Table of Contents
- Introduction
- Chemical Composition
- Mechanical Properties
- Physical & Thermal Properties
- Equivalent Grades
- Socket Weld Flange Details
- Manufacturing Process
- Sizes & Dimensions
- Types Available
- Applications
- Industries Served
- Grade Comparison
- Why BB Infras?
- Certifications & QC
- Export & Packaging
- Socket Weld Flange Marking
- Coating Options
- Testing Procedure
- Storage Guidelines
- Downloads
- Cities We Supply
- Countries We Export
- FAQ
- People Also Ask
- Related Products
| Material | Line Pipe Steel |
| Grade | API 5L Grade B / API 5L Gr.B / ISO 3183 |
| Standard | API 5L Gr.B / ISO 3183 |
| Type | Socket Weld Flange |
| Size Range | OD 21.3 mm – 1219 mm; WT SCH 10 to SCH 160 |
| Pressure Class | 150# – 2500# (ASME B16.5) |
| Facing | RF / FF / RTJ |
| Dimensional Std | ASME B16.5 / B16.47 |
| Tensile Strength | 415 MPa min |
| Yield Strength | 245 MPa min |
| MTC | EN 10204 3.1 Mill Test Certificate |
| MOQ | 100 kg (standard sizes) |
Quick Answers
API 5L Grade B Socket Weld Flange – Overview
API 5L Grade B is the baseline carbon steel for oil & gas transmission line pipes. It balances weldability with adequate strength for onshore and offshore pipeline systems in moderate-pressure service.
BB Infras is an established API 5L Grade B Socket Weld Flange supplier to EPC contractors and pipeline operators across India and the Gulf region. We stock both PSL1 and PSL2 grades; sour-service documentation including HIC and SSC test reports is available on request for critical pipeline applications. API 5L Grade B Socket Weld Flange is available in pressure classes 150# to 2500# per ASME B16.5 / B16.47, with raised face (RF), flat face (FF) or ring type joint (RTJ) facing options. Custom bore and custom OD flanges are available on order.
Need a quote for API 5L Grade B Socket Weld Flange?
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Request Quote WhatsAppChemical Composition of API 5L Grade B
The following table shows the chemical composition per API 5L Gr.B / ISO 3183.
| C | Mn | P | S | Si | V | Nb | Ti |
|---|---|---|---|---|---|---|---|
| ≤ 0.28 | ≤ 1.20 | ≤ 0.030 | ≤ 0.030 | ≤ 0.45 | ≤ 0.05 | ≤ 0.05 | ≤ 0.04 |
Mechanical Properties of API 5L Grade B
| Property | Value |
|---|---|
| Tensile Strength | 415 MPa min |
| Yield Strength | 245 MPa min |
| Elongation | 21% min |
| SMYS | 35,500 psi / 245 MPa |
Physical & Thermal Properties
| Property | Value |
|---|---|
| Density | 7.85 g/cm³ |
| Melting Point | 1420–1530 °C |
| Thermal Conductivity | 50 W/m·K |
| Thermal Expansion | 11.9 × 10⁻⁶ /°C |
| Elastic Modulus | 200 GPa |
| Specific Heat | 480 J/kg·K |
| Electrical Resistivity | 0.172 μΩ·m |
Equivalent Grades of API 5L Grade B
| Standard Body | Equivalent Grade |
|---|---|
| API | 5L Gr.B |
| EN ISO 3183 | L245 |
| ASTM | A53 Gr.B / A106 Gr.B |
| IS | 1978 Gr.B |
Socket Weld Flange – Product Details
Applicable Standards: ASME B16.5 (Class 150–2500)
Manufacturing Process: Forged; socket bore drilled 0.8 mm oversize for expansion; single fillet weld per assembly.
Heat Treatment: Normalise or thermo-mechanical controlled rolling (TMCP).
API 5L Grade B Socket Weld Flange – Manufacturing Process
Socket Weld Flange is produced using a controlled sequence of operations to achieve the dimensional and mechanical requirements of API 5L Gr.B / ISO 3183.
1050–1200 °C
Normalise / Q&T
Face & bore
Per ASME B16.5
API 5L Grade B Socket Weld Flange – Sizes & Dimensions
Size range: OD 21.3 mm – 1219 mm; WT SCH 10 to SCH 160. The following dimensional data covers standard sizes. Non-standard sizes available on request.
| NPS | Socket Bore (mm) | Socket Depth (mm) | Flange OD (mm) | No. Bolts |
|---|---|---|---|---|
| ½" | 14.5 | 22 | 95 | 4 |
| ¾" | 19.1 | 25 | 114 | 4 |
| 1" | 22.3 | 29 | 125 | 4 |
| 1½" | 31.8 | 35 | 160 | 4 |
| 2" | 40.9 | 38 | 165 | 4 |
| 2½" | 48.3 | 41 | 190 | 4 |
| 3" | 62.7 | 44 | 210 | 4 |
Types of API 5L Grade B Socket Weld Flange
- 150# SW Flange
- 300# SW Flange
- 600# SW Flange
- 900# SW Flange
- 1500# SW Flange
- 2500# SW Flange
Applications of API 5L Grade B Socket Weld Flange
Industries We Serve
Ready to order API 5L Grade B Socket Weld Flange?
