Table of Contents
- Introduction
- Chemical Composition
- Mechanical Properties
- Physical & Thermal Properties
- Equivalent Grades
- Threaded Flange Details
- Manufacturing Process
- Sizes & Dimensions
- Types Available
- Applications
- Industries Served
- Grade Comparison
- Why BB Infras?
- Certifications & QC
- Export & Packaging
- Threaded Flange Marking
- Coating Options
- Testing Procedure
- Storage Guidelines
- Downloads
- Cities We Supply
- Countries We Export
- FAQ
- People Also Ask
- Related Products
| Material | Carbon Steel (Low Temperature) |
| Grade | ASTM A350 LF2 / ASTM A350 LF2 Cl.1 |
| Standard | ASTM A350 LF2 Cl.1 |
| Type | Threaded Flange |
| Size Range | NPS ½" – 24" (flanges per ASME B16.5) |
| Pressure Class | 150# – 2500# (ASME B16.5) |
| Facing | RF / FF / RTJ |
| Dimensional Std | ASME B16.5 / B16.47 |
| Tensile Strength | 485 MPa min |
| Yield Strength | 250 MPa min |
| MTC | EN 10204 3.1 Mill Test Certificate |
| MOQ | 100 kg (standard sizes) |
Quick Answers
ASTM A350 LF2 Threaded Flange – Overview
ASTM A350 LF2 is a notch-tough carbon steel forging for low-temperature service flanges, fittings and pressure parts. Charpy V-notch impact tests at –46 °C make it essential for cryogenic and cold-climate pipelines.
BB Infras is a leading ASTM A350 LF2 Threaded Flange supplier and exporter based in Mumbai, specialising in low-temperature service components for LNG, cryogenic and cold-climate process plants. Charpy V-notch impact certificates at −46°C are provided with every consignment. ASTM A350 LF2 Threaded 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 ASTM A350 LF2 Threaded Flange?
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Request Quote WhatsAppChemical Composition of ASTM A350 LF2
The following table shows the chemical composition per ASTM A350 LF2 Cl.1.
| C | Mn | P | S | Si | Cu | Ni | Cr | Mo | V |
|---|---|---|---|---|---|---|---|---|---|
| ≤ 0.30 | 0.60–1.35 | ≤ 0.035 | ≤ 0.040 | 0.15–0.40 | ≤ 0.40 | ≤ 0.40 | ≤ 0.30 | ≤ 0.12 | ≤ 0.05 |
Mechanical Properties of ASTM A350 LF2
| Property | Value |
|---|---|
| Tensile Strength | 485 MPa min |
| Yield Strength | 250 MPa min |
| Elongation | 22% min |
| Charpy (–46 °C) | ≥ 27 J |
| Hardness | 197 HB max |
Physical & Thermal Properties
| Property | Value |
|---|---|
| Density | 7.85 g/cm³ |
| Melting Point | 1420–1530 °C |
| Thermal Conductivity | 49 W/m·K |
| Thermal Expansion | 11.7 × 10⁻⁶ /°C |
| Elastic Modulus | 200 GPa |
| Specific Heat | 485 J/kg·K |
| Electrical Resistivity | 0.170 μΩ·m |
Equivalent Grades of ASTM A350 LF2
| Standard Body | Equivalent Grade |
|---|---|
| ASTM | A350 LF2 |
| EN/DIN | P355QH / 16Mo3 |
| UNS | K03012 |
| BS | 1503-223 |
Threaded Flange – Product Details
Applicable Standards: ASME B16.5, ASME B1.20.1 (NPT), BS 21 (BSP)
Manufacturing Process: Forged; bore threaded to ANSI NPT or BSP; face finished RF or FF.
Heat Treatment: Normalise 870–940 °C. Subcritical anneal optional.
ASTM A350 LF2 Threaded Flange – Manufacturing Process
Threaded Flange is produced using a controlled sequence of operations to achieve the dimensional and mechanical requirements of ASTM A350 LF2 Cl.1.
