The manufacturing process is primarily where seamless pipe and erw pipe differ. Electric resistance welding is used to create erw pipes, whereas seamless pipes are typically formed from a single billet of raw material. Thecost difference between seamless and erw pipes depending on the production techniques. While the seamless pipes require precise drawing, the erw approach involves welding. Procedures can become more expensive than one another depending on the size, precision, and material used to manufacture the pipes.
The surface smoothness of seamless pipes is high and their absolute roughness is lower. In order to create pipes without joints, seamless pipes are drawn. For drawn seamless pipes, the material's strength is equal to the pipe's strength. To create the pipes, the erw pipes are welded from a sheet, plate, or coil. The pipe's weakest component, the welded connection, influences the pipe's overall strength. The welded joint only allows for the strength of the welded point, even when the material has a higher strength value. One of the explanations for the usage of seamless pipes in precise applications requiring great strength is due to this.
A leak or breach in the middle of an operation cannot be tolerated by the oil and gas industries. The result would be terrible and more expensive. The pipes must be highly precise and have uniform strength throughout for better couplings. The edges of the pipes and the wall thickness are not as smooth in the erw pipes as they are in the seamless pipes, indicating that the erw pipes actually have a higher absolute roughness. This is important when using fittings to join the edges. The oil and gas applications are vulnerable when pipes and pipe fittings don't fit together precisely. This is the primary justification for the use of seamless pipes in industrial applications for oil and gas.
The seamless and erw pipes both involve heating up the material. The seamless pipes can be produced through cold drawing or hot drawing as well. The cold drawing procedure happens at room temperature where deformations due to the softness of the heated metal are very less likely. The erw process on the other hand involves heating up the coil, strip, plate or sheet to desired temperatures for welding into a pipe. This can result in deformed thicknesses and edges along the pipe.
The seamless pipes will not have tracks or joints of welding even on the inside of the pipes. There can be a difference seen in the welded pipes that identify the welded joint. There are also markings that verify if the pipe is seamless or erw.