Stock available in Mumbai. Same-day quotation. Export documentation included.
Email Quote Call NowAPI 5L Grade B – Grade Specification
| Standard | Category | Tensile Strength | Yield Strength | Elongation |
|---|---|---|---|---|
| API 5L Gr.B / ISO 3183 ✓ | Line Pipe Steel | 415 MPa min | 245 MPa min | 21% min |
| API (5L Gr.B) | Equivalent | See equivalent grades table above | ||
| EN ISO 3183 (L245) | Equivalent | See equivalent grades table above | ||
| ASTM (A53 Gr.B / A106 Gr.B) | Equivalent | See equivalent grades table above | ||
| IS (1978 Gr.B) | Equivalent | See equivalent grades table above | ||
* All values are minimum guaranteed per API 5L Gr.B / ISO 3183. Actual mill certificates may show higher values.
Why Buy API 5L Grade B Socket Weld Flange from BB Infras?
| Ready Stock | Large inventory of API 5L Grade B Socket Weld Flange in popular sizes maintained in our Mumbai warehouse for immediate dispatch. |
| Certified Material | All material supplied with EN 10204 3.1 Mill Test Certificates from NABL-accredited labs. TPI by SGS, BV, TUV on request. |
| Worldwide Export | We export API 5L Grade B Socket Weld Flange to 80+ countries with complete export documentation — COO, packing list, B/L, fumigation certificates. |
| Competitive Pricing | Direct mill sourcing and bulk buying ensures competitive prices. No middlemen. Transparent pricing with no hidden charges. |
| Fast Delivery | Standard sizes dispatched within 3–5 business days. Custom sizes within 3–4 weeks. Urgent orders accommodated. |
| Value-Added Services | Cut-to-length, bevelling, threading, galvanising, painting, marking & stencilling available in-house. |
| Technical Support | Our metallurgical team assists with grade selection, standard interpretation, and material substitution queries. |
| MSME Registered | Registered MSME supplier. Eligible for GeM portal procurement and government tenders. |
Certifications & Quality Inspection
Every API 5L Grade B Socket Weld Flange supplied by BB Infras undergoes the following quality controls:
Quality Inspection Checklist
- Chemical composition analysis (OES / wet analysis)
- Mechanical testing: tensile, yield, elongation, impact
- Dimensional inspection per applicable ASME standard
- Visual and surface finish inspection
- Hydrostatic or pneumatic pressure testing
- Non-Destructive Testing: UT, RT, MT, PT on request
- Positive Material Identification (PMI) on request
Export Packaging & MOQ
- Minimum Order Quantity (MOQ): 100 kg or 1 piece (standard sizes); 500 kg for custom sizes
- Packing for Pipes/Tubes: Bundled with steel strapping, plastic end caps, moisture-proof wrapping
- Packing for Fittings/Flanges: Wooden box / wooden pallet, plywood case for heavy items
- Sea Freight: FCL / LCL container, fumigation certificate provided
- Air Freight: Available for urgent requirements
- Documents: Commercial Invoice, Packing List, Certificate of Origin, MTC, Bill of Lading, Insurance Certificate
- Marking: Heat number, grade, size, schedule, standard per ASTM A5.40 / ASME marking requirements
Socket Weld Flange Marking & Identification
Every API 5L Grade B Socket Weld Flange supplied by BB Infras is marked per API 5L Gr.B / ISO 3183 and ASME marking requirements. Standard marking sequence:
- Manufacturer name / mark
- Material specification — API 5L Gr.B
- Pressure class — 150# / 300# / etc.
