OCTG casing pipe meaning
OCTG casing pipe, which stands for "Oil Country Tubular Goods," is a category of seamless steel products, including drill pipes, casing and tubing, that are essential for drilling and producing oil and gas. Casing pipes specifically are used to line the borehole, preventing the wellbore from collapsing and isolating different subsurface layers. These pipes are constructed from high-strength steel grades to endure the extreme pressures, temperatures, and corrosive conditions typically found in oil and gas wells. They are vital components in maintaining the integrity of wells during exploration and production activities.
API SPEC 5CT establishes the standard sizing system for tubing and casing used in oil and gas wells, covering a defined range of steel pipe dimensions. According to this specification, OCTG casing is commonly produced in diameters from 4 1/2" to 20", while tubing is available in smaller sizes, typically between 1.05" and 4 1/2".
Casing Pipe Size Chart
The size of casing pipes varies depending on their application in the oil, gas, and water drilling industries. Here's a general casing pipe size chart with common dimensions, based on API 5CT standards:
|
Lables
|
Outside
|
Nominal
|
Wall
|
Inside
|
Drift
|
Calculated mass C
|
|
diameter
|
diameter
|
thickness
|
diameter
|
diameter
|
Plain End
|
Mass gain or loss due to end finishing (lb)
|
|
|
|
|
|
|
Round thread
|
Buttress thread
|
|
1
|
2
|
D (in)
|
lb/ft
|
t (in)
|
d (in)
|
in
|
lb/ft
|
Short
|
Long
|
RC
|
SCC
|
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
12
|
|
4 1/2
|
9.5
|
4.5
|
9.5
|
0.205
|
4.09
|
3.965
|
9.41
|
4.2
|
|
|
|
|
4 1/2
|
10.5
|
4.5
|
10.5
|
0.224
|
4.052
|
3.927
|
10.24
|
3.8
|
|
5
|
2.56
|
|
4 1/2
|
11.6
|
4.5
|
11.6
|
0.25
|
4
|
3.875
|
11.36
|
3.4
|
3.8
|
4.6
|
2.16
|
|
4 1/2
|
13.5
|
4.5
|
13.5
|
0.29
|
3.92
|
3.795
|
13.05
|
|
3.2
|
4
|
1.56
|
|
4 1/2
|
15.1
|
4.5
|
15.1
|
0.337
|
3.826
|
3.701
|
15
|
|
2.8
|
3.2
|
0.76
|
|
5
|
11.5
|
5
|
11.5
|
0.22
|
4.56
|
4.435
|
11.24
|
5.4
|
|
|
|
|
5
|
13
|
5
|
13
|
0.253
|
4.494
|
4.369
|
12.84
|
4.8
|
5.8
|
6.6
|
2.42
|
|
5
|
15
|
5
|
15
|
0.296
|
4.408
|
4.283
|
14.88
|
4.2
|
5.2
|
5.8
|
1.62
|
|
5
|
18
|
5
|
18
|
0.362
|
4.276
|
4.151
|
17.95
|
|
4.2
|
4.4
|
0.22
|
|
5
|
21.4
|
5
|
21.4
|
0.437
|
4.126
|
4.001
|
21.32
|
|
2.95
|
2.46
|
-1.72
|
|
5
|
23.2
|
5
|
23.2
|
0.478
|
4.044
|
3.919
|
23.11
|
|
2.3
|
2.05
|
-2.09
|
|
5
|
24.1
|
5
|
24.1
|
0.5
|
4
|
3.875
|
24.05
|