Different application types use the different types of pipes. Both the pipes come in various sizes but the erw pipes can be produced in larger diameters than the drawn seamless pipes.
| ID | NOMINAL PIPE SIZE (DN) |
OUT DIAMTER IN (MM) |
WEIGHT LB/FT (KG/M) |
WT IN (MM) |
|---|---|---|---|---|
| 5S | 1/8 (6) |
0.405 (10.3) |
... | *1 |
| 10S | 1/8 (6) |
0.405 (10.3) |
0.19 (0.28) |
0.049 (1.24) *1 |
| 40S | 1/8 (6) |
0.405 (10.3) |
0.24 (0.37) |
0.068 (1.73) |
| 80S | 1/8 (6) |
0.405 (10.3) |
0.31 (0.47) |
0.095 (2.41) |
| 5S | 1/4 (8) |
0.54 (13.7) |
... | *1 |
| 10S | 1/4 (8) |
0.54 (13.7) |
0.33 (0.49) |
0.065 (1.65) *1 |
| 40S | 1/4 (8) |
0.54 (13.7) |
0.43 (0.63) |
0.088 (2.24) |
| 80S | 1/4 (8) |
0.54 (13.7) |
0.54 (0.8) |
0.119 (3.02) |
| 5S | 3/8 (10) |
0.675 (17.1) |
... | *1 |
| 10S | 3/8 (10) |
0.675 (17.1) |
0.42 (0.63) |
0.065 (1.65) *1 |
| 40S | 3/8 (10) |
0.675 (17.1) |
0.57 (0.84) |
0.091 (2.31) |
| 80S | 3/8 (10) |
0.675 (17.1) |
0.74 (1.1) |
0.126 (3.2) |
| 5S | 1/2 (15) |
0.84 (21.3) |
0.54 (0.8) |
0.065 (1.65) *1 |
| 10S | 1/2 (15) |
0.84 (21.3) |
0.67 (1.0) |
0.083 (2.11) *1 |
| 40S | 1/2 (15) |
0.84 (21.3) |
0.85 (1.27) |
0.109 (2.77) |
| 80S | 1/2 (15) |
0.84 (21.3) |
1.09 (1.62) |
0.147 (3.73) |
| 5S | 3/4 (20) |
1.05 (26.7) |
0.68 (1.02) |
0.065 (1.65) *1 |
| 10S | 3/4 (20) |
1.05 (26.7) |
0.86 (1.28) |
0.083 (2.11) *1 |
| 40S | 3/4 (20) |
1.05 (26.7) |
1.13 (1.69) |
0.113 (2.87) |
| 80S | 3/4 (20) |
1.05 (26.7) |
1.48 (2.2) |
0.154 (3.91) |
| 5S | 1 (25) |
1.315 (33.4) |
0.87 (1.29) |
0.065 (1.65) *1 |
| 10S | 1 (25) |
1.315 (33.4) |
1.41 (2.09) |
0.109 (2.77) *1 |
| 40S | 1 (25) |
1.315 (33.4) |
1.68 (2.5) |
0.133 (3.38) |
| 80S | 1 (25) |
1.315 (33.4) |
2.17 (3.24) |
0.179 (4.55) |
| 5S | 1¼ (32) |
1.66 (42.2) |
1.11 (1.65) |
0.065 (1.65) *1 |
| 10S | 1¼ (32) |
1.66 (42.2) |
1.81 (2.69) |
0.109 (2.77) *1 |
| 40S | 1¼ (32) |
1.66 (42.2) |
2.27 (3.39) |
0.14 (3.56) |
| 80S | 1¼ (32) |
1.66 (42.2) |
3.0 (4.47) |
0.191 (4.85) |
| 5S | 1½ (40) |
1.9 (48.3) |
1.28 (1.9) |
0.065 (1.65) *1 |
| 10S | 1½ (40) |
1.9 (48.3) |
2.09 (3.11) |
0.109 (2.77) *1 |
| 40S | 1½ (40) |
1.9 (48.3) |
2.72 (4.05) |
0.145 (3.68) |
| 80S | 1½ (40) |
1.9 (48.3) |
3.63 (5.41) |
0.2 (5.08) |
| 5S | 2 (50) |
2.375 (60.3) |
1.61 (2.39) |
0.065 (1.65) *1 |
| 10S | 2 (50) |
2.375 (60.3) |
2.64 (3.93) |
0.109 (2.77) *1 |
