Grade | Typical Application | Yield Strength (psi) |
H40 | Mild depth wells | 40,000 |
J55 | Shallow to medium wells | 55,000 |
K55 | Similar to J55 but higher strength | 55,000 |
N80 | Sour service, moderate strength | 80,000 |
L80 | Deep wells and sour gas applications | 80,000 |
C90 | High collapse resistance | 90,000 |
T95 | Sour service with corrosion resistance | 95,000 |
P110 | Ultra-deep and high-pressure wells | 110,000 |
Q125 | Ultra-high-pressure applications | 125,000 |
Thread Type | Description |
STC | Short round thread coupling |
LTC | Long round thread coupling |
BTC | Buttress thread coupling |
NU | Non-upset tubing connection |
EU | External upset tubing connection |
IJ | Integral joint tubing (no separate coupling) |
Used to assess toughness, this test measures how much energy the material absorbs when struck. Key areas tested include the pipe body, weld seam, and heat-affected zone, ensuring durability in harsh conditions.
OCTG includes casing, tubing, and drill pipe, with API 5CT specifically defining the manufacturing, mechanical properties, testing, and inspection standards for casing and tubing pipes. These components are vital to the integrity of a well, providing structural support and enabling safe fluid transportation under extreme downhole conditions.
Steel Grade | Application | PSL Available | H₂S Resistance | Tensile Strength (min) |
J55 | Standard shallow wells | PSL-1, PSL-2 | No | 517 MPa |
N80 | Medium-depth wells | PSL-1, PSL-2 | Limited | 689 MPa |
L80 | Sour service environments | PSL-1, PSL-2 | Yes | 655 MPa |
P110 | Deep, high-pressure wells | PSL-1, PSL-2 | No | 758 MPa |
DN | O. D. | Weight | W. T. | End Processing | |||||||||
Non-upset coupling-thread | Upset coupling-thread | Steel Grade | |||||||||||
in | mm | lb./ft. | lb./ft. | in | mm | H40 | J55 | L80 | N80 | C90 | T95 | P110 | |
2 3/8 | 2.38 | 60.3 | 4 | – | 0.167 | 4.24 | PU | PN | PN | PN | PN | PN | – |
4.6 | 4.7 | 0.19 | 4.83 | PNU | PNU | PNU | PNU | PNU | PNU | PNU | |||
5.8 | 5.95 | 0.254 | 6.45 | – | – | PNU | PNU | PNU | PNU | PNU | |||
6.6 | – | 0.295 | 7.49 | – | – | P | – | P | P | – | |||
7.35 | 7.45 | 0.336 | 8.53 | – | – | PU | – | PU | PU | – | |||
2 7/8 | 2.88 | 73 | 6.4 | 6.5 | 0.217 | 5.51 | PNU | PNU | – | – | – | – | – |
7.8 | 7.9 | 0.276 | 7.01 | – | – | – | – | – | – | – | |||
8.6 | 8.7 | 0.308 | 7.82 | – | – | PLB | PLB | PLBE | – | PLB | |||
9.35 | 9.45 | 0.34 | 8.64 | – | – | PLB | PLB | PLBE | – | PLB | |||
10.5 | – | 0.392 | 9.96 | – | – | PLB | PLB | PLB | – | PLB | |||
11.5 | – | 0.44 | 11.18 | – | – | – | – | PLB | – | ||||