1050–1200 °C
Normalise / Q&T
Face & bore
Per ASME B16.5
ASTM A350 LF2 Threaded Flange – Sizes & Dimensions
Size range: NPS ½" – 24" (flanges per ASME B16.5). The following dimensional data covers standard sizes. Non-standard sizes available on request.
| NPS | Thread Type | Flange OD (mm) | Bolt Circle (mm) | No. Bolts |
|---|---|---|---|---|
| ½" | ½" NPT | 95 | 66.5 | 4 |
| ¾" | ¾" NPT | 113 | 82.5 | 4 |
| 1" | 1" NPT | 125 | 85.7 | 4 |
| 1½" | 1½" NPT | 160 | 114.3 | 4 |
| 2" | 2" NPT | 165 | 127 | 4 |
| 3" | 3" NPT | 210 | 168.3 | 4 |
| 4" | 4" NPT | 254 | 200 | 8 |
Types of ASTM A350 LF2 Threaded Flange
- 150# Threaded Flange
- 300# Threaded Flange
- 600# Threaded Flange
- NPT / BSP variants
Applications of ASTM A350 LF2 Threaded Flange
Industries We Serve
Ready to order ASTM A350 LF2 Threaded Flange?
Stock available in Mumbai. Same-day quotation. Export documentation included.
Email Quote Call NowASTM A350 LF2 – Grade Specification
| Standard | Category | Tensile Strength | Yield Strength | Elongation |
|---|---|---|---|---|
| ASTM A350 LF2 Cl.1 ✓ | Carbon Steel (Low Temperature) | 485 MPa min | 250 MPa min | 22% min |
| ASTM (A350 LF2) | Equivalent | See equivalent grades table above | ||
| EN/DIN (P355QH / 16Mo3) | Equivalent | See equivalent grades table above | ||
| UNS (K03012) | Equivalent | See equivalent grades table above | ||
| BS (1503-223) | Equivalent | See equivalent grades table above | ||
* All values are minimum guaranteed per ASTM A350 LF2 Cl.1. Actual mill certificates may show higher values.
Why Buy ASTM A350 LF2 Threaded Flange from BB Infras?
| Ready Stock | Large inventory of ASTM A350 LF2 Threaded 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 ASTM A350 LF2 Threaded 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 ASTM A350 LF2 Threaded 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
Threaded Flange Marking & Identification
Every ASTM A350 LF2 Threaded Flange supplied by BB Infras is marked per ASTM A350 LF2 Cl.1 and ASME marking requirements. Standard marking sequence:
- Manufacturer name / mark
- Material specification — ASTM A350 LF2 Cl.1
- 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 ASTM A350 LF2 Threaded 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 ASTM A350 LF2 Cl.1 Table 1 |
| 2 | Tensile & Yield Strength | ASTM E8 | ≥485 MPa min / ≥250 MPa min |
| 3 | Elongation | ASTM E8 | ≥22% min |
| 4 | Hardness (HB) | ASTM E10 | Per standard max |
| 5 | Hydrostatic Test | ASTM A350 LF2 Cl.1 / 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.
ASTM A350 LF2 Threaded Flange Supplier in India
BB Infras supplies ASTM A350 LF2 Threaded 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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ASTM A350 LF2 Threaded Flange Exporter – Countries We Ship To
BB Infras exports ASTM A350 LF2 Threaded 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 ASTM A350 LF2 Threaded Flange
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Contact Us Today +91-9152677155People Also Ask
What pressure classes are available for ASTM A350 LF2 Threaded Flange?
ASTM A350 LF2 Threaded 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 ASTM A350 LF2?
Per ASTM A350 LF2 Cl.1: minimum tensile is 485 MPa min and minimum yield is 250 MPa min. Forging heat treatment normalises the material to achieve these values.
Do ASTM A350 LF2 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 ASTM A350 LF2 Threaded 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 |
|---|---|---|
| ASTM A350 LF2 Cl.1 | ASTM / ASME | Material specification for ASTM A350 LF2 |
| 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 |