Table of Contents
- Introduction
- Chemical Composition
- Mechanical Properties
- Physical & Thermal Properties
- Equivalent Grades
- Spectacle Blind Flange Details
- Manufacturing Process
- Sizes & Dimensions
- Types Available
- Applications
- Industries Served
- Grade Comparison
- Why BB Infras?
- Certifications & QC
- Export & Packaging
- Spectacle Blind Flange Marking
- Coating Options
- Testing Procedure
- Storage Guidelines
- Downloads
- Cities We Supply
- Countries We Export
- FAQ
- People Also Ask
- Related Products
| Material | Medium Carbon Steel |
| Grade | EN8 / BS 970 080M40 (EN8) |
| Standard | BS 970 080M40 (EN8) |
| Type | Spectacle Blind Flange |
| Size Range | Bars Ø 6–250 mm; flats, hexes, plates |
| Pressure Class | 150# – 2500# (ASME B16.5) |
| Facing | RF / FF / RTJ |
| Dimensional Std | ASME B16.5 / B16.47 |
| Tensile Strength | 550–700 MPa (N) |
| Yield Strength | 290 MPa min |
| MTC | EN 10204 3.1 Mill Test Certificate |
| MOQ | 100 kg (standard sizes) |
Quick Answers
EN8 Spectacle Blind Flange – Overview
EN8 (080M40) is a widely used medium carbon steel offering good tensile strength in the normalised condition and outstanding strength after heat treatment. Suitable for general engineering uses where surface hardness is required.
BB Infras stocks EN8 Spectacle Blind Flange in rounds, hexagonals and profiles from leading Indian and European mills, regularly supplied to gear manufacturers, machine builders and automotive component suppliers with hardness and impact test reports on request. EN8 Spectacle Blind 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.
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Request Quote WhatsAppChemical Composition of EN8
The following table shows the chemical composition per BS 970 080M40 (EN8).
| C | Mn | Si | P | S |
|---|---|---|---|---|
| 0.36–0.44 | 0.60–1.00 | 0.10–0.40 | ≤ 0.040 | ≤ 0.040 |
Mechanical Properties of EN8
| Property | Value |
|---|---|
| Tensile Strength | 550–700 MPa (N) |
| Yield Strength | 290 MPa min |
| Elongation | 16% min |
| Hardness | 160–210 HB |
Physical & Thermal Properties
| Property | Value |
|---|---|
| Density | 7.85 g/cm³ |
| Melting Point | 1420–1465 °C |
| Thermal Conductivity | 50 W/m·K |
| Thermal Expansion | 11.1 × 10⁻⁶ /°C |
| Elastic Modulus | 210 GPa |
| Specific Heat | 460 J/kg·K |
| Electrical Resistivity | 0.170 μΩ·m |
Equivalent Grades of EN8
| Standard Body | Equivalent Grade |
|---|---|
| BS | 080M40 (EN8) |
| AISI/SAE | 1040/1042 |
| EN/DIN | C40 / 1.0511 |
| JIS | S40C |
| IS | C40 |
Spectacle Blind Flange – Product Details
Applicable Standards: ASME B16.48, MSS SP-44
Manufacturing Process: Cut from plate, plasma or laser profiled; both discs machined to raised-face finish; handle welded.
Heat Treatment: Normalise 830–860 °C; Harden 820–850 °C, quench in oil/water; Temper 550–660 °C.
EN8 Spectacle Blind Flange – Manufacturing Process
Spectacle Blind Flange is produced using a controlled sequence of operations to achieve the dimensional and mechanical requirements of BS 970 080M40 (EN8).
1050–1200 °C
Normalise / Q&T
Face & bore
Per ASME B16.5
EN8 Spectacle Blind Flange – Sizes & Dimensions
Size range: Bars Ø 6–250 mm; flats, hexes, plates. The following dimensional data covers standard sizes. Non-standard sizes available on request.
| NPS | Flange Rating | Blind OD (mm) | Spacer OD (mm) | Blind thickness |
|---|---|---|---|---|
| 1" | 150#–600# | 125 | 69 | 14 mm |
| 2" | 150#–600# | 165 | 92 | 18 mm |
| 4" | 150#–600# | 254 | 145 | 28 mm |
| 6" | 150#–600# | 318 | 199 | 35 mm |
| 8" | 150#–300# | 381 | 254 | 42 mm |
| 12" | 150#–300# | 520 | 373 | 56 mm |
Types of EN8 Spectacle Blind Flange
- 150# Spectacle Blind
- 300# Spectacle Blind
- 600# Spectacle Blind
- Line blind (pancake blind)
Applications of EN8 Spectacle Blind Flange
Industries We Serve
Ready to order EN8 Spectacle Blind Flange?
Stock available in Mumbai. Same-day quotation. Export documentation included.
Email Quote Call NowEN8 – Grade Specification
| Standard | Category | Tensile Strength | Yield Strength | Elongation |
|---|---|---|---|---|
| BS 970 080M40 (EN8) ✓ | Medium Carbon Steel | 550–700 MPa (N) | 290 MPa min | 16% min |
| BS (080M40 (EN8)) | Equivalent | See equivalent grades table above | ||
| AISI/SAE (1040/1042) | Equivalent | See equivalent grades table above | ||
| EN/DIN (C40 / 1.0511) | Equivalent | See equivalent grades table above | ||
| JIS (S40C) | Equivalent | See equivalent grades table above | ||
| IS (C40) | Equivalent | See equivalent grades table above | ||
* All values are minimum guaranteed per BS 970 080M40 (EN8). Actual mill certificates may show higher values.
Why Buy EN8 Spectacle Blind Flange from BB Infras?
| Ready Stock | Large inventory of EN8 Spectacle Blind 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 EN8 Spectacle Blind 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 EN8 Spectacle Blind 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
Spectacle Blind Flange Marking & Identification
Every EN8 Spectacle Blind Flange supplied by BB Infras is marked per BS 970 080M40 (EN8) and ASME marking requirements. Standard marking sequence:
- Manufacturer name / mark
- Material specification — BS 970 080M40 (EN8)
- 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 EN8 Spectacle Blind 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 BS 970 080M40 (EN8) Table 1 |
| 2 | Tensile & Yield Strength | ASTM E8 | ≥550–700 MPa (N) / ≥290 MPa min |
| 3 | Elongation | ASTM E8 | ≥16% min |
| 4 | Hardness (HB) | ASTM E10 | Per standard max |
| 5 | Hydrostatic Test | BS 970 080M40 (EN8) / 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.
EN8 Spectacle Blind Flange Supplier in India
BB Infras supplies EN8 Spectacle Blind 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.
View all cities we supply ▾
EN8 Spectacle Blind Flange Exporter – Countries We Ship To
BB Infras exports EN8 Spectacle Blind 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 EN8 Spectacle Blind 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 EN8 Spectacle Blind Flange?
EN8 Spectacle Blind 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 EN8?
Per BS 970 080M40 (EN8): minimum tensile is 550–700 MPa (N) and minimum yield is 290 MPa min. Forging heat treatment normalises the material to achieve these values.
Do EN8 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 EN8 Spectacle Blind 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 |
|---|---|---|
| BS 970 080M40 (EN8) | ASTM / ASME | Material specification for EN8 |
| 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 |
