,213
1.25
0.109
30,000
75,000
15,843
3,961
6,337
4,776
1.25
0.120
30,000
75,000
17,822
4,455
7,129
5,207
1.25
0.134
30,000
75,000
20,468
5,117
8,187
5,742
1.5
0.035
30,000
75,000
3,671
918
1,469
1,367
1.5
0.049
30,000
75,000
5,243
1,311
2,097
1,896
1.5
0.065
30,000
75,000
7,117
1,779
2,847
2,487
1.5
0.083
30,000
75,000
9,333
2,333
3,733
3,136
1.5
0.095
30,000
75,000
10,878
2,719
4,351
3,559
1.5
0.109
30,000
75,000
12,754
3,188
5,101
4,043
1.5
0.120
30,000
75,000
14,286
3,571
5,714
4,416
1.5
0.134
30,000
75,000
16,315
4,079
6,526
4,881
1.5
0.148
30,000
75,000
18,439
4,610
7,375
5,336
1.75
0.035
30,000
75,000
3,125
781
1,250
1,176
1.75
0.049
30,000
75,000
3,864
966
1,546
1,434
1.75
0.065
30,000
75,000
6,019
1,505
2,407
2,146
1.75
0.083
30,000
75,000
7,860
1,965
3,144
2,711
1.75
0.095
30,000
75,000
9,135
2,284
3,654
3,080
1.75
0.109
30,000
75,000
10,672
2,668
4,269
3,504
1.75
0.120
30,000
75,000
11,921
2,980
4,768
3,832
1.75
0.134
30,000
75,000
13,563
3,391
5,425
4,242
1.75
0.148
30,000
75,000
15,268
3,817
6,107
4,645
1.75
0.165
30,000
75,000
17,430
4,357
6,972
5,124
2
0.035
30,000
75,000
2,720
680
1,088
1,032
2
0.049
30,000
75,000
3,864
966
1,546
1,434
2
0.065
30,000
75,000
5,214
1,303
2,086
1,887
2
0.083
30,000
75,000
6,788
1,697
2,715
2,387
2
0.095
30,000
75,000
7,873
1,968
3,149
2,715
2
0.109
30,000
75,000
9,175
2,294
3,670
3,092
2
0.120
30,000
75,000
10,227
2,557
4,091
3,384
2
0.134
30,000
75,000
11,605
2,901
4,642
3,751
2
0.148
30,000
75,000
13,028
3,257
5,211
4,111
2
0.165
30,000
75,000
14,820
3,705
5,928
4,542
Rated Internal Working Pressure for Copper Tube: ACR (Air Conditioning and Refrigeration Filed Service)
Tube Size (OD)
S=6000 psi 100 F
S=5100 psi 150 F
S=4900 psi 200F
S=4800 psi 250F
S=4700 psi 300 F
S=4000 psi 350F
S=3000 psi 400F
0.1250
3074
2613
2510
2459
2408
2049
1537
0.1875
1935
1645
1581
1548
1516
1290
968
0.2500
1406
1195
1148
1125
1102
938
703
0.3125
1197
1017
977
957
937
798
598
0.3750
984
836
803
787
770
656
492
0.5000
727
618
594
581
569
485
363
0.6250
618
525
504
494
484
412
309
0.7500
511
435
417
409
400
341
256
0.8750
582
495
475
466
456
388
291
1.1250
494
420
404
395
387
330
247
1.3750
439
373
358
351
344
293
219
1.6250
408
347
334
327
320
272
204
Pressure Rating for Seamless Stainless Coils ASTM A269 316/316L