API 5L Grade B Pipe Specification

API 5L Grade B (also known as L245) is one of the most frequently purchased carbon steel API 5L line pipe grades for oil, gas, and liquid transmission projects. This page helps buyers and engineers quickly confirm PSL1 vs PSL2 vs Sour Service, pick the right manufacturing type (Seamless / ERW / LSAW / SSAW/HSAW), and prepare an RFQ/PO that reduces rework during inspection and receiving.

If you share your OD × WT, PSL level, delivery condition (suffix letter), and coating requirement, we can quote Grade B (L245) with an inspection/document package aligned to your project ITP.

Quick Navigation

• API 5L Grade B Overview (L245)
• PSL1 vs PSL2 vs Sour Service Type
• Suffix Letter
• Seamless and Welded (ERW, LSAW, SSAW/HSAW) Types
• API 5L Grade B vs ASTM A106 B vs ASTM A53 B
• Chemical Composition & Mechanical Properties (PSL1 / PSL2)
• RFQ / PO Checklist
• Inspection & Documentation Package
• FAQ

API 5L Grade B pipe is a common grade pipe for oil and gas pipeline transmissions. It also called L245 Pipe refer ISO 3183, named by minimum yield strength 245 Mpa (35,500 Psi). Equivalent material ASTM A106 B or ASTM A53 B, which have similar value on chemical composition, mechanical properties, and applications.

API 5L B covers PSL1, PSL2, Sour Services, for onshore and offshore pipelines. Manufacturing types including seamless and welded.

PSL1, PSL2 and Sour Service Type

PSL1 is generally use which equivalent to ASTM A106 B and A53 B.

PSL2 is a higher specificaiton level pipe, has more strict value on chemical and mechanical strenth. More over PSL2 requires more test methods like None Distructive Test, CVN Impact Test, DWT etc.
API 5L B PSL2 expressed with API 5L BN/Q/R/M

Sour Services: For sour pipelines like H2S environment, pipe material have typical resrictions on chemicals element of Carbon, P and S. Referring standard NACE MR0175.

API 5L B Pipe for Sour Service expressed in API 5L BNS/QS/MS

Procurement note: PSL level and testing scope are often defined by project ITP. To avoid mismatch during inspection, confirm PSL + suffix + test/document package in the RFQ/PO.

Suffix Letter

Suffix letter specified the pipe delivery condition:

R: As rolled
N: Normalizing rolled, Normalized formed, Normalized
Q: Tempered and quenched
M: Thermomechanical rolled or thermomechanical formed
S: Sour Services, comes with PSL2 pipe with for NS, QS, MS, eg API 5L Grade B NS, API 5L B QS

How to write it in a PO (example): API 5L Grade B PSL2 BN (or BQS for sour service), Seamless/ERW/LSAW/SSAW, OD × WT, length, ends, coating, and required inspection documents.

Seamless and Welded (ERW, LSAW, SSAW/HSAW) Types

Seamless Type: Including hot rolled seamless for pipe diameter above 3 inch, cold rolled seamless below 3 inch.

ERW Welded Type: Electric Resistance Welded, for pipe diameter below 24 inch.

LSAW Type: Longitudinal Sub-merged Arc Welding, for pipe OD 20 inch to 48 inch. LSAW also called JCOE, it means pipe manufacturing shapes from J shape, C shape, O shape, and then cold expanding.

SSAW/HSAW Type:  Spiral Sub-merged Arc Welding or Helical SAW, for pipe OD up to 100 inch.

How to Choose a Manufacturing Type

• Seamless: commonly chosen when the project prefers a weld-seam-free pipe body and sizes fall within seamless range.
• ERW: often used for smaller to medium diameters where production consistency is important.
• LSAW (JCOE): frequently selected for larger OD where longitudinal weld inspection controls are required by project acceptance
• SSAW/HSAW: commonly used for very large OD; confirm the project acceptance criteria and NDT plan early.

API 5L Grade B Pipe is Most Common Use Material

API 5L Grade B, ASTM A106 Grade B and A53 B, these three are most common use material for the industries where refers pipeline construction or oil and gas, liquid transmissions.

When API 5L Grade B Is the Right Choice (vs ASTM A106 B / ASTM A53 B)

• API 5L Grade B: typically specified for line pipe / pipeline transmission projects where PSL level, traceability, and acceptance testing are key procurement items.
• ASTM A106 B: commonly referenced for seamless pipe used in pressure/high-temperature service conditions.
• ASTM A53 B: covers welded and seamless general-purpose steel pipe and may include galvanized supply depending on requirement.

ASTM 106 pipe refers to the carbon steel pipe manufactured in hot rolled or cold drawn (rolled) seamless.

