The American Petroleum Institute’s (API) API 5L standard covers line pipe levels. The standard has different levels that specify different requirements for the manufacture of line pipes. PSL-1 is the most basic level and covers the simplest requirements. PSL-2 has progressively stricter requirements. All levels require test to ensure that the line pipes meet the required standards. The PSL-1 level is the most basic and is therefore less strictly regulated than the other levels. However, all levels are still subject to strict quality control measures to ensure that only the highest quality line pipes are manufactured.

The API committee establishes standards for these pipes, which are required by the majority of energy firms. PSL-1 and PSL-2 are standards that have been implemented to assist with the more stringent requirements for each grade level. These two fundamental criteria are acknowledged as having differing levels of physical and technical requirements.

Table of Contents

What is the Difference between API 5L PSL-1 and PSL-2?

The American Petroleum Institute (API) classifies oil and gas field pipelines according to their levels of quality. The two levels are PSL-1 and PSL-2. The main difference between the two levels is that PSL-2 has stricter requirements in terms of testing and properties. To be classified as PSL-2, a pipeline must meet certain standards for chemical composition, mechanical properties (tensile strength, yield strength, elongation), and weld seam quality. In addition, test frequency must be increased to ensure that the pipeline meets all requirements. As a result, PSL-2 pipelines are typical of a higher quality than PSL-1 pipelines.

Chemical Composition for API 5L PSL-1 Pipe with t ≤ 0.984”

Chemical Composition of API 5L PSL-1 Line Pipe

API 5L PSL-1 Line Pipe Mechanical Properties

Tensile Test API 5L PSL 1 Line Pipe

Dimensions and Sizes of API 5L PSL-1 Line Pipe

When specifying a line pipe for an application, it is important to check that the dimensions and masses of the pipe meet the required standards. For example, the dimensions and masses of API 5L PSL-1 line pipes are specified in ISO 4200 and ASME B36.10M. These standards provide a guide for different size pipes and specify the wall thickness of each size. Checking that a particular pipe meets the required standards can be done by referring to these tables. Doing so helps to ensure that the pipe is the right size and has the correct wall thickness. This is important because using a pipe that does not meet the required standards can lead to problems such as poor performance or even failure.


Delivery Conditions for API 5L PSL-1 Pipes

PSLDelivery conditions for API 5L PSL-1 Steel PipeSteel grade
PSL -1As rolled, normalizing rolled, thermomechanical rolled/formed, normalizing formed, normalized, and tempered; if agreed, quenched and tempered for SMLS pipe onlyB
As rolled, normalizing rolled, thermomechanical rolled/formed, normalizing formed, normalized and tempered or quenched and temperedX42, X46, X52, X56, X60, X65, X70

Test and inspection of API 5L PSL-1 Line pipes

- Hydrostatic Test

Hydrostatic testing is a critical quality control step in the production of pipelines. The test is conducted by filling the pipeline with water and then applying pressure to the water. This pressure stimulates the operational pressure that the pipeline will experience once it is in service. If there are any leaks in the weld seams or the pipe body, they will be revealed by the hydrostatic test. As a result, hydrostatic testing is an essential part of ensuring the safety and quality of pipelines.

- Bend Test

In pipeline production, a bend test is used to check for any cracks or defects in the metals being used. A sample of the metal is placed under stress and then bent to see if any cracks appear. If there are any cracks, they will be repaired before the metal is used in the construction of the pipeline. The bend test is an important part of quality control in pipeline production, as it ensures that the materials being used are strong and free from defects.

- Flattening Test

A flattening test is a type of crack-propagation test typically used to determine the crack-arrest performance of pipeline steels. The test involves applying a longitudinal or circumferential crack to a pre-cracked specimen and then subjecting the specimen to an increasing applied load until failure occurs. During testing, the crack is monitored for propagation and the applied stress and deformation of the specimen are recorded. The results of the flattening test can be used to evaluate the crack-arrest performance of pipeline steels under various loading conditions.

- CVN Impact Test

An impact test is a type of mechanical test that provides information about the toughness and ductility of materials. The test involves delivering a blow to a sample of the material under controlled conditions. The resulting deformation of the sample is then measured and analyzed. Impact tests are commonly used in the pipeline industry to assess the performance of pipe materials. The three main areas of focus in impact testing are the pipe body, weld seam, and heat-affected zone. By understanding how these areas respond to impact, engineers can optimize pipeline design and ensure safe and reliable operation.


DWTT is an impact test used to determine the ductility of a material. The test is performed by impact loading a material specimen, such as a pipeline, at a specified temperature. The resulting impact energy is then measured and used to calculate the DWTT of the material. The DWTT is an important parameter in the design of pipelines and other large diameter products, as it provides insight into the impact strength of the material. In general, materials with high DWTT values are more resistant to impact damage and are better suited for use in high-pressure applications. As such, the DWTT is an important tool in the production of pipelines and other large diameter products.


Slotted Liner
Steel Fabrication
Pipe Fittings
Scroll to Top

Get A Quote Now

Fill in the form below and our team will be happy to assist you