|
1.95
|
1.24
|
-2.94
|
|
5 1/2
|
14
|
5.5
|
14
|
0.244
|
5.015
|
4.887
|
13.71
|
5.4
|
|
|
|
|
5 1/2
|
15.5
|
5.5
|
15.5
|
0.275
|
4.95
|
4.825
|
15.36
|
4.8
|
5.8
|
6.4
|
2.1
|
|
5 1/2
|
17
|
5.5
|
17
|
0.304
|
4.892
|
4.767
|
16.89
|
4.4
|
5.4
|
5.8
|
1.5
|
|
5 1/2
|
20
|
5.5
|
20
|
0.361
|
4.778
|
4.653
|
19.83
|
|
4.4
|
4.6
|
0.3
|
|
5 1/2
|
23
|
5.5
|
23
|
0.415
|
4.67
|
4.545
|
22.56
|
|
3.2
|
3.4
|
0.9
|
|
5 1/2
|
26.8
|
5.5
|
26.8
|
0.5
|
4.5
|
4.375
|
26.72
|
|
|
|
|
|
5 1/2
|
29.7
|
5.5
|
29.7
|
0.562
|
4.376
|
4.251
|
29.67
|
|
|
|
|
|
5 1/2
|
32.6
|
5.5
|
32.6
|
0.625
|
4.25
|
4.125
|
32.57
|
|
|
|
|
|
5 1/2
|
35.3
|
5.5
|
35.3
|
0.687
|
4.126
|
4.001
|
35.35
|
|
|
|
|
|
5 1/2
|
38
|
5.5
|
38
|
0.75
|
4
|
3.875
|
38.08
|
|
|
|
|
|
5 1/2
|
40.5
|
5.5
|
40.5
|
0.812
|
3.876
|
3.751
|
40.69
|
|
|
|
|
|
5 1/2
|
43.1
|
5.5
|
43.1
|
0.875
|
3.75
|
3.625
|
43.26
|
|
|
|
|
|
6 5/8
|
20
|
6.625
|
20
|
0.288
|
6.049
|
5.924
|
19.51
|
11
|
13.6
|
14.4
|
2.38
|
|
6 5/8
|
24
|
6.625
|
24
|
0.352
|
5.921
|
5.796
|
23.6
|
9.6
|
12
|
12.6
|
0.58
|
|
6 5/8
|
28
|
6.625
|
28
|
0.417
|
5.791
|
5.666
|
27.67
|
|
10.2
|
10.6
|
-1.42
|
|
6 5/8
|
32
|
6.625
|
32
|
0.475
|
5.675
|
5.55
|
31.23
|
|
8.8
|
9
|
-3.02
|
|
7
|
17
|
7
|
17
|
0.231
|
6.538
|
6.413
|
16.72
|
10
|
|
|
|
|
7
|
20
|
7
|
20
|
0.272
|
6.456
|
6.331
|
19.56
|
9.4
|
|
|
|
|
7
|
23
|
7
|
23
|
0.317
|
6.366
|
6.25
|
22.65
|
8
|
10.4
|
11
|
1.6
|
|
7
|
23
|
7
|
23
|
0.317
|
6.366
|
6.241
|
22.65
|
8
|
10.4
|
11
|
1.6
|
|
7
|
26
|
7
|
26
|
0.362
|
6.276
|
6.151
|
25.69
|
7.2
|
9.4
|
9.6
|
0.2
|
|
7
|
29
|
7
|
29
|
0.408
|
6.184
|
6.059
|
28.75
|
|
8
|
8.2
|
1.2
|
|
7
|
32
|
7
|
32
|
0.453
|
6.094
|
6
|
31.7
|
|
6.6
|
6.8
|
2.6
|
|
7
|
32
|
7
|
32
|
0.453
|
6.094
|
5.969
|
31.7
|
|
6.6
|
6.8
|
2.6
|
|
7
|
35
|
7
|
35
|
0.498
|
6.004
|
5.879
|
34.61
|
|
5.6
|
5.6
|
3.8
|
|
7
|
38
|
7
|
38
|
0.54
|
5.92
|
5.795
|
37.29
|
|
4.4
|
4.2
|
5.2
|
|
7
|
42.7
|
7
|
42.7
|
0.625
|
5.75
|
5.625
|
42.59
|
|
|
|
|
|
7
|
46.4
|
7
|
46.4
|
0.687
|
5.625
|
5.5
|
46.36
|
|
|
|
|
|
7
|
50.1
|
7
|
50.1
|
0.75
|
5.5
|
5.375
|
50.11
|
|
|
|
|
|
7
|
53.6
|
7
|
53.6
|
0.812
|
5.376
|
5.251
|
53.71
|
|
|
|
|
|
7
|
57.1
|
7
|
57.1
|
0.875
|
5.25
|
5.125
|
57.29
|
|
|
|
|
|
7 5/8
|
24
|
7.625
|
24
|
0.3
|
7.025
|
6.9
|
23.49
|
15.8
|
|
|
|
|
7 5/8
|
26.4
|
7.625
|
26.4
|
0.328
|
6.969
|
6.844
|
25.59
|
15.2
|
19
|
20.6
|
6.21
|
|
7 5/8
|
29.7
|
7.625
|
29.7
|
0.375
|
6.875
|
6.75
|
29.06
|
|
17.4
|
18.8
|
4.41
|
