
API 5L Line Pipe Application:
API 5L is a specification of API (The American Petroleum Institute) which defines the standard for the dimension, physical, mechanical and chemical properties of the steel. API Line Pipe is used for the transmission of gas, water, and oil.
API 5L Line Pipe Grades
The API 5L specification covers seamless and welded pipes to convey oil, gas, water in the natural oil & gas and petrochemical industries. API 5L line pipes are available in multiple carbon steel grades, designated as Grade B, X42, X46, X52, X56, X60, X70, X80, and in PSL1 or PSL2 specification levels.



API 5L PSL1 VS. API 5L PSL2
API 5L PSL1 and PSL2 are two specification levels that differ in terms of chemical composition and test requirements. The differences between PSL1 and PSL2 are outlined in the two tables below:
PSL GRADE | C, a | Mn a | P | S | Si | V | Nb | Ti | Other | CEIIW | CEpcm |
1 | 0.24 | 1.4 | ##### | ###### | 0.45 | 0.1 | 0.05 | 0.04 | b,c | 0.043 | 0.025 |
2 | 0.28 | 1.4 | 0.03 | 0.03 | – | b | b | b | – | – | – |
Test Requirement | API 5L PSL1 | API 5L PSL2 |
Charpy test | None required | Required for all grades |
Seamless NDT test | Only if purchaser specifies SR4 | SR4 mandatory |
Certification | Certificates when specified per SR15 | Certificates (SR 15.1) mandatory |
Traceability | Traceable only until all tests are passed, unless SR15 is specified | Traceable after completion of tests (SR 15.2) mandatory |
Hydrostatic Test | Required | Required |
Introduction to Seamless Steel Pipe Manufacturing
How are seamless steel pipes made? In general, there are three steps involved in making a seamless steel pipe. First is to convert the raw material into workable form. Next, to form the shape of the pipe in a production line. Third, the pipe is cut and modified to meet the customer’s needs.

In the first step, the round billet is heated to a certain degree in a rotary hearth furnace, then got transferred to the piercing mill to be pierced through the center to form a hollow shell. During the next step, the hollow shell will be rolled by a mandrel mill to reduce the outside diameter and wall thickness which could elongate the pipe. In the stretching mill, the elongated tube will be reheated and further reduced to specified dimensions. At last, the pipe will be thoroughly quenched, cut, and subjected to final inspection.
API 5L PIPE PSL1 Chemical and Mechanical Properties
API 5L PIPE PSL1 | Chemical Composition | Mechanical Property | |||||||
C (Max) | Mn (Max) | P (Max) | S (Max) | TENSILE ( Min ) | YIELD ( Min ) | ||||
Psi X 1000 | Mpa | Psi X 1000 | Mpa | ||||||
Grade A25 | CL I | 0.21 | 0.6 | 0.03 | 0.03 | 45 | 310 | 25 | 172 |
CL II | 0.21 | 0.6 | 0.03 | 0.03 | |||||
Grade A | 0.22 | 0.9 | 0.03 | 0.03 | 48 | 331 | 30 | 207 | |
Grade B | 0.26 | 1.2 | 0.03 | 0.03 | 60 | 414 | 35 | 241 | |
Grade X42 | 0.26 | 1.3 | 0.03 | 0.03 | 60 | 414 | 42 | 290 | |
Grade X46 | 0.26 | 1.4 | 0.03 | 0.03 | 63 | 434 | 46 | 317 | |
Grade X52 | 0.26 | 1.4 | 0.03 | 0.03 | 66 | 455 | 52 | 359 | |
Grade X56 | 0.26 | 1.4 | 0.03 | 0.03 | 71 | 490 | 56 | 386 | |
Grade X60 | 0.26 | 1.4 | 0.03 | 0.03 | 75 | 517 | 60 | 414 | |
Grade X65 | 0.26 | 1.45 | 0.03 | 0.03 | 77 | 531 | 65 | 448 | |
Grade X70 | 0.26 | 1.65 | 0.03 | 0.03 | 82 | 565 | 70 | 483 |
API 5L PIPE | Chemical Composition | Mechanical Property | ||||||||||
PSL2 | C | Mn | P | S | Tensile | Yield | C. E. IMPACT ENERGY | |||||
(Max) | (Max) | (Max) | (Max) | Psi x 1000 | Mpa | Psi x 1000 | Mpa | PCM | IIW | J | FT/LB | |
Grade B | 0.22 | 1.2 | 0.025 | 0.015 | 60 – 110 | 414 – 758 | 35 – 65 | 241 – 448 | 0.25 | 0.43 | T/L 27/41 | T/L 20/30 |
Grade X42 | 0.22 | 1.3 | 0.025 | 0.015 | 60 – 110 | 414 – 758 | 42 – 72 | 290 – 496 | 0.25 | 0.43 | T/L 27/41 | T/L 20/30 |
Grade X46 | 0.22 | 1.4 | 0.025 | 0.015 | 63 – 110 | 434 – 758 | 46 – 76 | 317 – 524 | 0.25 | 0.43 | T/L 27/41 | T/L 20/30 |
Grade X52 | 0.22 | 1.4 | 0.025 | 0.015 | 66 – 110 | 455 – 758 | 52 – 77 | 359 – 531 | 0.25 | 0.43 | T/L 27/41 | T/L 20/30 |
Grade X56 | 0.22 | 1.4 | 0.025 | 0.015 | 71 – 110 | 490 – 758 | 56 – 79 | 386 – 544 | 0.25 | 0.43 | T/L 27/41 | T/L 20/30 |
Grade X60 | 0.22 | 1.4 | 0.025 | 0.015 | 75 – 110 | 517 – 758 | 60 – 82 | 414 – 565 | 0.25 | 0.43 | T/L 27/41 | T/L 20/30 |
Grade X65 | 0.22 | 1.45 | 0.025 | 0.015 | 77 – 110 | 531 – 758 | 65 – 82 | 448 – 565 | 0.25 | 0.43 | T/L 27/41 | T/L 20/30 |
Grade X70 | 0.22 | 1.65 | 0.025 | 0.015 | 82 – 110 | 565 – 758 | 70 – 82 | 483 – 565 | 0.25 | 0.43 | T/L 27/41 | T/L 20/30 |
Grade X80 | 0.22 | 1.9 | 0.025 | 0.015 | 90 – 120 | 621 – 827 | 80 – 102 | 552 – 705 | 0.25 | 0.43 | T/L 27/41 | T/L 20/30 |