| 40S | 2 (50) |
2.375 (60.3) |
3.66 (5.44) |
0.154 (3.91) |
| 80S | 2 (50) |
2.375 (60.3) |
5.03 (7.48) |
0.218 (5.54) |
| 5S | 2½ (65) |
2.875 (73) |
2.48 (3.69) |
0.083 (2.11) *1 |
| 10S | 2½ (65) |
2.875 (73) |
3.53 (5.26) |
0.12 (3.05) *1 |
| 40S | 2½ (65) |
2.875 (73) |
5.8 (8.63) |
0.203 (5.16) |
| 80S | 2½ (65) |
2.875 (73) |
7.67 (11.41) |
0.276 (7.01) |
| 5S | 3 (80) |
3.5 (88.9) |
3.03 (4.52) |
0.083 (2.11) *1 |
| 10S | 3 (80) |
3.5 (88.9) |
4.34 (6.46) |
0.12 (3.05) *1 |
| 40S | 3 (80) |
3.5 (88.9) |
7.58 (11.29) |
0.216 (5.49) |
| 80S | 3 (80) |
3.5 (88.9) |
10.26 (15.27) |
0.3 (7.62) |
| 5S | 3½ (90) |
4.0 (101.6) |
3.48 (5.18) |
0.083 (2.11) *1 |
| 10S | 3½ (90) |
4.0 (101.6) |
4.98 (7.41) |
0.12 (3.05) *1 |
| 40S | 3½ (90) |
4.0 (101.6) |
9.12 (13.57) |
0.226 (5.74) |
| 80S | 3½ (90) |
4.0 (101.6) |
12.52 (18.64) |
0.318 (8.08) |
| 5S | 4 (100) |
4.5 (114.3) |
3.92 (5.84) |
0.083 (2.11) *1 |
| 10S | 4 (100) |
4.5 (114.3) |
5.62 (8.37) |
0.12 (3.05) *1 |
| 40S | 4 (100) |
4.5 (114.3) |
10.8 (16.08) |
0.237 (6.02) |
| 80S | 4 (100) |
4.5 (114.3) |
15.0 (22.32) |
0.337 (8.56) |
| 5S | 5 (125) |
5.563 (141.3) |
6.36 (9.46) |
0.109 (2.77) *1 |
| 10S | 5 (125) |
5.563 (141.3) |
7.78 (11.56) |
0.134 (3.4) *1 |
| 40S | 5 (125) |
5.563 (141.3) |
14.63 (21.77) |
0.258 (6.55) |
| 80S | 5 (125) |
5.563 (141.3) |
20.8 (30.97) |
0.375 (9.53) |
| 5S | 6 (150) |
6.625 (168.3) |
7.59 (11.31) |
0.109 (2.77) *1 |
| 10S | 6 (150) |
6.625 (168.3) |
9.3 (13.83) |
0.134 (3.4) *1 |
| 40S | 6 (150) |
6.625 (168.3) |
18.99 (28.26) |
0.28 (7.11) |
| 80S | 6 (150) |
6.625 (168.3) |
28.6 (42.56) |
0.432 (10.97) |
| 5S | 8 (200) |
8.625 (219.1) |
9.92 (14.78) |
0.109 (2.77) *1 |
| 10S | 8 (200) |
8.625 (219.1) |
13.41 (19.97) |
0.148 (3.76) *1 |
| 40S | 8 (200) |
8.625 (219.1) |
28.58 (42.55) |
0.322 (8.18) |
| 80S | 8 (200) |
8.625 (219.1) |
43.43 (64.64) |
0.5 (12.7) |
| 5S | 10 (250) |
10.75 (273) |
15.21 (22.61) |
0.134 (3.4) *1 |
| 10S | 10 (250) |
10.75 (273) |
18.67 (27.78) |
0.165 (4.19) *1 |
| 40S | 10 (250) |
10.75 (273) |
40.52 (60.29) |
0.365 (9.27) |
| 80S | 10 (250) |
10.75 (273) |
54.79 (81.53) |
0.5 (12.7) *2 |
| 5S | 12 (300) |
12.75 (323.8) |
21.0 (31.24) |
0.156 (3.96) *1 |
| 10S | 12 (300) |
12.75 (323.8) |
24.19 (35.98) |
0.18 (4.57) *1 |
| 40S | 12 (300) |
12.75 (323.8) |
49.61 (73.86) |
0.375 (9.53) *2 |
| 80S | 12 (300) |
12.75 (323.8) |
65.48 (97.44) |
0.5 (12.7) *2 |
| 5S | 14 (350) |
14.0 (355.6) |
23.09 (34.34) |
0.156 (3.96) *1 |