|
7 5/8
|
33.7
|
7.625
|
33.7
|
0.43
|
6.765
|
6.64
|
33.07
|
|
15.8
|
17
|
2.61
|
|
7 5/8
|
39
|
7.625
|
39
|
0.5
|
6.625
|
6.5
|
38.08
|
|
13.6
|
14.6
|
0.21
|
|
7 5/8
|
42.8
|
7.625
|
42.8
|
0.562
|
6.501
|
6.376
|
42.43
|
|
12.01
|
11.39
|
-3.01
|
|
7 5/8
|
45.3
|
7.625
|
45.3
|
0.595
|
6.435
|
6.31
|
44.71
|
|
11.04
|
11.04
|
-3.36
|
|
7 5/8
|
47.1
|
7.625
|
47.1
|
0.625
|
6.375
|
6.25
|
46.77
|
|
10.16
|
9.23
|
-5.17
|
|
7 5/8
|
51.2
|
7.625
|
51.2
|
0.687
|
6.251
|
6.126
|
50.95
|
|
|
|
|
|
7 5/8
|
55.3
|
7.625
|
55.3
|
0.75
|
6.125
|
6
|
55.12
|
|
|
|
|
|
7 3/4
|
46.1
|
7.75
|
46.1
|
0.595
|
6.56
|
6.5
|
45.51
|
|
|
|
|
|
7 3/4
|
46.1
|
7.75
|
46.1
|
0.595
|
6.56
|
6.435
|
45.51
|
|
|
|
|
|
8 5/8
|
24
|
8.625
|
24
|
0.264
|
8.097
|
7.972
|
23.6
|
23.6
|
|
|
|
|
8 5/8
|
28
|
8.625
|
28
|
0.304
|
8.017
|
7.892
|
27.04
|
22.2
|
|
|
|
|
8 5/8
|
32
|
8.625
|
32
|
0.352
|
7.921
|
7.875
|
31.13
|
20.8
|
27.6
|
28.3
|
6.03
|
|
8 5/8
|
32
|
8.625
|
32
|
0.352
|
7.921
|
7.796
|
31.13
|
20.8
|
27.6
|
28.2
|
6.03
|
|
8 5/8
|
36
|
8.625
|
36
|
0.4
|
7.825
|
7.7
|
35.17
|
19.4
|
25.6
|
26.2
|
4.03
|
|
8 5/8
|
40
|
8.625
|
40
|
0.45
|
7.725
|
7.625
|
39.33
|
|
23.8
|
24.2
|
2.03
|
|
8 5/8
|
40
|
8.625
|
40
|
0.45
|
7.725
|
7.6
|
39.33
|
|
23.8
|
24.2
|
2.03
|
|
8 5/8
|
44
|
8.625
|
44
|
0.5
|
7.625
|
7.5
|
43.43
|
|
21.8
|
22.2
|
0.03
|
|
8 5/8
|
49
|
8.625
|
49
|
0.557
|
7.511
|
7.286
|
48.04
|
|
19.6
|
19.8
|
-2.37
|
|
9 5/8
|
32.3
|
9.625
|
32.3
|
0.312
|
9.001
|
8.845
|
31.06
|
24.4
|
|
|
|
|
9 5/8
|
36
|
9.625
|
36
|
0.352
|
8.921
|
8.876
|
34.89
|
23
|
32
|
31
|
6.48
|
|
9 5/8
|
40
|
9.625
|
40
|
0.395
|
8.835
|
8.75
|
38.97
|
21.4
|
30
|
29
|
4.48
|
|
9 5/8
|
40
|
9.625
|
40
|
0.395
|
8.835
|
8.679
|
38.97
|
21.4
|
30
|
29
|
4.48
|
|
9 5/8
|
43.5
|
9.625
|
43.5
|
0.435
|
8.755
|
8.599
|
42.73
|
|
28.2
|
27.2
|
2.68
|
|
9 5/8
|
47
|
9.625
|
47
|
0.472
|
8.681
|
8.525
|
46.18
|
|
26.6
|
25.6
|
1.08
|
|
9 5/8
|
53.5
|
9.625
|
53.5
|
0.545
|
8.535
|
8.5
|
52.9
|
|
23.4
|
22.4
|
-2.12
|
|
9 5/8
|
53.5
|
9.625
|
53.5
|
0.545
|
8.535
|
8.379
|
52.9
|
|
23.4
|
22.4
|
-2.12
|
|
9 5/8
|
58.4
|
9.625
|
58.4
|
0.595
|
8.435
|
8.375
|
57.44
|
|
21.5
|
20.13
|
-4.4
|
|
9 5/8
|
58.4
|
9.625
|
58.4
|
0.595
|
8.435
|
8.279
|
57.44
|
|
21.5
|
20.13
|
-4.4
|
|
9 5/8
|
59.4
|
9.625
|
59.4
|
0.609
|
8.407
|
8.251
|
58.7
|
|
|
|
|
|
9 5/8
|
64.9
|
9.625
|
64.9
|
0.672
|
8.281
|
8.125
|
64.32
|
|
|
|
|
|
9 5/8
|
70.3
|
9.625
|
70.3
|
0.734
|
8.157
|
8.001
|