3 1/2 | 3.5 | 88.9 | 7.7 | – | 0.216 | 5.49 | PN | PN | PN | PN | PN | PN | – |
9.2 | 9.3 | 0.254 | 6.45 | PNU | PNU | PNU | PNU | PNU | PNU | PNU | |||
10.2 | – | 0.289 | 7.34 | PN | PN | PN | PN | PN | PN | – | |||
12.7 | 12.95 | 0.375 | 9.52 | – | – | PNU | PNU | PNU | PNU | PNU | |||
14.3 | – | 0.43 | 10.92 | – | – | P | – | P | P | – | |||
15.5 | – | 0.476 | 12.09 | – | – | P | – | P | P | – | |||
17 | – | 0.53 | 13.46 | – | – | P | – | P | P | – | |||
4 | 4 | 102 | 9.5 | – | 0.226 | 5.74 | PN | PN | PN | PN | PN | PN | – |
– | 11 | 0.262 | 6.65 | PU | PU | PU | PU | PU | PU | – | |||
13.2 | – | 0.33 | 8.38 | – | – | P | – | P | P | – | |||
16.1 | – | 0.415 | 10.54 | – | – | P | – | P | P | – | |||
18.9 | – | 0.5 | 12.7 | – | – | P | – | P | P | – | |||
22.2 | – | 0.61 | 15.49 | – | – | P | – | P | P | – | |||
4 1/2 | 4.5 | 114 | 12.6 | 12.75 | 0.271 | 6.88 | PNU | PNU | PNU | PNU | PNU | PNU | – |
15.2 | – | 0.337 | 8.56 | – | – | P | – | P | P | – | |||
17 | – | 0.38 | 9.65 | – | – | P | – | P | P | – | |||
18.9 | – | 0.43 | 10.92 | – | – | P | – | P | P | PLB | |||
21.5 | – | 0.5 | 12.7 | – | – | P | – | P | P | PLB | |||
23.7 | – | 0.56 | 14.22 | – | – | P | – | P | P | PLB | |||
26.1 | – | 0.63 | 16 | – | – | P | – | P | P | PLB | |||
P——Plain;N—— Non-upset coupling-thread;U—— Upset coupling-thread; L——Integral |
DN | O. D. | Weight | W. T. | End Machining Form | ||||||||
Steel Grade | ||||||||||||
in | mm | lb/ft | kg/m | in | mm | H40 | J55 | L80 | N80 | C90 | P110 | |
K55 | T95 | |||||||||||
4 1/2 | 4.500 | 114.3 | 9.5 | 14.14 | 0.205 | 5.21 | PS | PS | – | – | – | – |
10.5 | 15.63 | 0.224 | 5.69 | – | PSB | – | – | – | – | |||
11.6 | 17.26 | 0.250 | 6.35 | – | PSLB | PLB | PLB | PLB | PLB | |||
13.5 | 20.09 | 0.290 | 7.37 | – | – | PLB | PLB | PLB | PLB | |||
15.1 | 22.47 | 0.337 | 9.56 | – | – | – | – | – | PLB | |||
5 | 5.000 | 127 | 11.5 | 17.11 | 0.220 | 5.59 | – | PS | – | – | – | – |
13 | 19.35 | 0.253 | 6.43 | – | PSLB | – | – | – | – | |||
15 | 22.32 | 0.296 | 7.52 | – | PSLB | PLB | PLB | PLBE | PLB | |||
18 | 26.79 | 0.362 | 9.19 | – | – | PLB | PLB | PLBE | PLB | |||
21.4 | 31.85 | 0.437 | 11.1 | – | – | PLB | PLB | PLB | PLB | |||
23.2 | 34.53 | 0.478 | 12.14 | – | – | – | – | PLB | – | |||
24.1 | 35.86 | 0.500 | 12.7 | – | – | – | – | PLB | – | |||
5 1/2 | 5.500 | 139.7 | 14 | 20.83 | 0.244 | 6.2 | PS | PS | – | – | – | – |
15.5 | 23.07 | 0.275 | 6.98 | – | PSLB | – | – | – | – | |||
17 | 25.3 | 0.304 | 7.72 | – | PSLB | PLB | PLB | PLBE | PLB | |||
20 | 29.76 | 0.361 | 9.17 | – | – | PLB | PLB | PLBE | PLB | |||
23 | 34.23 | 0.415 | 10.54 | – | – | PLB | PLB | PLBE | PLB | |||