ASTM A53 pipe covers welded and seamless steel pipe, in carbon black material and some cases in hot dipped galvanized (zinc coated).

Difference Amoung API 5L Grade B, ASTM A106 Grade B, ASTM A53 Grade B, more details view here.

API 5L Grade B Pipe Data Sheet

API 5L Grade B Data Sheet Download

API 5L Grade B Pipe PSL1 Chemical Composition

a. Cu ≤ 0.50%; Ni ≤ 0.50% and Mo ≤ 0.15 %
b. For 0.01% reduce of maximum carbon, an increase of 0.05% Mn is permitted, up tp a maximum of 1.65% for grade ≥ L245 or B, but ≤ L360 or X52; up to a maximum of 1.75% for grade > L360 or X52, but < L485 or X70; and up to a maximum of 2.00% for grade L485 or X70.
c. Nb + V 0.06% unless agreed.
d. Nb + V + Ti ≤ 0.15% unless otherwise agreed.
e. Unless otherwise agreed.
f. Unless otherwise agreed, Nb + V + Ti ≤ 0.001%
g. No deliberate addition of B is permitted and the residual B ≤ 0.001%.

Mechnical Properties

a. For intermediate grades, the difference between the specified minimum tensile strength and minimum yield strength for the pipe body shall be as given in the table for the next higher grade.
b. For intermediate grades, the specified minimum tensile strength for the weld seam shall be the same value as was
determined for the pipe body ung footnote a)
c. The specified minimum elongation, Af, expressed in percent and rounded to the nearest percent, shall be as
determined using the following equation:

How to Use Chemical & Mechanical Tables in Procurement

When placing an order for API 5L Grade B, confirm that the MTC lists heat number traceability and shows chemical/mechanical results aligned to your required PSL level. For PSL2 and sour service projects, confirm any required NDT / CVN / DWT scope and the reporting format required by your ITP.

API 5L Grade B PSL2 Pipe Specification

Chemical Composition

Mechanical Properties

For API 5L B Sour Services Pipe Specifications please view here.

Our Supply Range

Octal offers API 5L B seamless carbon steel line pipe, product specification level in PSL 1 and PSL 2, and for sour services.

Attached below with our supply range for API 5L Grade B Pipe:
Grade: API 5L Grade BN/Q/M/NS/QS/MS
Manufacturing type: Seamless and welded ERW, LSAW, SSAW/HSAW
Outer Diameters for Seamless: 1/2” – 24”
OD for ERW: up to 24”
OD for LSAW: 16” to 48”
OD for SSAW/HSAW: up to 100”
Range of Thickness: Sch 20, SCH 40, SCH STD, SCH 80, SCH XS, SCH 120, SCH XXS, SCH 160
Range of Length: SRL, DRL, 20FT, 40FT
Product Specification Level: PSL1, PSL2, Sour Services
Ends: Plain, Beveled, Threaded
Coating Available: FBE, 3PE/3LPE, Black Painting, Varnished, Anti-rust oil, Galvanized, CRA, CWC

Typical Inspection & Documentation Package

Below is a practical document set commonly requested for API 5L Grade B line pipe projects (final scope depends on PSL level and project ITP):

MTC (Mill Test Certificate) with heat number traceability
Dimensional inspection report (OD/WT/length/end condition)
NDT report (UT/RT) when specified
Mechanical test reports; CVN / DWT where specified
Coating report (DFT/holiday test/adhesion items depending on coating system)
Marking & traceability record (heat/lot mapping)
Packing list + shipping marks

FAQ

Q1: What is API 5L Grade B (L245) pipe used for?
A1: It is commonly specified for oil, gas, and liquid transmission pipelines. Grade B (L245) is widely used for onshore/offshore line pipe projects depending on PSL level and project acceptance requirements.

Q2: What’s the difference between API 5L PSL1 and PSL2 for Grade B?
A2: PSL2 generally applies tighter chemical/mechanical limits and may require additional testing such as NDT, CVN impact testing, and DWT when specified by the project. PSL1 follows baseline requirements for general pipeline procurement.

Q3: How do I choose Seamless vs ERW vs LSAW vs SSAW/HSAW for API 5L Grade B?
A3: Start with required OD range and project acceptance criteria. Seamless and welded routes are both available; align the manufacturing type with size range, inspection/testing scope, and the documentation required by your project ITP.

Q4: How should I write a PO/RFQ for API 5L line pipe to avoid rework?
A4: Specify API 5L grade (B/L245), PSL (PSL1/PSL2), suffix/delivery condition (BN/BQ/BR/BM and “S” for sour service where applicable), manufacturing type, OD × WT (or NPS & schedule), length, end condition, coating, and required inspection/document package (MTC + NDT/impact reports as required).

View here for API 5L pipe specifications

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