69.76
|
|
|
|
|
|
9 5/8
|
75.6
|
9.625
|
75.6
|
0.797
|
8.031
|
7.875
|
75.21
|
|
|
|
|
|
10 3/4
|
32.75
|
10.75
|
32.75
|
0.279
|
10.192
|
10.036
|
31.23
|
29
|
|
|
|
|
10 3/4
|
40.5
|
10.75
|
40.5
|
0.35
|
10.05
|
9.894
|
38.91
|
26.4
|
|
34.4
|
7.21
|
|
10 3/4
|
45.5
|
10.75
|
45.5
|
0.4
|
9.95
|
9.875
|
44.26
|
24.4
|
|
31.8
|
4.61
|
|
10 3/4
|
45.5
|
10.75
|
45.5
|
0.4
|
9.95
|
9.794
|
44.26
|
24.4
|
|
31.8
|
4.61
|
|
10 3/4
|
51
|
10.75
|
51
|
0.45
|
9.85
|
9.694
|
49.55
|
22.6
|
|
29.4
|
2.21
|
|
10 3/4
|
55.5
|
10.75
|
55.5
|
0.495
|
9.76
|
9.625
|
54.26
|
20.8
|
|
27
|
-0.19
|
|
10 3/4
|
55.5
|
10.75
|
55.5
|
0.495
|
9.76
|
9.604
|
54.26
|
20.8
|
|
27
|
-0.19
|
|
10 3/4
|
60.7
|
10.75
|
60.7
|
0.545
|
9.66
|
9.504
|
59.45
|
18.8
|
|
24.4
|
|
|
10 3/4
|
65.7
|
10.75
|
65.7
|
0.595
|
9.56
|
9.404
|
64.59
|
16.8
|
|
22
|
|
|
10 3/4
|
73.2
|
10.75
|
73.2
|
0.672
|
9.406
|
9.25
|
72.4
|
|
|
|
|
|
10 3/4
|
79.2
|
10.75
|
79.2
|
0.734
|
9.282
|
9.126
|
78.59
|
|
|
|
|
|
10 3/4
|
85.3
|
10.75
|
85.3
|
0.797
|
9.156
|
9
|
84.8
|
|
|
|
|
|
11 3/4
|
42
|
11.75
|
42
|
0.333
|
11.084
|
11
|
40.64
|
29.6
|
|
|
|
|
11 3/4
|
42
|
11.75
|
42
|
0.333
|
11.084
|
10.928
|
40.64
|
29.6
|
|
|
|
|
11 3/4
|
47
|
11.75
|
47
|
0.375
|
11
|
10.844
|
45.6
|
27.6
|
|
35.8
|
|
|
11 3/4
|
54
|
11.75
|
54
|
0.435
|
10.88
|
10.724
|
52.62
|
25
|
|
32.4
|
|
|
11 3/4
|
60
|
11.75
|
60
|
0.489
|
10.772
|
10.625
|
58.87
|
22.6
|
|
29.6
|
|
|
11 3/4
|
60
|
11.75
|
60
|
0.489
|
10.772
|
10.616
|
58.87
|
22.6
|
|
29.6
|
|
|
11 3/4
|
65
|
11.75
|
65
|
0.534
|
10.682
|
10.625
|
64.03
|
|
|
|
|
|
11 3/4
|
65
|
11.75
|
65
|
0.534
|
10.682
|
10.625
|
64.03
|
|
|
|
|
|
11 3/4
|
71
|
11.75
|
71
|
0.582
|
10.586
|
10.43
|
69.48
|
|
|
|
|
|
13 3/8
|
48
|
13.375
|
48
|
0.33
|
12.715
|
12.559
|
46.02
|
33.2
|
|
|
|
|
13 3/8
|
54.5
|
13.375
|
54.5
|
0.38
|
12.615
|
12.459
|
52.79
|
30.8
|
|
40.2
|
|
|
13 3/8
|
61
|
13.375
|
61
|
0.43
|
12.515
|
12.359
|
59.5
|
28.4
|
|
36.8
|
|
|
13 3/8
|
68
|
13.375
|
68
|
0.48
|
12.415
|
12.259
|
66.17
|
25.8
|
|
33.6
|
|
|
13 3/8
|
72
|
13.375
|
72
|
0.514
|
12.347
|
12.25
|
70.67
|
24.2
|
|
31.6
|
|
|
13 3/8
|
72
|
13.375
|
72
|
0.514
|
12.347
|
12.191
|
70.67
|
24.2
|
|
31.6
|
|
|
16
|
65
|
16
|
65
|
0.375
|
15.25
|
15.062
|
62.64
|
42.6
|
|
|
|
|
16
|
75
|
16
|
75
|
0.438
|
15.124
|
14.936
|
72.86
|
38.2
|
|
45.6
|
|
|
16
|
84
|
16
|
84
|
0.495
|
15.01
|
14.822
|
82.05
|
34.2
|
|
39.6
|
|
|
16
|
109
|
16
|
109
|
0.656
|
14.688
|
14.5
|
107.6