26.8 | 39.88 | 0.500 | 12.7 | – | – | – | – | – | – | |||
29.7 | 44.2 | 0.562 | 14.27 | – | – | – | – | – | – | |||
32.6 | 48.51 | 0.625 | 15.88 | – | – | – | – | – | – | |||
35.3 | 52.53 | 0.687 | 17.45 | – | – | – | – | – | – | |||
38 | 56.55 | 0.750 | 19.05 | – | – | – | – | – | – | |||
40.5 | 60.27 | 0.812 | 20.62 | – | – | – | – | – | – | |||
43.1 | 64.14 | 0.875 | 22.22 | – | – | – | – | – | – | |||
6 5/8 | 6.625 | 168.28 | 20 | 29.76 | 0.288 | 7.32 | PS | PSLB | – | – | – | – |
24 | 35.72 | 0.352 | 8.94 | – | PSLB | PLB | PLB | PLBE | PLB | |||
28 | 41.67 | 0.417 | 10.59 | – | – | PLB | PLB | PLBE | PLB | |||
32 | 47.62 | 0.475 | 12.06 | – | – | PLB | PLB | PLBE | PLB | |||
7 | 7.000 | 177.8 | 17 | 25.3 | 0.231 | 5.87 | PS | – | – | – | – | – |
20 | 29.76 | 0.272 | 6.91 | PS | PS | – | – | – | – | |||
23 | 34.23 | 0.317 | 8.05 | – | PSLB | PLB | PLB | PLBE | – | |||
26 | 38.69 | 0.362 | 9.19 | – | PSLB | PLB | PLB | PLBE | PLB | |||
29 | 43.16 | 0.408 | 10.36 | – | – | PLB | PLB | PLBE | PLB | |||
32 | 47.62 | 0.453 | 11.51 | – | – | PLB | PLB | PLBE | PLB | |||
35 | 52.09 | 0.498 | 12.65 | – | – | PLB | PLB | PLBE | PLB | |||
38 | 56.55 | 0.540 | 13.72 | – | – | PLB | PLB | PLBE | PLB | |||
42.7 | 63.54 | 0.625 | 15.88 | – | – | – | – | – | – | |||
46.4 | 69.05 | 0.687 | 17.45 | – | – | – | – | – | – | |||
50.1 | 74.56 | 0.750 | 19.05 | – | – | – | – | – | – | |||
53.6 | 79.77 | 0.812 | 20.62 | – | – | – | – | – | – | |||
57.1 | 84.97 | 0.875 | 22.22 | – | – | – | – | – | – | |||
7 5/8 | 7.625 | 193.68 | 24 | 35.72 | 0.300 | 7.62 | PS | – | – | – | – | – |
26.4 | 39.29 | 0.328 | 8.33 | – | PSLB | PLB | PLB | PLBE | PLB | |||
29.7 | 44.2 | 0.375 | 9.52 | – | – | PLB | PLB | PLBE | PLB | |||
33.7 | 50.15 | 0.430 | 10.92 | – | – | PLB | PLB | PLBE | PLB | |||
39 | 58.05 | 0.500 | 12.7 | – | – | PLB | PLB | PLBE | PLB | |||
42.8 | 63.69 | 0.562 | 14.27 | – | – | PLB | PLB | PLB | PLB | |||
45.3 | 67.41 | 0.595 | 15.11 | – | – | PLB | PLB | PLB | PLB | |||
47.1 | 70.09 | 0.625 | 15.88 | – | – | PLB | PLB | PLB | PLB | |||
51.2 | 76.19 | 0.687 | 17.45 | – | – | – | – | – | – | |||
55.3 | 80.3 | 0.750 | 19.05 | – | – | – | – | – | – | |||
8 5/8 | 8.625 | 219.08 | 24 | 35.72 | 0.264 | 6.71 | – | PS | – | – | – | – |
28 | 41.62 | 0.304 | 7.72 | PS | – | – | – | – | – | |||
32 | 47.62 | 0.352 | 8.94 | PS | PSLB | – | – | – | – | |||
36 | 53.57 | 0.400 | 10.16 | – | PSLB | PLB | PLB | PLBE | PLB | |||
40 | 59.53 | 0.450 | 11.43 | – | – | PLB | PLB | PLBE | PLB | |||
44 | 65.48 | 0.500 | 12.7 | – | – | PLB | PLB | PLBE | PLB | |||
49 | 72.92 | 0.557 | 14.15 | – | – | PLB | PLB | PLBE | PLB | |||