- NPS size
- Facing type — RF / FF / RTJ
- Heat / lot number — for MTC traceability
Coating & Surface Finish Options
| Coating Type | Standard | Application | Lead Time |
|---|---|---|---|
| Mill Finish / Black Paint | Per standard | General process service | In Stock |
| Yellow Zinc Chromate Primer | — | Corrosion protection in transit | In Stock |
| Hot-Dipped Galvanised (HDG) | ASTM A123 | Plumbing & utility service | 3–5 days |
| Two-Coat Epoxy Paint | — | Offshore & chemical plant | 1–2 weeks |
Testing & Inspection Procedure
All API 5L Grade B Socket Weld Flange supplied by BB Infras undergo a multi-stage inspection and testing process before dispatch:
| # | Test / Inspection | Standard / Method | Acceptance |
|---|---|---|---|
| 1 | Chemical Composition (OES) | ASTM E415 | Per API 5L Gr.B Table 1 |
| 2 | Tensile & Yield Strength | ASTM E8 | ≥415 MPa min / ≥245 MPa min |
| 3 | Elongation | ASTM E8 | ≥21% min |
| 4 | Hardness (HB) | ASTM E10 | Per standard max |
| 5 | Hydrostatic Test | API 5L Gr.B / ASME B31.3 | Leak-free at test pressure |
| 6 | Dimensional Inspection | ASME B16.5 | Within tolerance |
| 7 | Visual & Surface | ASTM A530 / MSS SP-55 | Free from defects |
| 8 | Ultrasonic Testing (UT) | ASTM E213 (on request) | No sub-surface defects |
| 9 | PMI (XRF) | ASTM E1476 (on request) | Grade confirmation |
Storage & Handling Guidelines
- Store on wooden dunnage or pipe racks — never directly on concrete to avoid moisture-induced corrosion.
- Stack with appropriate separators; observe safe stack heights to prevent deformation.
- Apply plastic end caps or plugs to all open ends to prevent ingress of moisture, dust and insects.
- Keep material dry and ventilated; store under cover in humid or coastal climates.
- Use nylon slings or padded lifting hooks — never bare wire rope directly on surface.
- For long-term storage (>6 months), re-apply protective oil coating or wrap with VCI (Vapour Corrosion Inhibitor) film.
- Identify items with heat number tags throughout storage for full MTC traceability.
Downloads & Technical Resources
Request product documentation from our technical team. Available on enquiry:
Contact our technical team with your enquiry details and we will share the relevant document within 24 hours.
API 5L Grade B Socket Weld Flange Supplier in India
BB Infras supplies API 5L Grade B Socket Weld Flange to customers across India from our Mumbai stockyard. We serve all major industrial hubs — refineries in Jamnagar and Haldia, petrochemical clusters in Dahej and Panipat, shipyards in Kochi and Visakhapatnam, and fabrication workshops across Pune, Rajkot, Surat and Coimbatore — with same-day quotation and fast dispatch.
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API 5L Grade B Socket Weld Flange Exporter – Countries We Ship To
BB Infras exports API 5L Grade B Socket Weld Flange to 80+ countries with complete export documentation — Certificate of Origin, Material Test Certificate, Packing List, Bill of Lading and Fumigation Certificate. We are a trusted exporter to UAE, Saudi Arabia, Qatar, Oman and Kuwait in the Middle East; to Singapore, Malaysia, Indonesia and Vietnam in Southeast Asia; to South Africa, Nigeria and Kenya in Africa; and to the USA, UK, Germany and Netherlands in Europe and North America.
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Frequently Asked Questions
Get the best price for API 5L Grade B Socket Weld Flange
Talk to our sales team — available Mon–Sat, 9 AM – 7 PM IST. Same-day quotes.
Contact Us Today +91-9152677155People Also Ask
What pressure classes are available for API 5L Grade B Socket Weld Flange?
API 5L Grade B Socket Weld Flange is available in 150#, 300#, 600#, 900#, 1500# and 2500# per ASME B16.5. For NPS > 24", ASME B16.47 Series A/B applies.
What facing options are available?
Available facings: Raised Face (RF), Flat Face (FF) and Ring Type Joint (RTJ). RF is the most common for general service.
What is the tensile and yield strength of API 5L Grade B?
Per API 5L Gr.B: minimum tensile is 415 MPa min and minimum yield is 245 MPa min. Forging heat treatment normalises the material to achieve these values.
Do API 5L Grade B flanges need PWHT after welding?
PWHT requirements depend on wall thickness and service per ASME B31.3 Section 331. For carbon steel flanges, PWHT typically applies for wall thickness above 19 mm or as specified by the engineer.
What is the price of API 5L Grade B Socket Weld Flange in India?
Prices vary by size, pressure class, quantity and market rates. Contact BB Infras for a firm quotation from our Mumbai stockyard.
Authoritative Standards Referenced
| Standard | Issuing Body | Scope |
|---|---|---|
| API 5L Gr.B / ISO 3183 | ASTM / ASME | Material specification for API 5L Grade B |
| ASME B16.5 | ASME | Pipe flanges and flanged fittings — NPS ½" – 24" |
| ASME B16.47 | ASME | Large diameter steel flanges — NPS 26" – 60" |
| EN 10204:2004 | CEN | Metallic products — types of inspection documents (3.1 MTC) |
| NACE MR0175 / ISO 15156 | NACE/ISO | Materials for H₂S service in oil and gas production |