| 10S | 14 (350) |
14.0 (355.6) |
27.76 (41.36) |
0.188 (4.78) Notes (1),(2) |
| 40S | 14 (350) |
14.0 (355.6) |
54.62 (81.33) |
0.375 (9.53) *2 |
| 80S | 14 (350) |
14.0 (355.6) |
72.16 (107.4) |
0.5 (12.7) *2 |
| 5S | 16 (400) |
16.0 (406.4) |
27.93 (41.56) |
0.165 (4.19) *1 |
| 10S | 16 (400) |
16.0 (406.4) |
31.78 (47.34) |
0.188 (4.78) Notes (1),(2) |
| 40S | 16 (400) |
16.0 (406.4) |
62.64 (93.27) |
0.375 (9.53) *2 |
| 80S | 16 (400) |
16.0 (406.4) |
82.85 (123.31) |
0.5 (12.7) *2 |
| 5S | 18 (450) |
18.0 (457) |
31.46 (46.79) |
0.165 (4.19) *1 |
| 10S | 18 (450) |
18.0 (457) |
35.8 (53.31) |
0.188 (4.78) Notes (1),(2) |
| 40S | 18 (450) |
18.0 (457) |
70.65 (...) |
0.375 (9.53) *2 |
| 80S | 18 (450) |
18.0 (457) |
93.54 (...) |
0.5 (12.7) *2 |
| 5S | 20 (500) |
20.0 (508) |
39.82 (59.32) |
0.188 (4.78) *1 |
| 10S | 20 (500) |
20.0 (508) |
46.1 (68.65) |
0.218 (5.54) Notes (1),(2) |
| 40S | 20 (500) |
20.0 (508) |
78.67 (117.15) |
0.375 (9.53) *2 |
| 80S | 20 (500) |
20.0 (508) |
104.23 (155.13) |
0.5 (12.7) *2 |
| 5S | 22 (550) |
22.0 (559) |
43.84 (65.33) |
0.188 (4.78) *1 |
| 10S | 22 (550) |
22.0 (559) |
50.76 (75.62) |
0.218 (5.54) Notes (1),(2) |
| 40S | 22 (550) |
22.0 (559) |
... | ... |
| 80S | 22 (550) |
22.0 (559) |
... | ... |
| 5S | 24 (600) |
24.0 (610) |
55.42 (82.58) |
0.218 (5.54) *1 |
| 10S | 24 (600) |
24.0 (610) |
63.47 (94.53) |
0.25 (6.35) *1 |
| 40S | 24 (600) |
24.0 (610) |
94.71 (141.12) |
0.375 (9.53) *2 |
| 80S | 24 (600) |
24.0 (610) |
125.61 (187.07) |
0.5 (12.7) *2 |
| 5S | 30 (750) |
30.0 (762) |
79.51 (118.34) |
0.25 (6.35) *1 |
| 10S | 30 (750) |
30.0 (762) |
99.02 (147.29) |
0.312 (7.92) *1 |
| 40S | 30 (750) |
30.0 (762) |
... | ... |
| 80S | 30 (750) |
30.0 (762) |
... | ... |
DN |
OD OF PIPE |
THICKNESS TABLE OF ERW PIPE |
|||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
B SERIES |
A SERIES |
SCH |
SCH |
SCH |
SCH |
LG |
STD |
SCH |
SCH |
SCH |
SCH |
XS |
SCH |
SCH |
SCH |
SCH |
|
32 |
38 |
42.4 |
3.2 |
2.8 |
1.6 |
- |
- |
- |
- |
- |
3.6 |
5.0 |
- |
- |
- |
6.3 |
- |
65 |
76 |
76.1 |
3.6 |
3.0 |
2.0 |
4.5 |
- |
- |
- |
- |
5.0 |
7.1 |
- |
- |
- |
10.0 |
- |
100 |
108 |
114.3 |
4.0 |
3.0 |
2.0 |
5.0 |
- |
- |
- |
- |
5.9 |
8.8 |
- |
11.0 |
- |
14.2 |
- |
200 |
219 |
219.1 |
6.3 |
4.0 |
2.9 |
6.3 |
- |
- |
7.1 |
10.0 |
8.0 |
12.5 |
- |
17.5 |
16.0 |
22.2 |
20.0 |
350 |
377 |
355.6 |
- |
5.0 |
4.0 |
8.0 |
8.0 |
10.0 |
10.0 |
16.0 |
11.0 |
20.0 |
13.0 |
28.0 |
25.8 |
36.0 |
32.0 |
