API 5L Grade B pipes are standard grade pipes that are seen most in the application at oil and gas-based industries. This grade of pipes is most notably characterized by their durable nature and cost-effectiveness.
Also known as L245 pipe, API 5L Grade B pipes come in PSL1, PSL2, and sour services used in production and delivery operations. API 5L Grade B pipes commonly refer to a category of both welded and seamless pipes that are used in businesses dealing with the transmission of oil and natural gases. Industries employing such pipes include gas and oil plants and refineries.
- Product Description
The API 5L is a common standard of pipelines that has a wide field of applications in various services like transmission and construction.
Among the three grades of API 5L - A, B, and X, Grade B is the most widely used type. They come in both seamless and welded pipes and are employed for offshore and onshore purposes.
Due to their remarkable durability and endurance, these grades of pipelines are considered to be ideal for projects that work in extreme temperatures and pressure. They are also preferred by both sellers and clients because of their cost-effectiveness and easy availability.
- Properties of API 5L Grade B Line Pipe
The properties and qualities of API 5L Grade B Line Pipe are analyzed based on their chemical composition as well as mechanical traits. Here, a summarized version of both of these factors is given.
2.1) Chemical Composition
The chemical properties of API 5L Grade B Line Pipes are primarily based on carbon content along with the quantity of some other basic elements.
Chemical Composition of API 5L Grade B PSL1 (Seamless Pipes)
| Steel Type | Mass Fraction According to Heat and Product Data (%) | ||||||
| C (Max b) | Ti (Max) | Mn (Max b) | Nb (Max) | P (Max) | V (Max) | S (Max) | |
| B | 0.28 | d | 1.2 | c, d | 0.3 | c, d | 0.3 |
Chemical Composition of API 5L Grade B PSL1 (Welded Pipes)
| Steel Type | Mass Fraction According to Heat and Product Data (%) | ||||||
| C (Max b) | Ti (Max) | Mn (Max b) | Nb (Max) | P (Max) | V (Max) | S (Max) | |
| B | 0.26 | d | 1.2 | c, d | 0.3 | c, d | 0.3 |
Note: These chemical composition estimates are only applicable when t is less than or equal to 0.984".
Chemical Composition of API 5L Grade B PSL2 (Seamless Pipes)
| Steel Type | Mass Fraction According to Heat and Product Data (%) | Carbon Equivalent (a) | |||||||||
| C (Max b) | Ti (Max) | Mn (Max b) | Nb (Max) | P (Max) | V (Max) | S (Max) | Si (Max) | Other | CE Pcm (Max) | CE IIW (Max) | |
| BR | 0.24 | 0.04 | 1.2 | c | 0.025 | c | 0.015 | 0.4 | e, l | 0.25 | 0.43 |
| BQ | 0.18 | 0.04 | 1.4 | 0.5 | 0.025 | 0.5 | 0.015 | 0.45 | e, l | 0.25 | 0.43 |
| BN | 0.24 | 0.04 | 1.2 | c | 0.025 | c | 0.015 | 0.4 | e, l | 0.25 | 0.43 |
Chemical Composition of API 5L Grade B PSL1 (Welded Pipes)
| Steel Type | Mass Fraction According to Heat and Product Data (%) | Carbon Equivalent (a) | |||||||||
| C (Max b) | Ti (Max) | Mn (Max b) | Nb (Max) | P (Max) | V (Max) | S (Max) | Si (Max) | Other | CE Pcm (Max) | CE IIW (Max) | |
| BM | 0.22 | 0.04 | 1.2 | 0.05 | 0.025 | 0.05 | 0.015 | 0.45 | e, l | 0.25 | 0.43 |
Note: These chemical composition estimates are only applicable when t is less than or equal to 0.984".
The charts demonstrate the chemical contents of API 5L Grade B PSL1 and PSL2 (seamless and welded) pipes. The primary point of distinction in their composition is notably C (carbon), along with a few contrasts in the number of other elements.
2.2) Mechanical Properties
Apart from the chemical composition, the two categories of API 5L Grade B Line Pipes are recognized by their mechanical characteristics.
Mechanical Characteristics of API 5L Grade B PSL1
| Steel Type | Tensile Properties for Both Seamless and Welded Pipes | Welded Pipe Seam | ||
| Tensile Strength a (RM Psi Min) | Yield Strength a (Rt0, 5 Psi Min) | Elongation (In 2in Af % min) | Tensile Strength b (RM Psi Min) | |
| L245 or B | 60,200 | 35,500 | c | 60,200 |
Mechanical Characteristics of API 5L Grade B PSL2
| Steel Type | Tensile Properties for Both Seamless and Welded Pipes | Welded Pipe Seam | |||
| Tensile Strength a (RM Psi Min) | Yield Strength a (Rt0, 5 Psi Min) | Elongation (In 2in Af % min) | Ratio a, c R10, 5IRm | Tensile Strength d (RM Psi Min) | |
| BR, BM, BQ, BN | 60,200 (Min) 95,000 (Max) | 35,500 (Min) 65,300 (Max) | f (Min) | 0.93 (Max) | 60,200 (Min) |
- Equivalent Materials
The equivalents for API 5L Grade B Line pipes are considered to be ASTM A106 B or ASTM A53 B. The PSL1 type is considered to be the closest equivalent to them.
It is because this particular grade also possesses chemical content, mechanical traits, and uses that resemble that of API 5L Grade B.
- API 5L Grade B Line Pipe Types
The API 5L Grade B line pipes are broadly categorized into PSL1 and PSL2 along with sour service type.
These grades of pipes are manufactured in two varieties - seamless and welded for offshore and onshore works along with sour service.
- Testing Methods
The following testing methods are applicable for API 5L Grade B pipelines:
- Hydrostatic Test
- Bend Test
- Flattening Test
- Guided-Bend Test
- DWT test, and CVN impact test (for PSL2 pipes)
- Use and Application
The use of API 5L Grade B line pipes is most commonly seen in a diverse range of industries and businesses. They are:
- Oil and gas trades (petrochemical factories and refineries)
- Industrial commerce (steel mills and pharmaceutical plants)
- Water supply (transmission pipes, pumping stations, dams, and irrigation tubes)
- Alternative energy (thermal and hydroelectric power plants)
- Conclusion
The API 5L Grade B grades are one of the most used and preferred forms of materials for a wide range of applications. Mostly seen and utilized for oil and gas transmission, these pipes are particularly noted for their durability and cost-effectiveness.
Their anti-cracking properties and long life make the Grade B pipes specifically popular for sour service as well as petroleum and gas transportation.