9 5/8 | 9.625 | 244.48 | 32.3 | 48.07 | 0.312 | 7.92 | PS | – | – | – | – | – |
36 | 53.57 | 0.352 | 8.94 | PS | PSLB | – | – | – | – | |||
40 | 59.53 | 0.395 | 10.03 | – | PSLB | PLB | PLB | PLBE | – | |||
43.5 | 64.73 | 0.435 | 11.05 | – | – | PLB | PLB | PLBE | PLB | |||
47 | 69.94 | 0.472 | 11.99 | – | – | PLB | PLB | PLBE | PLB | |||
53.5 | 79.62 | 0.545 | 13.84 | – | – | PLB | PLB | PLBE | PLB | |||
58.4 | 86.91 | 0.595 | 15.11 | – | – | PLB | PLB | PLB | PLB | |||
59.4 | 88.4 | 0.609 | 15.47 | – | – | – | – | – | – | |||
64.9 | 96.58 | 0.672 | 17.07 | – | – | – | – | – | – | |||
70.3 | 104.62 | 0.734 | 18.64 | – | – | – | – | – | – | |||
75.6 | 112.5 | 0.797 | 20.24 | – | – | – | – | – | – | |||
10 3/4 | 10.750 | 273.05 | 32.75 | 48.74 | 0.279 | 7.09 | PS | – | – | – | – | – |
40.5 | 60.27 | 0.350 | 8.89 | PS | PSB | – | – | – | – | |||
15.5 | 67.71 | 0.400 | 10.16 | – | PSB | – | – | – | – | |||
51 | 75.9 | 0.450 | 11.43 | – | PSB | PSB | PSB | PSBE | PSB | |||
55.5 | 82.59 | 0.495 | 12.57 | – | – | PSB | PSB | PSBE | PSB | |||
60.7 | 90.33 | 0.545 | 13.84 | – | – | – | – | PSBE | PSB | |||
65.7 | 97.77 | 0.595 | 15.11 | – | – | – | – | PSB | PSB | |||
73.2 | 108.93 | 0.672 | 17.07 | – | – | – | – | – | – | |||
79.2 | 117.86 | 0.734 | 18.64 | – | – | – | – | – | – | |||
85.3 | 126.94 | 0.797 | 20.24 | – | – | – | – | – | – | |||
11 3/4 | 11.750 | 42 | 62.5 | 0.333 | 8.46 | PS | – | – | – | – | – | |
47 | 69.94 | 0.375 | 20.24 | – | – | – | – | – | – | |||
54 | 80.36 | 0.435 | 8.46 | – | – | – | – | – | – | |||
60 | 89.29 | 0.489 | 9.53 | – | – | – | – | – | – | |||
65 | 96.73 | 0.534 | 11.05 | – | – | – | – | – | – | |||
71 | 105.66 | 0.582 | 14.42 | – | – | – | – | – | – | |||
13 3/8 | 13.375 | 339.73 | 48 | 71.43 | 0.330 | 8.38 | PS | – | – | – | – | – |
54.5 | 81.1 | 0.380 | 9.65 | – | PSB | – | – | – | – | |||
61 | 90.78 | 0.430 | 10.92 | – | PSB | – | – | – | – | |||
68 | 101.19 | 0.480 | 12.19 | – | PSB | PSB | PSB | PSB | PSB | |||
72 | 107.15 | 0.514 | 13.06 | – | – | PSB | PSB | PSB | PSB | |||
16 | 16.000 | 406.4 | 65 | 96.73 | 0.375 | 9.53 | PS | – | – | – | – | – |
75 | 111.61 | 0.438 | 11.13 | – | PSB | – | – | – | – | |||
84 | 125.01 | 0.495 | 12.57 | – | PSB | – | – | – | – | |||
109 | 162.21 | 0.656 | 16.66 | – | P | P | P | – | P | |||
18 5/8 | 18.625 | 473.08 | 87.5 | 130.21 | 0.435 | 11.05 | PS | PSB | – | – | – | – |
20 | 20.000 | 508 | 94 | 139.89 | 0.438 | 11.13 | PSL | PSLB | – | – | – | – |
106.5 | 158.49 | 0.500 | 12.7 | – | PSLB | – | – | – | – | |||
133 | 197.93 | 0.635 | 16.13 | – | PSLB | – | – | – | – | |||
P——Plain;S——Short-thread;L——Long-thread;B——Buttress thread;E——Extreme thread |