|
|
|
|
|
|
18 5/8
|
87.5
|
18.625
|
87.5
|
0.435
|
17.755
|
17.567
|
84.59
|
73.6
|
|
86.4
|
|
|
20
|
94
|
20
|
94
|
0.438
|
19.124
|
18.936
|
91.59
|
47
|
61.2
|
54.8
|
|
|
20
|
106.5
|
20
|
106.5
|
0.5
|
19
|
18.812
|
104.23
|
41.6
|
54.8
|
48.4
|
|
|
20
|
133
|
20
|
133
|
0.635
|
18.73
|
18.542
|
131.45
|
30
|
40.6
|
35.2
|
|
Key Notes on Casing Sizes:
-
OD (Outer Diameter): The external diameter of the casing pipe. It determines the size of the hole required for installation.
-
Weight (lbs/ft): Describes the linear weight of the casing, which varies based on wall thickness and steel grade.
-
Wall Thickness: Affects the casing's ability to withstand pressure and collapse forces.
-
ID (Inner Diameter): Impacts the flow capacity of the well.
If you are considering casing pipes for a specific application, ensure you check compatibility with your drilling equipment and project requirements.
Steel Pipe Dimension 3 elements
A complete description for steel pipe dimension includes outer diameter (OD), wall thickness (WT), pipe length (Normally 20 ft 6 meter, or 40 ft 12 meters).Through these elements we could calculate the pipe weight, how much pressure the pipe could bear, and the cost per foot or per meter.
So that’s why we always need to know the correct pipe size.BAOWI Steel We provide all kinds of oil pipes and casings. If you need, please contact us.
Steel Casing Pipe FAQ (Quick Guide)
1. How to choose the casing size?
The casing Inside Diameter (ID) should be 2-4 inches larger than the Outside Diameter (OD) of the carrier pipe (including joints) to allow for spacers and easy installation.
2. What is the standard wall thickness?
For most road crossings (12"-24" diameter), the industry standard is 0.250" (1/4") or 0.375" (3/8"). Larger or deeper bores may require 0.500" or more.
3. ASTM A252 vs. A139: Which is better?
ASTM A252: Best for structural piling and load-bearing.ASTM A139 Grade B: The preferred choice for Jack and Bore due to superior weld strength and straighter alignment.
4. Does casing pipe need coating?
In corrosive or acidic soils, coatings like Bitumen or Coal Tar Epoxy are used. For standard utility sleeves, bare steel with an added "corrosion allowance" (extra wall thickness) is common.
5. Why use casing spacers?
Spacers center the carrier pipe, provide electrical insulation to prevent galvanic corrosion, and protect the carrier pipe’s coating during installation.
English
Español
بالعربية
Phone : 
Whatsapp : 
Email : 
